GB2539180A

GB2539180A - Causing transmission or responding to receipt of a search instruction

Info

Publication number: GB2539180A
Application number: GB1509376.8A
Authority: GB
Inventors: Savolainen Teemu; Rantaeskola Antti
Original assignee: Nokia Technologies Oy
Current assignee: Nokia Technologies Oy
Priority date: 2015-06-01
Filing date: 2015-06-01
Publication date: 2016-12-14
Also published as: GB201509376D0

Abstract

The described method relates to indoor positioning, and tracking the locations of people or assets within an indoor space such as a hospital, comprising: determining that an absence of communication between a first radio communication apparatus (such as locator devices 10-1 to 10-6) and a second radio communication apparatus (such as an asset 11 comprising a tag 11A) for longer than a pre-determined duration has occurred (such as when asset 11 moves to corridor 109, out of communications range of any locator device 10, reference C, figure 1); and responding to the determination by causing transmission to at least one recipient radio communication apparatus 13 of a search instruction for causing the recipient radio communication apparatus 13 which receives the search instruction to be set into a search mode (reference E). The recipient radio communication apparatus is responsive to detection of an occurrence of communication between the recipient radio communication apparatus and the second radio communication apparatus 11 (reference G) to perform at least one operation. The communication may use a short-range communication protocol such as Bluetooth Low Energy, BLE. Server 12 is configured to determine when asset 11 becomes lost, missing, misplaced, absent.

Description

Causing transmission or Responding to Receipt of a Search Instruction

Field

This specification relates generally to causing transmission of, or responding to receipt of, a search instruction.

Background

Indoor positioning systems are becoming increasingly common for tracking the locations of people or assets within indoor spaces. Generally such indoor positioning systems use ro locator devices that are at fixed positions within the space. It is therefore quite likely that, in a number of deployments, indoor positioning systems employing fixed locator devices will not provide l00% coverage of the entire space. Consequently, it may be possible for assets or people which are being tracked by the indoor positioning system to become lost.

/5 Summary

In a first aspect, this specification describes a method comprising determining that an absence of communication between a first radio communication apparatus and a second radio communication apparatus for longer than a pre-determined duration has occurred, and responding to the determination by causing transmission to at least one recipient radio communication apparatus of a search instruction for causing the recipient radio communication apparatus which receives the search instruction to be set into a search mode in which the recipient radio communication apparatus is responsive to detection of an occurrence of communication between the recipient radio communication apparatus and the second radio communication apparatus to perform at least one operation.

The method may comprise responding to the determination that communication between the first radio communication apparatus and the second radio communication apparatus has not occurred for longer than the pre-determined duration by identifying, from a plurality of available recipient communication apparatuses, a set of one or more recipient radio communication apparatuses based on a characteristic associated with the second radio communication apparatus and/or a characteristic associated with the set of one or more recipient radio communication apparatuses, the identified set including the recipient radio communication apparatus, and causing transmission of the search instruction to each of the recipient communication apparatuses in the identified set.

The search instruction may include information identifying the second radio communications apparatus. Setting the recipient radio communication apparatus into search mode may include the recipient radio communication apparatus initiating a scan for the second radio communication apparatus. The scan may be initiated on the basis of information included in the search instruction which identifies the second radio communication apparatus.

The search instruction may include information based on which the at least one operation that is to be performed by the recipient radio communication apparatus can be determined.

ro Determining that the absence of communication for longer than the pre-determined duration has occurred may comprise: noting an instant at which a most-recent communication between the first and second mobile radio communication apparatus took place; and detecting when a period of time since the noted instant exceeds the predetermined duration. The pre-determined duration may be dependent on a characteristic /5 associated with the second communication apparatus.

In a second aspect, this specification describes a method comprising responding to receipt by a recipient radio communication apparatus of a search instruction by setting the recipient radio communication apparatus into a search mode in which the recipient radio communication apparatus is responsive to detection of an occurrence of communication between the recipient radio communication apparatus and another radio communication apparatus by causing performance of at least one operation. The other radio communication apparatus may be identified in the search instruction.

Setting the recipient communication apparatus into search mode may include initiating a scan for incoming transmissions. Initiating the scan may comprise at least one of causing transmission by the recipient radio communication apparatus of data packets addressed to the another radio communication apparatus, and causing the recipient radio communication apparatus to listen for data packets received from the another radio communication apparatus.

The method of the second aspect may further comprise determining the at least one operation based on information included in the received search instruction.

The at least one operation may include notifying the apparatus from which the search instruction was received that the communication between the recipient radio communication apparatus and the another radio communication apparatus has occurred.

The communication between the recipient radio communication apparatus and another radio communication apparatus may be performed using a first wireless communication protocol and notifying the apparatus from which the search instruction was received may be performed using a second, different wireless communication protocol.

The at least one operation may include providing an alert for notifying the user of the recipient radio communication apparatus.

Setting the recipient communication apparatus into search mode may include activating at ro least one radio component of the recipient radio communication apparatus.

The method of the second aspect may further comprise, subsequent to causing performance of the at least one operation, disabling at least one radio component of the recipient radio communication apparatus.

In a third aspect, this specification describes apparatus configured to perform a method as described with reference to either of the first and second aspects.

In a fourth aspect, this specification describes computer-readable instructions, which 20 when executed by computing apparatus cause the computing apparatus to perform a method as described with reference to either of the first and second aspects.

In a fifth aspect, this specification describes apparatus comprising at least one processor and at least one memory having computer readable instructions stored thereon which, when executed by the at least one processor, cause the apparatus: to determine that an absence of communication between a first radio communication apparatus and a second radio communication apparatus for longer than a pre-determined duration has occurred; and to respond to the determination by causing transmission to at least one recipient radio communication apparatus of a search instruction for causing the recipient radio communication apparatus which receives the search instruction to be set into a search mode in which the recipient radio communication apparatus is responsive to detection of an occurrence of communication between the recipient radio communication apparatus and the second radio communication apparatus to perform at least one operation.

The computer readable code, when executed by the at least one processor, may cause the apparatus to respond to the determination that communication between the first radio communication apparatus and the second radio communication apparatus has not occurred for longer than the pre-determined duration by identifying, from a plurality of available recipient communication apparatuses, a set of one or more recipient radio communication apparatuses based on a characteristic associated with the second radio communication apparatus and/or a characteristic associated with the set of one or more recipient radio communication apparatuses, the identified set including the recipient radio communication apparatus, and causing transmission of the search instruction to each of the recipient communication apparatuses in the identified set.

The search instruction may include information identifying the second radio ro communications apparatus. Setting the recipient radio communication apparatus into search mode may include the recipient radio communication apparatus initiating a scan for the second radio communication apparatus. The scan may be initiated on the basis of information included in the search instruction which identifies the second radio communication apparatus.

The computer readable code, when executed by the at least one processor, may cause the apparatus to note an instant at which a most-recent communication between the first and second mobile radio communication apparatus took place, and to detect when a period of time since the noted instant exceeds the pre-determined duration thereby to determine that the absence of communication for longer than the pre-determined duration has occurred. The pre-determined duration may be dependent on a characteristic associated with the second communication apparatus.

In a sixth aspect, this specification describes apparatus comprising at least one processor and at least one memory having computer readable instructions stored thereon which, when executed by the at least one processor, cause the apparatus: to respond to receipt by a recipient radio communication apparatus of a search instruction by setting the recipient radio communication apparatus into a search mode in which the recipient radio communication apparatus is responsive to detection of an occurrence of communication between the recipient radio communication apparatus and another radio communication apparatus by causing performance of at least one operation. The other radio communication apparatus may identified in the search instruction. -5 -

Setting the recipient communication apparatus into search mode may include initiating a scan for incoming transmissions. Initiating the scan may comprise at least one of: causing transmission by the recipient radio communication apparatus of data packets addressed to the another radio communication apparatus; and causing the recipient radio communication apparatus to listen for data packets received from the another radio communication apparatus.

