KR20070022118A - A method and a system for operating an ambiance listening mode in a wireless communication system - Google Patents

Abstract

The system includes a monitoring communication unit 107 that performs an environment listening service with respect to the monitored communication unit 101. The monitored communication system 101 includes a transmitter 109 that sends an environmental listening mode transmission to the monitoring communication unit 107, which includes a receiver 117 receiving it. In addition, the monitoring communication unit 107 includes command controllers 119 and 121 for determining and transmitting transmission parameter commands to the monitored communication unit 101, which are received by the receiver 113. The monitored communication unit 101 includes a transmission controller 115 which sets at least one transmission parameter of the environment listening mode transmission according to the transmission parameter command. The monitoring transmission unit 107 thus controls the transmission aspect from the monitored communication unit 101 and in particular controls the reduced transmission power or transmission time to reduce power consumption, heating and interference.

Monitoring communication unit, transmission parameter command, environmental listening mode transmission, transmission controller, transmission side

Description

A method and a system for operating an ambiance listening mode in a wireless communication system

The present invention relates to a method and system for operating an environmental listening mode in a wireless communication system, but is not limited thereto, in particular for operating an environmental listening mode in a cellular communication system, such as a TETR (Terrestrial Trunked RAdio) communication system. will be.

In a cellular communication system, the geographic area is divided into a plurality of respective cells provided by a base station. The base stations are interconnected by a fixed network that can communicate data between the base stations. The remote unit provided via wireless communication is linked by the base station of the cell within the range in which the remote unit is located.

As the remote unit moves, it can be moved from the range of one base station to the range of another base station, ie from one cell to another. As the remote unit heads to a new base station, it enters the redundant range of the two base stations and changes what is supported by the new base station within this redundant range. As the remote unit moves further into the new cell, support continues at the new base station. This is known cell reselection or handover.

The communication from the remote unit to the base station is known as the uplink and the communication from the base station to the remote unit is known as the downlink.

This fixed network interconnecting the base stations can transmit data between any two base stations, allowing the remote unit of the cell to communicate with the mobile station of any other cell. In addition, the fixed network includes a gateway function that can interconnect with an external network, such as a public switched telephone network (PSTN), allowing the remote unit to communicate with landline telephones and other communication terminals connected by landline. In addition, fixed networks include many of the functionality required to maintain conventional cellular communication networks, including functionality such as data routing, admission control, resource reallocation, subscriber billing, mobile station authentication, and the like.

Examples of cell phone communication systems include both public cell phone communication systems, such as Global System for Mobile Communications (GSM), and specialized mobile radio (PMR), such as TETR (Terrestrial Trunked RAdio).

In particular, although TETRA is used in public cellular communication systems, it is designed to provide a number of features and services that are particularly suitable for private groups or groups, for example emergency services.

TETRA, for example, provides a number of features and services for maintaining or controlling group calls as well as for managing membership of these groups. Thus, TETRA provides a service for making group calls, for example, voice messages are quickly and efficiently relayed to specific groups of remote units. TETRA also provides features to manage membership of other groups, priority of other groups, and so on. In addition, TETRA provides both approved and unauthorized communications. Regarding the authorized service, the call set up includes a call originator receiving an acknowledgment indicating whether the destination has been reached. However, for unapproved services, there is no acknowledgment received from the destination.

Other features and services provided by TETRA include a high level of security optimized for specific purposes, pressed talk channel assignments, broadcast calls, and direct mode of operation (DMO), where the remote unit can communicate directly without the need for a base station or the like. have.

One additional service proposed to TETRA is the environmental listening service. The environmental listening service allows an authenticated user to establish a call with a particular remote unit without any hint of whether such activity occurs to monitor sound activity in the vicinity of the remote unit. This environment listening service allows an authenticated user to listen to the sound environment of the remote unit without being visible to the neighboring users or people of the remote unit.

Environmental listening is typically intended to enhance the security and safety of the user. The authenticated user will typically be the control center for the organization operating the TETRA network. For example, with respect to a TETRA system operated by law enforcement organizations such as police, the central control center will typically be assigned to an authorized user status who can listen to individual law enforcement remote units. For example, if the central control center has received an alert from a remote unit or suspects an emergency will occur, environmental listening can help determine what the central control center is and choose appropriate measures. have.