The computer readable code, when executed by the at least one processor, may cause the apparatus of the sixth aspect to determine the at least one operation based on information ro included in the received search instruction.

ts The communication between the recipient radio communication apparatus and the another radio communication apparatus may be performed using a first wireless communication protocol and the notifying the apparatus from which the search instruction was received may be performed using a second, different wireless communication protocol.

Setting the recipient communication apparatus into search mode may include activating at 25 least one radio component of the recipient radio communication apparatus.

The computer readable code, when executed by the at least one processor, may cause the apparatus, subsequent to causing performance of the at least one operation, to disable at least one radio component of the recipient radio communication apparatus.

In a seventh aspect, this specification describes a non-transitory computer-readable memory medium having computer readable code stored thereon, which when executed by computing apparatus, causes the computing apparatus to determine that an absence of communication between a first radio communication apparatus and a second radio communication apparatus for longer than a pre-determined duration has occurred, and to respond to the determination by causing transmission to at least one recipient radio communication apparatus of a search instruction for causing the recipient radio communication apparatus which receives the search instruction to be set into a search mode in which the recipient radio communication apparatus is responsive to detection of an occurrence of communication between the recipient radio communication apparatus and the second radio communication apparatus to perform at least one operation. The computer readable code may, when executed by the computing apparatus, cause the computing apparatus to perform any one or more of the operations described with reference to the method of the first aspect.

In an eighth aspect, this specification describes a non-transitory computer-readable ro memory medium having computer readable code stored thereon which, when executed by computing apparatus, causes the computing apparatus to respond to receipt by a recipient radio communication apparatus of a search instruction by setting the recipient radio communication apparatus into a search mode in which the recipient radio communication apparatus is responsive to detection of an occurrence of communication between the f5 recipient radio communication apparatus and another radio communication apparatus by causing performance of at least one operation. The computer readable code may, when executed by the computing apparatus, cause the computing apparatus to perform any one or more of the operations described with reference to the method of the second aspect.

In a ninth aspect, this specification apparatus comprising means for determining that an absence of communication between a first radio communication apparatus and a second radio communication apparatus for longer than a pre-determined duration has occurred and means for responding to the determination by causing transmission to at least one recipient radio communication apparatus of a search instruction for causing the recipient radio communication apparatus which receives the search instruction to be set into a search mode in which the recipient radio communication apparatus is responsive to detection of an occurrence of communication between the recipient radio communication apparatus and the second radio communication apparatus to perform at least one operation. The apparatus may further include means for causing performance any one or more of the operations described with reference to the method of the first aspect.

In a tenth aspect this specification describes apparatus comprising means for responding to receipt by a recipient radio communication apparatus of a search instruction by setting the recipient radio communication apparatus into a search mode in which the recipient radio communication apparatus is responsive to detection of an occurrence of communication between the recipient radio communication apparatus and another radio communication apparatus by causing performance of at least one operation. The apparatus may further include means for causing performance any one or more of the operations described with reference to the method of the second aspect.

Brief Description of the Figures

For a more complete understanding of the methods, apparatuses and computer-readable instructions described herein, reference is now made to the following descriptions taken in connection with the accompanying drawings in which: Figure 1 is a simplified schematic illustrating a facility in which an indoor positioning /0 system is deployed; Figure 2A is a flow chart illustrating operations which may be performed, or caused to be performed, by the server apparatus of Figure 1; Figure 2B is a flow chart illustrating operations which may be performed, or caused to be performed, by the recipient apparatus of Figure 1; and Figures 3A, 3B and 3C are highly simplified schematics of example configurations of the various apparatuses that may make up a system such as that illustrated in Figure 1.

Detailed Description

In the description and drawings, like reference numerals may refer to like elements 20 throughout.

Figure l is a simplified schematic illustrating a facility in which an indoor positioning system is deployed. Figure 1 also shows examples of operations which may be performed within the system in relation to finding lost people or assets (from here, simply referred to as "assets"). An example of an order in which the various operations might be performed is indicated in Figure 1 using references A to H. The exchange of electronic signals (either wired or wireless) is indicated by solid arrows and movements of apparatuses, devices or assets are indicated by broken arrows.

The facility, in this example, is made up of a number of separate spaces 101-109. Most of these spaces 1o1-109 include a communication apparatus 10-1 to 10-6 configured to enable tracking of assets within that space (hereafter referred to as "locator devices". However, other spaces in the facility 107-109 do not have a locator device provided therein. Such spaces may include, for instance, corridors 107, 108 in which it may not generally be required to track assets or people or outdoor spaces in which locator devices are not generally deployed.

In the example of Figure 1, first to sixth spaces 101-106 are each provided with a locator device 10-1 to 10-6 for enabling tracking of assets 11 within that space. When the asset 11 is within any of these spaces, the respective locator device is operable to communicate with a radio communications apparatus HA associated with the asset 11. Based on the communication, it may be possible for the locator device 10-1 to 10-6, or a further computing apparatus 12 in communication with the locator device 10-1 to 10-6, to determine a location of the radio communication apparatus nA associated with the asset 11, or at least to determine that the radio communication apparatus HA is present within the space.

For simplicity, radio communication apparatuses nA associated with an asset 11 will hereafter be referred to as a tag nA. However, it will be appreciated that radio communication apparatus nA associated with an asset 11 which may be located using the locator devices are not limited to "tags". For instance, the functionality provided by a tag /5 may be provided by any suitable type of radio communication apparatus such as, but certainly not limited to, a smartphone. In some specific examples, tags HA are configured periodically to emit a data packet (e.g. a Bluetooth packet), which is receivable and decipherable by the locator devices 10-1 to 10-6. The data packet includes an identifier of the tag which transmits it.

Each locator device 10-1 to 10-6 is, in this example, configured to communicate with the tag HA associated with an asset it, and with server apparatus 12. Together the locator devices 10-1 to 10-6 and the server apparatus 12 may be referred to as a positioning system. In some examples, the locator devices 10-1 to 10-6 may be multi-antenna array devices which are operable to estimate a bearing from which transmissions are received from the tag nA or along which transmissions are sent to the tag nA. In such examples, the data packets passed from the tag HA to the locator device 10-1 to 10-6 (or vice versa) may have a specific format which enables determination/estimation of the bearing using the multi-antenna locator device 10-1 to 10-6. This specific format is known in the art and so is not discussed further in this specification. Alternatively, one or more of the locator devices 10-1 to 10-6 may simply be a single antenna device that is operable to detect the presence of a tag nA within communication range. In these examples, the format of the packet may not be required to be quite so specific as long as they can be received by the locator devices 10-1 to 10-6 and the identity of the transmitting tag nA determined.

In this simplified example, the range within which a locator device 10-1 to to-6 is able to detect the presence of a tag nA is equivalent to the size of the space within which the locator device is provided. It will of course, however, be appreciated that in real world scenarios this may not always be the case.

In the example of Figure 1, an asset n having a tag nA is located within the second space 102. As such, wireless communication (reference A) between the tag nA and the locator device 10-2 is taking place. The occurrence of this communication enables the locator device 10-2 (or the server apparatus 12) to detect the presence and/or location of the tag HA within the space 102. In response to the occurrence of the communication between the locator device 10-2 and the tag HA, a signal is passed (reference B), either wirelessly or ro via a wired connection, to the server apparatus 12. This signal indicates that an instance of communication between the tag nA and the locator device 10-2 has occurred.

In this particular example, after communicating with the locator device 10-2, the tag nA, carried by the asset 11, leaves the second space 102 (reference C) and moves to the ninth /5 space 109 via the corridor 108 where it remains.

The server apparatus 12, in response to receiving the signal from the locator device 10-2 makes a note of the instant at which the communication between the locator device 10-2 and the tag HA occurred. However, following the movement of the tag HA out of the range of any of the locator devices 10-1 to 10-6 and into a space 109 which is not covered by any of the locator devices 10-1 to 10-6 of the positioning system, no further signals related to the tag nA are received at the server apparatus 12.

The server apparatus 12 is configured to detect when communication between a particular tag nA and any of the locator devices 10-1 to 10-6 within the positioning system has not occurred for longer than a predetermined duration (reference D). Put another way, the server apparatus 12 is configured to determine when the asset 11 associated with the tag HA becomes lost. For instance, the server apparatus 12 may determine that no signals relating to the tag nA have been received from any of the locator devices 10-1 to 10-6 within a predetermined duration since the noted instant of communication between the tag and the second locator device 10-2.

This detection or determination may be performed in any suitable manner. For instance, a timer having the predetermined duration may be started in response to receipt by the server apparatus 12 of a signal from a locator device 10-2 indicating occurrence of communication with a tag nA. If new signals relating to the same tag 11A are received at the server apparatus 12 from any of the locator devices 10-2 to 10-6 in the same system, the server apparatus 12 may respond by restarting the timer but, if the timer expires, the server apparatus 12 may determine that the tag nA and associated asset 11 have become lost. Alternatively, the server apparatus 12 may be configured to respond to the received signal by noting a future instant or time, which is the time of the noted instant plus the predetermined duration, by which a signal relating to communication between a locator device 10-1 to to-6 and the tag nA must have been received. If no such signal is received by this future time, the server apparatus 12 may determine that the asset 11 associated with the tag nA has become lost.

ro In response to determining that the asset 11 associated with the tag nA has become lost, the server apparatus 12 may be configured to identify or determine a search strategy for locating the asset 11. Identifying a search strategy may include identifying at least one recipient radio communication apparatus 13 of a set of one or more possible recipient apparatuses to which to transmit a search instruction. For simplicity, hereafter recipient /5 radio communication apparatuses will be referred to as recipient devices.

Each of the set of possible recipient devices 13 may have one or more associated characteristics, which may be known by the server apparatus 12. These characteristics may include, for instance, a level, category and/or location information of the recipient device 13 or its user or owner. In a hospital scenario, for instance, various different personnel may carry recipient devices 13. These personnel may include doctors, nurses, janitors, maintenance workers, security personnel etc. As such, each recipient device 13 may be assigned a level dependent on the job title of its user. As such, when identifying new search strategy, the server apparatus 12 may determine that the search instruction should only be sent out to recipient devices 13 used by personnel of a particular level.

Similarly, the recipient devices may be determined or identified based on location information associated with the device 13. This location information may include a current location of the recipient device 13, for instance obtained using the positioning system. The current location information may be of various different resolutions. For instance, it may simply indicate whether the recipient device is currently within the facility, it may indicate a current floor of the facility on which the device 13 is present and/or it may indicate a particular space (e.g. room or department) within the facility. In other examples, non-current location information may be used, e.g. which indicates a floor, room or department in which the device normally resides. When the recipient devices are identified based on location information, the server apparatus 12 may, for instance, only identify those recipient devices for which the location information indicates that they are within a reasonable range of a last known location and/or a usual location of the tag nA.

The search strategy may be formulated based on a characteristic associated with the asset 11 with which the tag nA is associated. Such characteristics may include priority or importance level, location information and physical specification information. The location information may specify the last known location or may specify a usual location for the asset. The physical specification information may for instance indicate a weight or size of the asset.

Once again considering the hospital scenario, it may be desirable to track a number of different types of asset and a priority or importance level may be associated with each type. For instance, assets such as patients may be categorised as high priority assets whereas certain relatively inexpensive hospital equipment may be categorised as low /5 priority assets. The server apparatus 12 may, therefore, be configured to identify or determine a different search strategy depending on the characteristic of the asset (e.g., if the asset is high priority or low priority). If the asset is high priority, for instance a patient, the server apparatus 12 may determine that every recipient device 13 in the set of possible recipient devices should receive the search instruction so as to relocate the lost high priority asset as quickly as possible. Conversely, if the asset is of low priority, such as a relatively inexpensive piece of equipment, the server apparatus 12 may determine that only a subset of the possible recipient devices, for instance the recipient devices belonging only to janitors and maintenance workers, should receive the search instruction.

The physical specification characteristic of the asset may be used to identify the recipient devices. For instance, if the physical specification characteristic indicates that the device is very large or heavy, only those recipient devices on the same floor as last known location of the asset will be indentified (e.g. because it may be unlikely for very large or heavy assets to be moved between floors).

Identifying the search strategy may include preparing the search instruction based on the characteristic associated with the identified recipient device 13 and/or the lost asset 11. For instance, the search instruction may include instructions for performance of a different set of one or more operations depending on the characteristic of the asset 11 and/or the recipient device 13 to which the instruction is being sent. This is discussed in further detail below.

After formulating the search strategy, the server apparatus 13 causes a search instruction to be transmitted to each of the identified recipient devices (reference E). In the example of Figure 1, just a single recipient device 13 is identified. The recipient devices 13 are configured to respond to receipt of the search instruction by performing one or more operations. The one or more operations may be predefined such that the recipient device 13 is configured to respond to receipt of a search instruction in a predefined manner. Alternatively, the operations performed may be determined based on information provided within the search instruction. This is discussed in more detail below with reference to Figures 2A and 2B. I0

In some examples, the recipient device 13 may be configured to respond to receipt of the search instruction by alerting the user of the device 13 that a particular asset is missing. This alert may encourage the user to move away from their current location (reference F), for instance to areas of no, or poor, coverage by the positioning system, in order to locate /5 the lost asset 11. In the example of Figure 1, the user of the recipient device 13 happens to move from the first space 101 to the ninth space 109, in which the lost asset 11 is now located. Whether or not an alert is provided in response to receipt of the search instruction may depend on the characteristic associated with the recipient device 13 and/or the lost asset. For instance, where an asset is high priority (e.g. a patient), all recipient devices 13, regardless of their category or level, may respond to the search instruction by alerting the user to the lost asset. Where the asset is of medium priority, only the recipient devices 13 having a characteristic indicating a user of low level may respond by alerting the user, while recipient devices 13 having a characteristic indicating a user of high level may respond to receipt of the search instruction in other ways (such as those discussed below) but may not alert the user. Finally, where the asset is of low priority, none of the identified the recipient devices 13 may respond by alerting the user, regardless of the associated characteristic. When the recipient device 13 does not respond by providing an alert, other operations may be performed by the recipient device 13 in order to locate the lost asset, but these may be performed by the device 13 with the user going about their normal business, oblivious to the asset being lost.

The recipient device 13 may be configured to respond to receipt of the search instruction by being set into a search mode in which it is configured to respond to an occurrence of communication between the tag nA and the recipient device 13 (reference G) by performing one or more operations. Setting the device 13 into search mode may include initiating a scan for the tag nA associated with the lost asset 11. Setting the device 13 into search mode may also include activating one or more radio components (e.g. the transceiver 135) of the recipient device 13. The scanning may include polling the tag nA using an identifier associated with the tag 11A (a tag identifier) and/or listening for transmissions from a tag nA associated with the tag identifier. The one or more operations performed in response to occurrence of communication between the tag nA and the recipient device 13 may include, for instance, by providing an alert to the user of the recipient device and/or causing transmission of a notification (reference H) back to the server apparatus 12. The notification transmitted to the server apparatus 12 may indicate that the lost asset has been found. The recipient device 13 may additionally respond to the incoming search instruction by alerting the user and/or presenting ro information regarding the lost asset to the user. Although not illustrated in Figure 1, the server apparatus 12 may respond to the notification by transmitting messages to the identified one or more recipient devices 13 in order to rescind the search instruction.

The communication between the tags nA and the locator devices 10-1 to 10-6 may be r5 performed using any suitable protocol. Bluetooth Low Energy (BLE), due to its relatively low energy consumption may be particularly well suited, although other protocols may alternatively be used.