Typically, individual users of remote units are prohibited from using environmental listening. However, if environmental listening is allowed from the remote unit, the environmental listening is normally activated or stopped by the authenticated user by sending an activation command to the remote unit.

Although the environmental listening service provides a number of advantages and enhances the safety and security of the remote unit user, it also has some disadvantages with respect to supporting the environmental listening service.

For example, to receive an environmental sound signal from a remote unit, it must continuously transmit to an authenticated user. Thus, the traffic channel is continually dominated by this transmission. This not only causes interference and reduces the overall capability of the communication system, but also affects the remote unit itself. One effect of this transmission is related to severe power consumption due to severe battery depletion. Thus, listening to the environment is inconvenient for the user because it reduces battery life and this power depletion typically occurs without the user's knowledge. This results in the battery discharging without the user doing anything, allowing the user to use the remote unit in an emergency as possible.

In addition, transmission in environmental listening will increase power loss due to heating of the remote unit. Even if the increase in temperature is not large, it may be possible for a person to determine that a transmission is taking place. Thus, heating allows a person to sense that the environmental listening service has been activated in a number of undesirable situations.

Thus, a system that is improved for the environmental listening mode is desirable and in particular a system that is capable of increasing flexibility, increasing control, reducing power consumption, and allowing increased confidentiality and / or improved performance.

Accordingly, the present invention seeks to advantageously alleviate, alleviate or eliminate one or more of the above mentioned disadvantages one by one or in any combination.

According to a first aspect of the invention the present invention provides a system for operating an environmental listening mode in connection with a monitored communication unit and a monitored communication unit in a wireless communication system; The system comprises: a monitoring communication unit having means for receiving an environment listening mode transmission from the monitored communication unit, means for transmitting at least one transmission parameter command to the monitored communication unit and a monitoring communication unit for monitoring the environmental listening mode transmission Means for transmitting at least one transmission parameter command from the monitoring communication unit, and means for setting at least one transmission parameter of the environment listening mode transmission in response to the at least one transmission parameter command. It includes a communication unit.

The present invention can provide improved performance when operating an environmental listening service. The monitoring communication unit can be associated with an authorized user who can monitor the sound environment without the user being aware of such activity. In this way, the monitoring communication unit and the authenticated user can control at least one transmission parameter of the monitored communication unit, thereby remotely controlling the transmission characteristics. The monitoring communication unit can control transmission parameters suitable for the current operating state, the propagation environment and / or the sensing importance or the criticality of the monitoring. For example, the transmission parameters may be adjusted by a monitoring communication unit that dynamically optimizes the tradeoffs between resource usage and quality of monitoring. The transmission parameters may be suitable for various environments that reduce power consumption or heating of the remote unit while allowing quality degradation. This may improve battery life and / or reduce the likelihood that monitoring activity may be detected at the monitored remote unit. In some embodiments of the invention, the at least one transmission parameter reduces the level of interference and improves the overall capabilities of the communication system.

According to an optional feature of the invention, the at least one transmission parameter comprises a continuous parameter of environment listening mode transmission.

The monitored communication unit can be switched between continuous transmission mode and discontinuous transmission mode in response to a transmission parameter command. In continuous mode, the traffic channel assigned to the environment listening can be used completely, for example the appropriate time slot of the channel is used for data transmission from the monitored communication unit to the monitoring communication unit. In the discontinuous mode, the traffic channel assigned to the environment listening is only partially used, for example some suitable time slot of the channel is used for data transfer from the monitored communication unit to the monitoring communication unit. This can provide an efficient and conciseness for implementing means to reduce power consumption, temperature increase and interference for environmental listening services.

According to an optional feature of the invention, the at least one transmission parameter comprises a transmission power parameter. For example, the transmit power can be reduced when the quality of environmental listening is less important because, for example, the monitored sound does not represent an emergency. This feature can provide an efficient and concise way to implement a scheme for reducing power consumption, temperature increase and interference for environmental listening services.

According to an optional feature of the invention, the means for transmitting the environmental listening mode transmission is capable of a discontinuous transmission operation and the at least one transmission parameter comprises a time characteristic of the at least one discontinuous transmission. The change in the time characteristic with respect to discontinuous transmission provides a suitable way to optimize the transmission characteristic of the environmental listening mode transmission, in particular. Typically, changes in time characteristics are simple to provide and to achieve significant performance.

According to an optional feature of the invention, the time characteristic comprises a duration of at least one discontinuous transmission. This provides a concise and efficient implementation, particularly suitable for various embodiments.

According to an optional feature of the invention, the time characteristic comprises the interval between discontinuous transmissions. This provides a concise and efficient implementation, particularly suitable for various embodiments. For example, changing the time interval between successive discontinuous transmissions provides simple and efficient control. By way of example, in a TETRA communication system, the means for setting at least one transmission parameter generates one or more time slots to be skipped upon receiving a transmission parameter command. This transmission parameter command may indicate how many frames should be skipped between transmissions from a particular monitored communication unit.

According to an optional feature of the invention, the monitored communication unit comprises means for transmitting operating parameter information to the monitoring communication unit. This may provide additional information to the monitoring communication unit and / or the authenticated user, thereby allowing the authenticated user to control the operation of the monitoring communication unit and / or the monitored communication unit.

According to an optional feature of the invention, the monitoring communication unit comprises means for generating at least one transmission parameter command in accordance with the operating parameter information. This allows for improved setting of at least one transmission parameter since the transmission parameter command can be selected to reflect the current operating state of the monitored communication unit. For example, the transmission parameter command can be selected automatically or semi-automatically in the monitored communication unit.

According to an optional feature of the invention, the operating parameter information includes an operating temperature indication of the monitored communication unit. This improves the characteristic control of the monitored communication unit by controlling by the monitoring communication unit at least one transmission parameter in accordance with the operating temperature of the monitored communication unit. For example, if the temperature of the monitored communication unit increases above a certain threshold, the transmit power is reduced.

According to an optional feature of the invention, the operating parameter information includes a battery charge indication of the monitored communication unit. This improves the characteristic control of the monitored communication unit by being controlled by the monitoring communication unit according to the battery charging of the communication unit in which the at least one transmission parameter is monitored. For example, if battery charging is below a predetermined threshold, then the transmit power is reduced and / or increased intervals between transmissions are applied. The battery charge indication may indicate, for example, the charge remaining in the battery power of the monitored communication unit.

According to an optional feature of the invention, the operating parameter information includes an external power connection indication for the monitored communication unit. For example, the external power connection indication indicates whether the monitored communication unit is coupled to an external power source or powered by an internal battery. Improved control of the transmission characteristics of the monitored communication unit can be achieved and in particular the transmission characteristics are optimized to reflect whether a limited battery power source or typically a non-limiting external power source powers the monitored communication unit.

According to an optional feature of the invention, the operating parameter information includes an operating mode indication for the monitored communication unit. This allows the optimization of at least one transmission parameter to be in accordance with the current mode of operation of the communication unit being monitored. For example, environmental listening may be performed even if the monitored communication unit is switched and thus the transmission characteristic is changed to reflect whether the monitored communication unit is in the on mode of operation or the off mode of operation.

According to an optional feature of the invention, the monitoring communication unit comprises means for sending an operating parameter information request message to the monitored communication unit and the monitored communication unit is operative to transmit the operating parameter information in response to receiving the operating parameter information request message. do. This allows to provide an efficient system for communicating operating parameter information and to make the monitoring communication unit controllable when this information is provided.

According to an optional feature of the invention, the monitored communication unit is allowed to operate in a first mode of operation and a second mode of operation and at least one transmission parameter is applied to the transmission of the second mode of operation rather than the first mode of operation. In particular, the first mode of operation may be a complete monitoring operation and the second mode of operation may be a reduced monitoring mode. The monitored communication unit can be operated in a first mode of operation, for example a conventional environmental listening is provided but can also be switched to a second mode of operation and for example temperature increase, power consumption and / or interference are reduced.

According to an optional feature of the invention, the monitoring communication unit may be operable to send the changed monitoring mode of operation request to the monitored communication unit and the monitored communication unit is to enter the second mode of operation upon receiving the changed monitoring mode of operation request. It can work. This provides an efficient way for the monitoring communication unit and the authenticated user to control the operation of the monitored communication unit. The monitored communication unit may transmit operating parameter information upon receiving an operation mode request to provide confirmation and information of the operating state of the monitored communication unit when entering the second operating mode.

According to an optional feature of the invention, the monitored communication unit comprises means for switching between the first mode of operation and the second mode of operation in accordance with the monitored environmental sound characteristics. This makes the way for the change of transmission characteristics to be suitable for the current state to be efficient and convenient. In particular, the second mode of operation enters when the environmental sound characteristics indicate relatively quiet and exits when this quiet ends.