The communication between the tags 11A and the recipient devices 13 may be performed using the same protocol as that used for communication between the tags 11A and the locator devices 10-1 to 10-6 (e.g. where the tag is only capable of communicating using a single protocol), although other protocols may be used. Once again, BLE may be particularly well-suited.

Communication between the server apparatus 12 and the recipient devices 13 may be performed using any suitable protocol or combination or protocols. In some examples, the server apparatus 12 may cause the locator devices to-1 to to-6 to transmit the search instructions. In other examples, the server apparatus 12 may cause transmission of the search instruction using WiFi (e.g. via a wireless router) or using a cellular transmission protocol, for instance as an SMS. In yet other examples, the recipient device 13 maybe configured to have an active connection with the server apparatus 12 over a network such as the Internet. The server apparatus 12 may cause transmission of the search instruction over this connection. For instance, each of the recipient devices 13 may be registered as a client to the search service provided by server apparatus 12. This active connection may be over the Internet using any suitable protocol, such as H rrp, HTITS, COAP, MQTT, WebSocket, TLS, TCP, UDP, IP, IPv6 etc. As will be understood from the above discussion, the positioning system described with reference to Figure 1 provides a neat and flexible solution for relocating lost assets. Moreover, the formulation of a suitable search strategy on the basis of characteristics associated with the lost asset and/or recipient devices enables a good balance to be reached with respect to finding the missing asset in a timely fashion and efficiently utilising resources of the system (such as power, processing and bandwidth resources). In particular, searching for tags consumes processing and battery power of the recipient devices and sending search instructions requires signalling, which uses battery and network bandwidth of the recipient devices. Thus, although an asset may be found faster ro if a search instruction is sent to all recipients, this may be unnecessarily draining on the resources of the system. As such, the search strategy is formulated in order to find a good trade-off between the need to find an asset and the need to conserve the resources of the system.

/5 Examples of various operations which may be performed by the server apparatus 12 and the recipient device(s) 13 will now be described in further detail with reference to the flow charts of Figures 2A and 2B. For illustrative purposes, an example of a flow of communications between the server apparatus 12 and the recipient devices 13 is shown schematically on Figures 2A and 2B.

Figure 2A is a flow chart illustrating operations which may be performed, or caused to be performed, by the server apparatus 12.

In operation S2A.1, the server apparatus 12 receives an indication of an occurrence of communication between a locator device e.g. 10-2 and a tag 11A associated with a particular asset 11. Depending on the configuration of the positioning system, this indication may be received via wired or wireless communication from the location device 10-2.

In operation S2A.2 the server apparatus 12 responds to receipt of this indication by noting an instant (or time) at which the communication with the tag nA occurred. In some examples, noting the instant at which the communication occurred may include starting a timer. Alternatively, it may include determining a time in the future at which, if particular requirements are met, further action will be taken. The timer may be set to expire after the predetermined duration. Similarly, the time in the future may be determined by summing the time at which the communication with the tag nA occurred with the predetermined duration.

The length of the predetermined duration may be determined based on a characteristic associated with the asset ir with which the tag irA is associated. For instance it may be acceptable for an asset of low priority (e.g. a low cost piece of equipment) to be out of communication for longer than a high priority asset (e.g. a patient). Consequently the server apparatus 12 may determine a longer predetermined duration for assets having a first characteristic (e.g. low priority) than for assets having a second characteristic (e.g. high priority). The characteristics associated with various tags may be stored in a look-up table within memory of the server apparatus 12.

Next, in operation S2A.3 the server apparatus 12 determines based on signals received from the locator devices 10-1 to 10-6 in the positioning system whether another communication with the tag 11 has occurred. If another communication with the tag riA has occurred (i.e. a positive determination), the server apparatus 13 returns to perform operation S2A.2 and notes the instant at which the second communication occurred.

If, however, no new communication with the tag riA is detected, the server apparatus 12 causes performance of operation 82A.4. In operation S2A.4, the server apparatus 12 determines whether an absence of communication between the tag riA and the locator devices 10-1 to to-6 of the positioning system that is longer than the predetermined duration has occurred. As discussed above this may be detected on the basis of expiry of a timer or a determination that a current time matches the previously calculated future time. The exact method by which this determination is made may not be important as long as the server apparatus 12 is able to detect when a particular tag nA has been out of communication for longer than a predetermined length of time.

If the duration of the absence of communication with the tag 11A does not exceed the predetermined duration, the server apparatus 12 continues to listen for signals indicating communication with the tag irA until either such an indication is received or the absence of communication exceeds the predetermined duration.

In response to determining that the duration has been exceeded, the server apparatus 12, in operation S2A.5, identifies a set of one or more recipient devices 13 from a plurality of available recipient devices to which a search instruction should be sent. The identification of the recipients may be based on one or more characteristic associated with the tag riA and/or one or more characteristic associated with the recipient device 13.

The server apparatus 12 may be configured to determine the characteristic associated with the tag based on a tag identifier received from the location device 10-2, for instance in operation S2A.1. As mentioned above, the server apparatus 12 may store a look-up table which specifies a characteristic of each of the tags nA within the system. Alternatively, information identifying the characteristic of a particular tag nA may be received from the locator device 10-2 which may in turn have received the information from the tag nA, for instance during the communication between the two entities. Characteristics associated with the tag nA may include an indication of a priority level associated with the asset n carrying the tag nA. There may be any different number of suitable priority levels. The ro priority levels of the assets may be decided by operators or administrators of the system and may be determined taking a number of parameters (e.g. price, owner etc) into account. Other characteristic associated with the tag and on which the search strategy may be formulated include: price/value of the asset, owner/identity of the asset, a number of assets of same type which are currently missing (for instance, a single blood pressure /5 meter being missing may not be particularly important, but if many are lost then finding of those becomes higher priority), a likelihood of the lost asset being needed in future, an explicit user input (for instance, an administrator explicitly telling the system that a specific asset needs to be located, e.g. if needed for maintenance or if theft is suspected). It will thus be appreciated that some characteristics are static (e.g. value/price) while others may be dynamic (e.g. number of lost assets of same type).

Characteristics associated with all possible recipient devices 13 may also be stored at the server apparatus 12. The characteristics of the recipient devices 13 may for instance denote an importance level (e.g. based on job title) of the users of the recipient devices 13.

For instance, some users may be considered of high importance, others of medium importance and others of low importance. For instance, in a hospital environment, the characteristic of recipient devices 13 carried by doctors and nurses may indicate high importance, recipient devices 13 carried by hospital porters may have an associated characteristic indicating medium importance level, and recipient devices 13 carried by janitors and maintenance men may have an associated characteristic indicating low importance level.

In such a scenario, the server apparatus 12 may determine that, if a missing tag nA is of a particular priority, only those devices having certain levels of importance should be sent a search instruction. For instance, for tags itA of the highest priority, the server apparatus may determine that all possible recipient devices 13 should be sent a search instruction. In contrast, if the tag nA has a characteristic indicating it to be of the lowest priority the server 12 may determine that only those recipient devices 13 with users of the lowest level of importance should be sent the search instruction.

As mentioned previously, the characteristics of the recipient devices 13 include location information. The location information may, for instance, indicate a current (or most-recent) location or an expected/usual location of the recipient device 13. The location information may include varying degrees of resolution (e.g. presence in the facility, current floor or department in the facility, and current space within the facility). In such examples, the server apparatus 12 may determine that for tags of e.g. high priority all ro devices present in the facility should be sent the instruction, whereas for tags e.g. of low priority, only devices on a particular floor should be sent the instruction.

As will be appreciated, the recipient devices 13 may be identified based on two or more associated characteristics, for instance location information and importance level of the /5 user.

After identifying the recipient devices 13 to which the search instruction 3o is to be sent, the server apparatus 12, in operation S2A.6 prepares one or more search instructions for transmission to the identified devices. The search instruction 3o may include information regarding the tag nA or the asset n associated with it. This information may include one or more characteristic (e.g. high/low priority) and/or other information (e.g. identity/type etc of the lost asset) and/or a tag identifier.

The search instruction 3o may, in some examples, be prepared based on the characteristic associated with the tag 11A. For instance, the search instruction 3o may be configured to cause performance of a first set of one or more operations (e.g. alert the user of the recipient device to the lost asset, set the recipient device into search mode) for a tag EA having one characteristic but may be configured to instruct performance of a different set of operations (e.g. only set the recipient device into search mode) for a tag nA having a second characteristic. In some examples, the server apparatus 12 may be configured to prepare different search instructions 3o for recipient devices 13 having different characteristics. As such, recipient devices 13 having one characteristic may be sent a search instruction 3o instructing a first set of operations to be performed, while recipient devices 13 having a different characteristic may be sent a search instruction 3o instructing performance of a different set of operations. In some examples, the same search instruction 3o may be prepared for each recipient (e.g. specifying a characteristic associated with the tag).

As an example of the above, the server apparatus 12 may be configured, if the tag nA is of low priority, to cause the recipient device 13 only to be set into search mode thereby to notify the server apparatus 12 when a communication with the tag is detected (i.e. the tag riA has been found). Whereas, if a tag is of high priority the server apparatus 12 may transmit a search instruction causing the device to be set into search mode and provision by the recipient device 13 of an alert for alerting the user that a lost asset has been found. As discussed above, the search instruction 3o may also indicate whether or not the recipient 13 should provide an alert to the user upon receipt of the instruction, thereby ro indicating that the asset is lost and that a search has been initiated. in other examples, a search instruction for causing initiation of search mode and provision of the alerts to the user may be transmitted to recipient devices 13 having an associated low importance whereas a search instruction 3o for causing only notification to the server apparatus 12 may be transmitted when the recipient device is of high importance.

Next, in operation S2A.7, the server apparatus 12 causes transmission of the one or more search instructions 3o to the identified recipient devices 13. After this the server apparatus 12 proceeds to operation S2A.8 in which it scans for incoming transmissions.

Next, following receipt of a transmission, the server apparatus proceeds to operation S2A.9. In operation S2A.9, the server apparatus determines if the incoming transmission was a notification received from one of the recipient devices 13 indicating that the missing tag nA has been located. If a negative determination is reached (i.e. the missing tag has not been relocated), the server apparatus 12 returns to operation S2A.8 and scans for further incoming signals. If, however, a positive determination is reached (i.e. a notification is received from a recipient device that the missing tag has been relocated), the server apparatus proceeds to operation S2A.io in which the search is ended. As depicted, ending the search may include the server apparatus sending messages to the identified recipient devices 13 for rescinding the previously transmitted search instruction.

Although not shown in Figure 2A, if, at any time after operation S2A.4, the server apparatus 12 receives an indication from one of the locator devices that a communication with the lost tag nA has occurred, the server apparatus 12 may proceed directly to operation S2A.10 in which the search is ended. in such a situation, the server apparatus 12 may also cause transmission of a message 32 for rescinding or cancelling the previous search instruction.

The server apparatus 12 may be further configured to determine that it has not received notification that a lost tag nA has been found within a predetermined time period. In response to this, the server apparatus 13 may be configured to transmit a message to an administrator indicating that an asset has become lost. Alternatively or additionally, the server apparatus 12 may respond by identifying a larger set of recipient devices and transmitting a search instruction to the devices in the larger set. For example, if the initial set of devices included those of a particular importance level or those located on a particular floor of the facility, the larger set may include devices of more than one importance level or located also on other floors. This increasing of the set of devices may ro be performed one or more times. If the lost asset is still not found, the server apparatus 12 may respond by causing a message to be sent to an administrator.

Figure 2B is a flow chart illustrating an example of operations which may be performed by one of the recipient devices 13.

In operation S2B.1, the recipient device 13 receives a search instruction 3o from the server apparatus 12. In response to receiving the search instruction 3o, the recipient device 13 in operation S2B.2 sets itself into a search mode, which may include enabling or activating one or more radio components of the device 13. In the search mode, the recipient device 13 is configured to respond to detection of an occurrence of communication between the recipient device 13 and a lost tag nA by causing performance of at least one operation. The at least one operation may include notifying the server apparatus 12 as to the occurrence of communication between the recipient device 13 and the lost tag nA and/or alerting the user of the recipient device. When in search mode, the recipient device 13 may perform at least one of scanning for transmissions received from the missing tag nA and transmitting signals/transmissions thereby to poll the missing tag nA. The scanning and/or polling may be specific only to the lost tag nik and so may be performed using an identifier of the tag included in the search instruction. Alternatively, the recipient device may scan for or poll any tags nA of a particular type.

In addition to setting itself into search mode, the recipient apparatus 13 may additionally respond to the search instruction 3o by alerting the user to receipt of the incoming search instruction. This alert may be of any suitable type and may include provision to the user of information regarding the tag nA or the associated asset. The presented information may be included in the search instruction and/or may be determined based on information included in the search instruction (e.g. based on an identifier indicating a characteristic associated with the tag). The recipient device may be configured to determine how to respond to the search instruction based on information included in the search instructions. For instance, if the recipient device 13 has a particular characteristic, it may determine whether or not an operation should be provided in response to receipt of the search instruction 3o based on a characteristic of the missing tag 11A which is derivable from information included in the search instruction 3o. For instance, if the recipient device 13 is of high importance it may determine that an alert of receipt of the search instruction 3o should be provided to the user if it is derivable from the instruction 30 that the missing tag tiA is of high priority but that an alert should not be provided if it is determined that the missing tag HA is of low priority.

When in the search mode, the recipient device 13 may be configured to respond to a subsequent message from the server apparatus 12 for rescinding the search instruction by disabling search mode. This is indicated in Figure 2B by operation S2B.3 in which the recipient device 13 determines whether a subsequent message 32 for rescinding the search /5 instruction has been received from the server apparatus 12. If such a message has been received, the recipient device 13 proceeds to operation 82B.7 in which the search mode is disabled. Alternatively, if such message has not been received, the recipient device scans, or continues to scan, for incoming transmissions. In examples in which search mode also includes polling for tags, operation S2B.4 may include polling for the missing tag 11A and subsequently scanning for incoming responses.

Next, in operation SB.5, it is determined if a communication from the missing tag 11A has been received. This may be determined by comparing an identifier included in the incoming transmission with an identifier included in the search instruction. If the two identifiers match, it is determined that a communication has indeed been received from the missing tag 11A.

If, in operation 82B.5, a negative determination is reached (i.e. no communication has been received from the missing tag tiA), the method returns to one of operations 82B.3 and S2B.4.

If, however, a positive determination is reached, the recipient device 13 causes at least one operation to be performed.

The recipient device may be configured to determine which operation should be performed based on information included in the search instruction. For instance, if it is derivable from the search instruction that the missing tag 11A has a particular characteristic (e.g. is of high priority), the recipient device 13 may determine that a first set of one or more operations should be performed if a transmission from the missing tag 11A is received. If the incoming search instruction 3o indicates the missing tag 1113 to have a different characteristic (e.g. that is of low priority), the recipient device 13 may determine that a second different set of one or more operations should be performed. As will be appreciated, the first and second set of operations may include operations that are present in both sets.

As described previously, the operations may include transmitting a notification 31 that the lo missing tag 11A has been located back to the server apparatus 12. The operations may also or alternatively include causing provision of an alert to a user of the recipient device 13. The transmission of the notification 31 to the server apparatus 12 may be performed using a similar protocol to that with which the search instruction 3o was received but a different protocol to that with which the incoming transmission was received from the lost tag 11A.