According to an optional feature of the invention, the environmental sound characteristic being monitored is a voice detection characteristic. This reduces power consumption and interference in the absence of voice activity, but is particularly suitable for environmental sound characteristics as it allows full environmental listening in the presence of voice activity in the surrounding environment of the monitored communication unit. Thus, when environmental listening is less important, it reduces resource consumption, but when it becomes important, improved environmental listening quality is obtained.

According to an optional feature of the invention, the switching means is operative to activate the sound operational mode if the monitored environmental sound characteristic exhibits a sound level below the volume threshold for a predetermined duration. This provides an efficient and concise way to determine suitable environmental sound characteristics for switching to the second mode of operation.

According to an optional feature of the invention, the switching means is operative to set the duration according to at least one transmission parameter command. This makes it possible to improve the operation control of the monitored communication unit when the monitoring communication unit and the authenticated user are in the environmental listening mode.

According to an optional feature of the invention, the monitored communication unit comprises means for sending a status indication message in a second mode of operation rather than a first mode of operation. This allows status indication messages to be sent when they are most appropriate. For example, in the second mode of operation, some or all of the environment listening mode transmission may be replaced by a status indication message without causing fatal to an authenticated user.

The wireless communication system may be a cellular communication system, in particular a TETRA (Terrestrial Trunked RAdio) system.

According to a second aspect of the invention, there is provided an apparatus for operating an environmental listening mode in connection with a telecommunications unit in a wireless communication system; The apparatus comprises: means for receiving an environment listening mode transmission from a telecommunications unit; And means for sending at least one transmission parameter command to the remote unit, wherein the at least one transmission parameter command indicates that a transmission parameter setting is used by the remote command when the environment listening mode transmission is transmitted.

According to a third aspect of the invention, there is provided an apparatus for operating an environmental listening mode in connection with a monitoring communication unit in a wireless communication system; The apparatus comprises: means for sending an environmental listening mode transmission to a monitoring communication unit; Means for receiving at least one transmission parameter command from the monitoring communication unit; And means for setting at least one transmission parameter of an environment listening mode transmission in accordance with the at least one transmission parameter command.

According to a fourth aspect of the invention, there is provided a method of operating an environmental listening mode in connection with a monitored communication unit and a monitored communication unit in a wireless communication system; The method includes: at a monitoring communication unit: receiving an environment listening mode transmission from the monitored communication unit, and sending at least one transmission parameter command to the monitored communication unit; And at the monitored communication unit: sending the environment listening mode transmission to the monitoring communication unit, receiving at least one transmission parameter command from the monitoring communication unit, and according to the at least one transmission parameter command. Setting at least one transmission parameter of an environment listening mode transmission.

In these and other aspects, the features and advantages of the present invention will become apparent from the following description with reference to the embodiments described below.

Embodiments of the invention will be described with reference to the drawings, by way of example only.

1 illustrates an example of a TETRA cellular communication system integrated into an embodiment of the present invention.

2 illustrates an exemplary signal flow diagram in accordance with an embodiment of the present invention.

The following description focuses on an embodiment of the present invention that can be applied to an environmental listening service of a TETR (Terrestrial Trunked Radio) mobile phone communication system. However, it will be appreciated that the present invention is not limited to this application and can be applied to many other wireless communication systems.

1 illustrates an example of a TETRA cellular telephone communication system in which an embodiment of the present invention is incorporated.

TETRA is a time division multiple access (TDMA) system and the 25 kHz wide carrier is further divided into four individually assignable time slots. Each time slot has a duration of 14.167 msecs and the four time slots are combined into a time frame with a duration of 56.67 msec. Each of the four time slots in the time frame may be individually located to the same or different remote unit. In addition, the time frames are combined into multiframes having 18 time frames. Frame number 18 is reserved as a control frame and control information is communicated during call activation.

In the system of FIG. 1, the TETRA remote unit 101 is in communication with the TETRA base station 103 over the TETRA air air interface. Base station 103 is coupled with a fixed network 105 that connects another base station (not shown) with another network (not shown). The fixed network 105 is coupled to the control unit 107. The control unit 107 is in the embodiment of FIG. 1, where the control unit of the organization's central dispatch center uses the TETRA communication system for communication services between a large number of individual users. For example, the central control center may be a central control center for law enforcement organizations such as police.