/5 For instance, the notification 31 may be transmitted over Wi-Fi or cellular, whereas the transmission from the missing tag nA may have been received using BLE.

As mentioned above, in some examples the operations that should be performed by the recipient device in in the event of communication between a missing tag nA and the device 13 may be indicated within the search instruction.

Finally, after performing the at least one operation, the recipient device 13 proceeds to operation S2B.7 in which it disables the search mode. The recipient device 13 may also disable the radio components if they are no longer needed for other purposes.

Whether or not an alert is provided to the user of the recipient device 13 (either on receiving the search instruction or on locating a lost asset) may be dependent on characteristics of the recipient device 13 and/or the asset 11/tag 11A. For instance, the characteristics may indicate that the user of the recipient device 13 is not authorised to interact with the lost asset a In such cases, the recipient device 13 may enter itself into search mode in order to locate the missing asset but the user may be unaware of this. When the asset 11 is found, a notification for causing an alert that the asset n has been found may be caused to be sent to a different recipient device 13, the user of which is allowed interact with the asset. Transmission of this notification may be caused by the server apparatus 12 in response to receiving the notification from the device 13 that located the asset (e.g. the one having the unauthorised user) or may be sent directly from the device that located the asset.

Although not shown in Figure 2B, in some examples, the search mode may be disabled if the missing tag is not located within a particular period of time. Put another way, the recipient device 13 may be configured to disable search mode after it has been unsuccessfully searching for a particular tag for in excess of an allowable duration.

Although not illustrated in any of the figures, it will be appreciated that a single recipient device 13 may receive search instructions relating to various different missing tags and so may search for the various different missing tags concurrently. In such a case, search ro mode may only be disabled when all of the lost tags have been found. In other examples, search mode may time out if all lost tags have not been found within the predetermined duration.

As will be appreciated, the methods illustrated in Figures 2A and 2B are examples only.

/5 As such, various operations may be omitted and the order in which certain operations are performed may be different to that shown in the figures. For instance, in some examples, identification of the recipient devices in operation S2A.5 and preparation of the search instructions may be performed concurrently or in a reverse order to that shown in Figure 2A. Similarly, the determination of 52B.3 as to whether a communication 32 for rescinding the search instruction has been received from the server apparatus 12 may not actually be determined at that point in the method. Instead, the determination may not be actively made but instead the recipient device 13 may be generally responsive at any time to receipt of the communication 32 for rescinding the search instruction to proceed to operation S2B.7 thereby disabling the search mode.

Figures 3A, 3B and 3C are highly simplified schematics of example configurations of the various entities that may make up a system such as that illustrated in Figure 1.

Specifically, Figure 3A illustrates an example configuration of the positioning system 300, including the server apparatus 12 and plural location devices 10-2, 10-3. Figure 3B illustrates an example configuration of one of the recipient devices 13, and Figure 3C illustrates an example configuration of a tag nA.

Each of the apparatuses 12, 10-2, 10-3, 11A, 13 includes a controller 120, 10-20, 10-30, 110, 130. Each of the controllers 120, 10-20, 10-30, 110, 130 includes processing circuitry 121, 10-21, 10-31, 111, 131 coupled with memory 122, 10-22, 10-32, 112, 132. The memory 122, 10-22, 10-32, 112, 132 has stored thereon computer readable instructions 122A, 10-22A, lo-32A, 112A, 132A, which when executed by the processing circuitry 121, 10-21, 10-31, 111, 131 causes the apparatus 12, 10-2, 10-3,11A, 13 or entity in which the controller 120, 1020, 10-30, 110, 130 is provided to perform the various functions and operations described above with reference to Figures 1, 2A and 2B. The controllers 120, 10-20, 10-30, 110, 130 are also configured by way of the computer readable instructions 122A, lo-22A, 10-32A, ii2A, 132A to control the other components in their entity.

The memory 122 of the server apparatus 12 may additionally include one or more lookup tables including information relating to characteristics of one or more tags HA and one or more recipient devices 13. The memory 132 of the recipient device 13 may additionally ro include one or more lookup tables including information relating to characteristics of one or more tags 11A and/or operations that it may perform in response to receipt of the search instruction.

The server apparatus 12 may additionally include a transceiver 123 and antenna 124 for rs transmitting and/or receiving signals, such as search instructions 30 and messages for rescinding search instructions 32, to/from the recipient devices 13. In other examples, the transceiver 123 and antenna 124 may be provided in a separate entity that is communicatively coupled with the server apparatus 12. The transceiver 123 may be configured to operate using any suitable protocol including, but not limited to BLE, WiFi and cellular protocols. As mentioned previously, the server apparatus 12 and the recipient devices 13 may be configured to communicate of the Internet using any suitable protocol, such as HTTP, HTTPS, COAP, MATT, WebSocket, TLS, TCP, UDP, IP, TPv6 etc. The recipient devices 13 may include a transceiver 133 which is operable under the control of the controller 130 to receive and transmit messages from and to the server apparatus 12 via an antenna 134. The recipient device 13 may additionally include another transceiver 135 and antenna 136 configured to operate using a different transmission protocol to the first transceiver 133 via which transmissions may be received from tags irA. In other examples, the recipient device 13 is configured to communicate with the server 12 and the tags 11A using the same protocol via a single transceiver and antenna or using different protocols but using a single transceiver and antenna.

The recipient device 13 may also include an output interface 137 for providing alerts to the user of the device.

The tag 11A additionally includes a transmitter 113 for transmitting signals which indicate its presence to the location devices 10-2, 10-3 and the recipient devices 13. In some cases, the tag nA may include a transceiver instead of a simple transmitter thereby to allow transmisson and reception of signals. This may be the case, for instance, where the tag functionality is provided by a more complex device such as a smartphone.

The locator devices 10-2, 10-3 may be of any suitable construction as long as they are configured to determine the presence in the vicinity of a transmitting device, such a tag nA. All of the locator devices 10-1 to 10-6 in the positioning system 30o may have the same construction or alternatively some may have different constructions. In the example of Figure 3A, one of the location devices 10-2 is a multi-antenna device and so comprises /0 plural antennas lo-25A, lo-25B, lo-25C and a switch 10-24 for switching between the antennas 10-25A, 10-25B, 10-25C thereby to enable determination of a bearing towards the tag nA. The other location device 10-3 in Figure 3A includes only a single antenna 1034 and so may be configured only to detect the presence of a transmitting device such as the tag nA and not also its direction. Both types of locator devices 10-2, 10-3 include a /5 receiver (or a transceiver) 10-23, 10-33. The locator devices may pass signals to the server apparatus 12 in any suitable way. The locator devices may be configured to operate using any suitable transmission protocol, such as but not limited to BLE and WiFi.

As will of course be appreciated, any of the described apparatuses 12, 10-2, 10-3, nA, 13 or entities may comprise only the indicated components or one or more additional components. The one or more additional components may depend on the nature of the device. For instance, where the recipient device 13 is a smart phone, the device will include various other components such as a display, a touch interface, etc. In examples in which the tag nA is just a simple transmitting device, the construction may be very similar to that shown in Figure 3C. However, in some examples the functionality of the tag may be provided by a more complex device or apparatus such as a smart phone in which case additional components will be included.

Some further details of components and features of the above-described apparatuses 12, 10-2, 10-3, 11A, 13 and alternatives for them will now be described.

The processing circuitry 121, 10-21, 10-31, 111, 131 of any of the apparatuses 12, 10-2, 10-3, 11A, 13 of Figures 1 and 3A to 3C may be of any suitable composition and may include one or more processors 121A, lo-21A, inA, 131A of any suitable type or suitable combination of types. For example, the processing circuitry 121, 10-21, 10-31, 111, 131 may be a programmable processor that interprets computer program instructions and processes data. The processing circuitry 121, 10-21, 10-31, in, 131 may include plural programmable processors. Alternatively, the processing circuitry 121, 10-21, 10-31, 111, 131 may be, for example, programmable hardware with embedded firmware. The processing circuitry 121, 10-21, 10-31, 111, 131 may be termed processing means. The processing circuitry 121, 10-21, 10-31, 111, 131 may alternatively or additionally include one or more Application Specific Integrated Circuits (ASICs). In some instances, processing circuitry 121, 10-21, 10-31, 111, 131 may be referred to as computing apparatus.