In an embodiment, the central control center preferably uses the TETRA environmental listening service in some situations. For example, when an alert is received from the remote unit 101, the operator of the central control center sets up an environment listening operation for the remote unit 101 to obtain more information of the situation in which the alert occurred. In this way the operator can get more information without the user having to operate the remote unit. When the environment listening service is set up, both the remote unit 101 and the control unit 107 enter the environment listening mode.

According to the embodiment of FIG. 1, the operation of the remote unit 101 is influenced or controlled by the control unit 107 in the environmental listening mode operation. In particular, the control unit 107 controls one or more transmission parameters from the remote unit 101 to the base station 103.

In accordance with the embodiment of FIG. 1, the remote unit 101 includes a transmitter 109 that sends the environmental listening mode transmission to the monitoring communication unit. In an embodiment, the transmitter 109 receives the input from the microphone 111 of the remote unit 101, encodes the signal and sends the environmental listening data result to the base station 103 via the TETRA air interface. The environmental sound data is then routed from the base station 103 to the control unit 107 via the fixed network 105. Thus, in the present embodiment, the environmental sound data is not indirectly transmitted to the control unit 107 via the air interface, but indirectly through the base station 103 and the fixed network 105. In some embodiments, the control unit 107 and the base station 103 may be integrated, and the transmission of environmental sound data may go to the control unit 107 via a direct air interface without including the fixed network 107. I will understand that.

The ambient sound encoding and the transmission of the resulting data of the embodiment of FIG. 1 are performed according to the TETRA technical specification as is known in the art and will not be described any further because it is concise and clear.

The remote unit 101 includes a receiver operative to receive a transmission parameter command from the remote unit 107. The transmission parameter command is transmitted from the control unit 107 via the fixed network 105 and the base station 103. The remote unit 101 further includes a transmission controller 115 coupled with the receiver 113 and the transmitter 109. The transmission controller 115 receives the transmission parameter command from the receiver 113 and operates to control one or more transmission parameters of the transmission of the environmental sound data in accordance with the transmission parameter command.

The control unit 107 includes a receiver 117 which receives the environmental sound data transmission from the remote unit 101 via the base station 103 and the fixed network 105.

Receiver 107 receives environmental sound data and generates a sound signal, which is provided to the operator, for example, via a speaker, headset or other suitable user interface means.

The receiver 117 is also connected to the environmental listening controller 119 of the embodiment of FIG. 1, which is supplied with environmental listening service, environmental sound data and / or operational information related to the remote unit 101 as described below. The environmental listening controller 119 is operative to determine a desired remote transmission characteristic or parameter of the environmental sound data transmission from the remote unit 101.

The control unit 107 includes a command controller 121 supplied with a desired remote transmission characteristic from the environment listening controller 119. The command controller 121 thus generates one or more transmission parameter commands that are sent to the remote unit 101 via the fixed network 105 and the base station 103.

According to the embodiment of FIG. 1, the control unit 107 constitutes a monitoring communication unit for an environment listening service which constitutes a communication unit to which the remote unit 101 is monitored. In addition, in addition to the promotion and termination of the environment listening operation, the control unit 107 can change the call transmission method of the remote unit 101 to be monitored. Thus, the control unit 107 can generate a transmission parameter command when the transmission parameter is set accordingly when received by the remote unit. Thus, additional control is provided in the control unit to improve performance and flexibility. In particular, the control unit 107 can generate a transmission parameter command so that the transmission parameter can be changed to match the current state.

In some embodiments the determination of the transmission parameter command and / or the desired transmission parameter may be determined by the control unit 107 according to a suitable algorithm. However, in other embodiments, the transmission parameters and / or the desired transmission parameters may be determined semi-automatically or manually. For example, the environment listening controller 119 may be implemented with user interface means by which the operator directly enters the desired absolute or relative transmission parameter and / or transmission parameter command. In some such embodiments, the user interface also provides the user with information regarding the status or characteristics of the environmental listening service or remote unit 101 to allow the user to select a suitable transmission parameter or transmission parameter command according to these parameters. The user interface includes, for example, a display, a keyboard and / or a pointing device.

It will be appreciated that the transmission parameters that can be changed in other embodiments may depend on the specific characteristics and requirements associated with the individual embodiments. In the following, examples of transmission parameters that can be influenced or controlled individually or in combination from the monitoring communication unit are described with particular reference to the embodiment of FIG. 1.

In some embodiments, the control unit 107 may remotely control or influence the transmit power parameter. In particular, the power of the environmental listening sound data transmission can be controlled by the control unit 107 transmitting the transmission parameter command as the transmission controller 115 determines the appropriate transmission power. The transmission parameter command may directly instruct the transmission controller 115 to set the transmission power by increasing or decreasing the transmission power to a predetermined level or by a predetermined amount.

This allows the control unit 107 to reduce the transmission power in situations that may allow for deterioration of the quality of the environmental listening signal. For example, if ambient sound is not heard, the transmit power is temporarily reduced to reduce the power consumption and temperature of the remote unit 101 as well as reduce the interference generated. Although increased noise may be introduced, it will generally be acceptable for a quiet time.

In some embodiments, the control unit 107 may remotely control or influence the data rate of environmental listening data. The data rate can be varied by varying the source encoding rate and / or the channel encoding rate. For example, the data rate can be reduced during quiet time to degrade the quality but accept the signal. For example, the remote unit 101 can switch between high data rate sound (voice) encoders and low data rate sound (voice) encoders and these according to transmission parameter commands received from the control unit 107. It includes. Equally, remote unit 101 includes a fast channel encoder and a slow channel encoder and a transmission controller capable of switching between them in accordance with transmission parameter commands.

In some embodiments, the transmission controller may change a number of parameters in combination and dependent on each other. For example, the transmission parameter command includes a command to command the remote unit 101 to switch to the static mode of operation. When this command is received, the transmission controller 115 can control that the transmitter 109 switches to a low data rate source encoder and to a high speed channel encoder (preferably to the same channel data rate as before). . Increased channel encoding allows transmission to be performed at significantly lower transmit power, which significantly reduces power consumption, temperature increase and interference. In addition, a reliable ambient sound signal is received at the control unit 107 although the quality is degraded due to the reduced source data rate.

In some embodiments, continuous parameters of environment listening data transmission may be controlled according to transmission parameter commands. For example, the transmission controller 115 may switch between continuous transmission of environmental listening data and intermittent transmission of environmental listening data in response to receiving an appropriate transmission parameter command.

In some embodiments, the environment listening data may be transmitted discontinuously or intermittently, and the time characteristic of the discontinuous transmission may be changed. For example, the duration of the transmission can be increased or decreased by the control unit 107 sending the appropriate transmission parameter command to the remote unit 107. In some such embodiments, the source encoder may generate organized data in order of decreasing importance. Within each sound encoding frame, a first group of data bits, which are indispensable for reproducing the encoded sound, is created and a second group of data bits, which is important for reproducing the sound without significant quality degradation, is encoded and provides only a relatively small quality improvement. The third group of data bits is encoded. In this embodiment, the transmission parameter command can be transmitted from the control unit 107 so that the transmission duration of the environment listening data causes only the first data group to be transmitted. This lowers power consumption, temperature increase and interference but allows low quality sound to be reproduced in the control unit 107 and is suitable for, eg, quieting. Other transmission parameter commands are sent when improved quality is required. This command will increase the duration and also include the second group of data bits. As a result, the third transmission parameter command is transmitted by setting a duration for all data bits to be transmitted, which consumes the highest quality but increased power consumption and interference.

Alternatively or additionally, the interval between discontinuous transmissions can be controlled or influenced by the control unit 107. For example, the duration of individual data transfers remains substantially constant while the effective data rate of environmental listening data can be varied by varying the interval between successive data transfers.

In the TETRA embodiment the environment listening traffic channel is configured by repeating the time slots, and the interval between transmissions of the environment listening data can be achieved by omitting the transmission of data in other time slots. For example, the transmission parameter command may be used by the control unit 107 to cause the environment listening data transmission to use every time slot, every second time slot, or every fourth time slot. In this way, the control unit 107 can control the effective data rate of the environmental listening data transmission from the remote unit 101 to control the compromise between environmental listening quality and power consumption, heating and interference.