The processing circuitry 121, 10-21, 10-31, 111, 131 is coupled to the respective memory (or one or more storage devices) 122, 10-22, 10-32, 112, 132 and is operable to read/write data ro to/from the memory 122, 10-22, 10-32, 112, 132. The memory 122, 10-22, 10-32, 112, 132 may comprise a single memory unit or a plurality of memory units, upon which the computer readable instructions (or code) 122A, lo-22A, lo-32A, 112A, 132A is stored. For example, the memory 122, 10-22, 10-32, 112, 132 may comprise both volatile memory and non-volatile memory. For example, the computer readable instructions 122A, 10-22A, 10- 32A, 112A, 132A may be stored in the non-volatile memory and may be executed by the processing circuitry 121, 10-21, 10-31, 111, 131 using the volatile memory for temporary storage of data or data and instructions. Examples of volatile memory include RAM, DRAM, SDRAM etc. Examples of non-volatile memory include ROM, PROM, EEPROM, flash memory, optical storage, magnetic storage, etc. The memories in general may be referred to as non-transitory computer readable memory media.

The term Memory', in addition to covering memory comprising both non-volatile memory and volatile memory, may also cover one or more volatile memories only, one or more non-volatile memories only, or one or more volatile memories and one or more non-volatile memories.

The computer readable instructions 122A, 10-22A, 10-32A, 112A, 132A may be preprogrammed into the apparatuses 12, 10-2, 10-3, 11A, 13. Alternatively, the computer readable instructions 122A, 10-22A, 10-32A, 112A, 132A may arrive at the apparatus 12, 10-2, 10-3, 11A, 13 via an electromagnetic carrier signal or may be copied from a physical entity 210 (see Figure 3B) such as a computer program product, a memory device or a record medium such as a CD-ROM or DVD. The computer readable instructions 122A, 1022A, lo-32A, 112A, 132A may provide the logic and routines that enables the devices/apparatuses 12, 10-2, 10-3, 11A, 13 to perform the functionality described above.

The combination of computer-readable instructions stored on memory (of any of the types described above) may be referred to as a computer program product.

Where applicable, the BLE-capability of the apparatuses 12, 10-2, 10-3, 11A, 13 may be provided by a single integrated circuit. It may alternatively be provided by a set of integrated circuits (i.e. a chipset). The BLE-capability may alternatively be a hardwired, application-specific integrated circuit (ASIC).

Although the specific embodiments have been described primarily with reference to Bluetooth Low Energy (BLE), it will be appreciated that other suitable protocols may alternatively be used. Such protocols may include 802.11 wireless local area network ro protocols, other types of Bluetooth protocol. Ultra wideband (UWB) protocols or Zigbee protocols.

As will be appreciated, the apparatuses 12, 10-2, 10-3, 11A, 13 described herein may include various components which have may not been shown in the Figures.

/5 The apparatuses 12, 10-2, 10-3, 11A, 13 may comprise further optional SW components which are not described in this specification since they may not have direct interaction to embodiments of the invention.

Embodiments of the present invention may be implemented in software, hardware, application logic or a combination of software, hardware and application logic. The software, application logic and/or hardware may reside on memory, or any computer media. In an example embodiment, the application logic, software or an instruction set is maintained on any one of various conventional computer-readable media. Tn the context of this document, a "memory" or "computer-readable medium" may be any media or means that can contain, store, communicate, propagate or transport the instructions for use by or in connection with an instruction execution system, apparatus, or device, such as a computer.

Reference to, where relevant, "computer-readable storage medium", "computer program product", "tangibly embodied computer program" etc, or a "processor" or "processing circuitry" etc. should be understood to encompass not only computers having differing architectures such as single/multi processor architectures and sequencers/parallel architectures, but also specialised circuits such as field programmable gate arrays FPGA, application specify circuits ASIC, signal processing devices and other devices. References to computer program, instructions, code etc. should be understood to express software for a programmable processor firmware such as the programmable content of a hardware device as instructions for a processor or configured or configuration settings for a fixed function device, gate array, programmable logic device, etc. As used in this application, the term 'circuitry' refers to all of the following: (a)hardware-only circuit implementations (such as implementations in only analogue and/or digital circuitry) and (b) to combinations of circuits and software (and/or firmware), such as (as applicable): (i) to a combination of processor(s) or (ii) to portions of processor(s)/software (including digital signal processor(s)), software, and memory(ies) that work together to cause an apparatus, such as a mobile phone or server, to perform various functions) and (c) to circuits, such as a microprocessor(s) or a portion of a microprocessor(s), that require software or firmware for operation, even if the software or firmware is not physically present.

This definition of circuitry' applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term "circuitry" would also cover an implementation of merely a processor (or multiple processors) or portion of a processor and its (or their) accompanying software and/or firmware. The term "circuitry" would also cover, for example and if applicable to the particular claim element, a baseband integrated circuit or applications processor integrated circuit for a mobile phone or a similar integrated circuit in server, a cellular network device, or other network device.

If desired, the different functions discussed herein may be performed in a different order and/or concurrently with each other. Furthermore, if desired, one or more of the above-25 described functions may be optional or may be combined.

Although various aspects of the invention are set out in the independent claims, other aspects of the invention comprise other combinations of features from the described embodiments and/or the dependent claims with the features of the independent claims, and not solely the combinations explicitly set out in the claims.

It is also noted herein that while the above describes various examples, these descriptions should not be viewed in a limiting sense. Rather, there are several variations and modifications which may be made without departing from the scope of the present invention as defined in the appended claims.

Claims

Claims 1. A method comprising: determining that an absence of communication between a first radio communication apparatus and a second radio communication apparatus for longer than a pre-determined duration has occurred; and responding to the determination by causing transmission to at least one recipient radio communication apparatus of a search instruction for causing the recipient radio communication apparatus which receives the search instruction to be set into a search ro mode in which the recipient radio communication apparatus is responsive to detection of an occurrence of communication between the recipient radio communication apparatus and the second radio communication apparatus to perform at least one operation.
2. The method of claim 1, comprising responding to the determination that /5 communication between the first radio communication apparatus and the second radio communication apparatus has not occurred for longer than the pre-determined duration by: identifying, from a plurality of available recipient communication apparatuses, a set of one or more recipient radio communication apparatuses based on a characteristic associated with the second radio communication apparatus and/or a characteristic associated with the set of one or more recipient radio communication apparatuses, the identified set including the recipient radio communication apparatus; and causing transmission of the search instruction to each of the recipient communication apparatuses in the identified set.
3. The method of claim 1 or claim 2, wherein the search instruction includes information identifying the second radio communications apparatus.
4. The method of any preceding claim wherein setting the recipient radio communication apparatus into search mode includes the recipient radio communication apparatus initiating a scan for the second radio communication apparatus.
5. The method of claim 4, wherein the scan is initiated on the basis of information included in the search instruction which identifies the second radio communication 35 apparatus.
6. The method of any preceding claim, wherein the search instruction includes information based on which the at least one operation that is to be performed by the recipient radio communication apparatus can be determined.
7. The method of any preceding claim, wherein the determining that the absence of communication for longer than the pre-determined duration has occurred comprises: noting an instant at which a most-recent communication between the first and second mobile radio communication apparatus took place; and detecting when a period of time since the noted instant exceeds the pre-ro duration.
8. The method of claim 7, wherein the pre-determined duration is dependent on a characteristic associated with the second communication apparatus.is
9. A method comprising: responding to receipt by a recipient radio communication apparatus of a search instruction by setting the recipient radio communication apparatus into a search mode in which the recipient radio communication apparatus is responsive to detection of an occurrence of communication between the recipient radio communication apparatus and another radio communication apparatus by causing performance of at least one operation.
10. The method of claim 9, wherein the another radio communication apparatus is identified in the search instruction.
11. The method of claim 9 or claim 10, wherein setting the recipient communication apparatus into search mode includes initiating a scan for incoming transmissions.
12. The method of claim 11, wherein initiating the scan comprises at least one of: causing transmission by the recipient radio communication apparatus of data 30 packets addressed to the another radio communication apparatus; and causing the recipient radio communication apparatus to listen for data packets received from the another radio communication apparatus.
13. The method of any of claims 9 to 12, comprising determining the at least one operation based on information included in the received search instruction.
14. The method of any of claims 9 to 13, wherein the at least one operation includes notifying the apparatus from which the search instruction was received that the communication between the recipient radio communication apparatus and the another radio communication apparatus has occurred.
15. The method of claim 14, wherein the communication between the recipient radio communication apparatus and another radio communication apparatus is performed using a first wireless communication protocol and notifying the apparatus from which the search instruction was received is performed using a second, different wireless ro communication protocol.
16. The method of any of claims 9 to 15 wherein the at least one operation includes providing an alert for notifying the user of the recipient radio communication apparatus.
17. The method of any of claims 9 to 16, wherein setting the recipient communication apparatus into the search mode includes activating at least one radio component of the recipient radio communication apparatus.
18. The method of any of claims 9 to 16, comprising: subsequent to causing performance of the at least one operation, disabling at least one radio component of the recipient radio communication apparatus.
19. Apparatus configured to perform a method according to any of claims 1 to 18.
20. Computer-readable instructions, which when executed by computing apparatus cause the computing apparatus to perform a method according to any of claims 1 to 18.
21. Apparatus comprising: at least one processor; and at least one memory having computer readable instructions stored thereon which, when executed by the at least one processor, cause the apparatus: to determine that an absence of communication between a first radio communication apparatus and a second radio communication apparatus for longer than a pre-determined duration has occurred; and to respond to the determination by causing transmission to at least one recipient radio communication apparatus of a search instruction for causing the recipient radio communication apparatus which receives the search instruction to be set into a search mode in which the recipient radio communication apparatus is responsive to detection of an occurrence of communication between the recipient radio communication apparatus and the second radio communication apparatus to perform at least one operation.
22. The apparatus of claim 21, wherein the computer readable code, when executed by the at least one processor, causes the apparatus: to respond to the determination that communication between the first radio communication apparatus and the second radio communication apparatus has not occurred for longer than the pre-determined duration by: ro identifying, from a plurality of available recipient communication apparatuses, a set of one or more recipient radio communication apparatuses based on a characteristic associated with the second radio communication apparatus and/or a characteristic associated with the set of one or more recipient radio communication apparatuses, the identified set including the recipient radio communication apparatus; and causing transmission of the search instruction to each of the recipient communication apparatuses in the identified set.
23. The apparatus of claim 21 or claim 22, wherein the search instruction includes information identifying the second radio communications apparatus.
24. The apparatus of any of claims 21 to 23, wherein setting the recipient radio communication apparatus into search mode includes the recipient radio communication apparatus initiating a scan for the second radio communication apparatus.
25. The apparatus of claim 24, wherein the scan is initiated on the basis of information included in the search instruction which identifies the second radio communication apparatus.
26. The apparatus of any of claims 21 to 25, wherein the search instruction includes information based on which the at least one operation that is to be performed by the recipient radio communication apparatus can be determined.
27. The apparatus of any of claims 21 to 26, wherein the computer readable code, when executed by the at least one processor, causes the apparatus: to note an instant at which a most-recent communication between the first and second mobile radio communication apparatus took place; and to detect when a period of time since the noted instant exceeds the pre-determined duration thereby to determine that the absence of communication for longer than the predetermined duration has occurred.
28. The apparatus of claim 27, wherein the pre-determined duration is dependent on a characteristic associated with the second communication apparatus.
29. Apparatus comprising: at least one processor; and ro at least one memory having computer readable instructions stored thereon which, when executed by the at least one processor, cause the apparatus: to respond to receipt by a recipient radio communication apparatus of a search instruction by setting the recipient radio communication apparatus into a search mode in which the recipient radio communication apparatus is responsive to detection of an /5 occurrence of communication between the recipient radio communication apparatus and another radio communication apparatus by causing performance of at least one operation.3o. The apparatus of claim 29, wherein the another radio communication apparatus is identified in the search instruction.31. The apparatus of claim 29 or claim 3o, wherein setting the recipient communication apparatus into search mode includes initiating a scan for incoming transmissions.32. The apparatus of claim 3o, wherein initiating the scan comprises at least one of: causing transmission by the recipient radio communication apparatus of data packets addressed to the another radio communication apparatus; and causing the recipient radio communication apparatus to listen for data packets received from the another radio communication apparatus.33. The apparatus of any of claims 29 to 32, wherein the computer readable code, when executed by the at least one processor, causes the apparatus to determine the at least one operation based on information included in the received search instruction.34. The apparatus of any of claims 29 to 33, wherein the at least one operation includes notifying the apparatus from which the search instruction was received that the communication between the recipient radio communication apparatus and the another radio communication apparatus has occurred.35. The apparatus of claim 34, wherein the communication between the recipient radio communication apparatus and another radio communication apparatus is performed using a first wireless communication protocol and the notifying the apparatus from which the search instruction was received is performed using a second, different wireless communication protocol.ro 36. The apparatus of any of claims 29 to 35 wherein the at least one operation includes providing an alert for notifying the user of the recipient radio communication apparatus.37. The apparatus of any of claims 29 to 36, wherein setting the recipient communication apparatus into search mode includes activating at least one radio /5 component of the recipient radio communication apparatus.38. The apparatus of any of claims 29 to 37, wherein the computer readable code, when executed by the at least one processor, causes the apparatus: subsequent to causing performance of the at least one operation, to disable at least one radio component of the recipient radio communication apparatus.39. A non-transitory computer-readable memory medium having computer readable code stored thereon, which when executed by computing apparatus, causes the computing apparatus: to determine that an absence of communication between a first radio communication apparatus and a second radio communication apparatus for longer than a pre-determined duration has occurred; and to respond to the determination by causing transmission to at least one recipient radio communication apparatus of a search instruction for causing the recipient radio communication apparatus which receives the search instruction to be set into a search mode in which the recipient radio communication apparatus is responsive to detection of an occurrence of communication between the recipient radio communication apparatus and the second radio communication apparatus to perform at least one operation.4o. A non-transitory computer-readable memory medium having computer readable code stored thereon which, when executed by computing apparatus, causes the computing apparatus: to respond to receipt by a recipient radio communication apparatus of a search instruction by setting the recipient radio communication apparatus into a search mode in which the recipient radio communication apparatus is responsive to detection of an occurrence of communication between the recipient radio communication apparatus and another radio communication apparatus by causing performance of at least one operation.Apparatus comprising: means for determining that an absence of communication between a first radio communication apparatus and a second radio communication apparatus for longer than a ro pre-determined duration has occurred; and means for responding to the determination by causing transmission to at least one recipient radio communication apparatus of a search instruction for causing the recipient radio communication apparatus which receives the search instruction to be set into a search mode in which the recipient radio communication apparatus is responsive to /5 detection of an occurrence of communication between the recipient radio communication apparatus and the second radio communication apparatus to perform at least one operation.42. Apparatus comprising: means for responding to receipt by a recipient radio communication apparatus of a search instruction by setting the recipient radio communication apparatus into a search mode in which the recipient radio communication apparatus is responsive to detection of an occurrence of communication between the recipient radio communication apparatus and another radio communication apparatus by causing performance of at least one operation.