Since the parameters of some embodiments are fully controlled by the control unit 107, it will be appreciated that the transmission parameter commands of other embodiments are included as determining parameters of the transmission parameters. In particular, the transmission controller 115 can operate an algorithm for suitable transmission parameters, including consideration of a number of characteristics, parameters, and commands. Thus, the transmission parameter command may be just one of a number of input parameters used by an algorithm to select and set a suitable parameter value.

The control unit 107 thus controls or influences a number of parameters, resulting in a reduction in resource consumption associated with the transmission of environmental listening data. In particular, it reduces power consumption and battery depletion and temperature rise by reducing the transmission power or effective transmission time (or duty cycle) of the environmental listening data transmission. In addition, the average interference caused by transmission is reduced to improve the capability throughout the communication system. In addition, environmental listening services are still supported with reduced resource consumption. In addition, the control unit may control the compromise between resource usage and environmental listening quality, and may be optimized to provide environmental listening performance deemed necessary for an authenticated user for the current situation. In particular, this approach reduces the resource usage when the authenticated user cannot compromise quality if it is essential to be considered, but when environmental listening does not need to be taken seriously. Thus, an authenticated user can complete the environmental listening task without severe heating of the remote unit 101 or battery drain.

In some embodiments, the remote unit 101 can be operated in two environmental listening transmission modes under the control of the transmission controller 115. In some such embodiments, the received transmission parameter command may be adjusted to operate in one mode of operation rather than the other. For example, remote unit 101 may generally operate in a full environmental listening mode and all available resources may be used or in reduced environmental listening mode and remote unit 101 may operate in less resource demand mode. For example, only with a subset of the available time slots and / or with reduced transmit power.

In some embodiments, certain transmission parameter commands may be applied to only one of the modes of operation. For example, a transmission parameter command may be sent indicating that the remote unit 107 should skip every other time slot when transmitted in the reduced mode of operation. The transmission parameter command may optionally be combined with a command for the remote unit 101 to enter a reduced mode of operation.

In some such embodiments, it will be understood that some transmission parameter commands relate only to the first mode of operation, some transmission parameter commands relate only to the second mode of operation, and some transmission parameter commands relate to both the first and second modes of operation. will be.

In some such embodiments, the transmission controller 115 operates to control the mode of operation of the remote unit 101 in accordance with local characteristics. For example, transmission parameter commands are received such that the reduced mode of operation is used and to specify the characteristics to be used in the mode of operation. However, the transmission controller 115 can switch between the first and second operating modes based on local characteristics so that no specific transmission parameter command needs to be received. Thus, the transmission parameter command enables the reduced mode to set the transmission characteristics applied so that the remote unit 101 uses less resources that require transmission parameters when feasible.

As an example, the transmission controller 115 includes a sound detection element that detects which sound the microphone acquires or whether the sound environment of the remote unit 101 is quiet. In some such embodiments, the transmission controller 115 may operate in full environmental listening when sound is detected and in a reduced mode of operation when relatively static is detected. This allows the remote unit 101 to adapt to the local sound environment automatically and quickly and as a result can significantly reduce power consumption, heating, and interference without unacceptably degraded environmental listening services.

In some embodiments, the sound detection element may be configured or include a voice detector that generates voice detection characteristics. The voice detection characteristic indicates whether the microphone acquires speech, and if so, the transmission controller enters a full environmental listening mode of operation and otherwise enters a reduced mode of operation.

Possible algorithms for sound detection elements can simply determine the (average) sound level. For example, the signal amplified from the microphone is filtered by a suitable filter. This filtered signal is compared with a predetermined volume level and if it is exceeded for a predetermined duration, the transmission controller 115 enters a full environmental listening mode. Equally, if the filtered signal falls below a predetermined threshold for a predetermined duration, the transmission controller 115 causes the remote unit 101 to enter a reduced mode of operation.

In some embodiments, the characteristics and parameters of the mode of operation algorithm used by the transmission controller may be determined in accordance with the transmission parameter commands received from the control unit 107. For example, the duration of the volume threshold that must be crossed before the mode transfer is performed can be set by a transmission parameter command from the control unit 107.

In some embodiments, the monitored communication unit (such as remote unit 101) may send operating parameter information to the monitoring communication unit (such as control unit 107).

For example, instead of transmitting environmental listening data, the monitored communication unit may transmit parameter information when in a reduced operational mode rather than in a full environmental listening mode of operation. The operating parameter information allows the monitoring communication unit to provide additional information so that the operation of the monitored communication unit can be more precisely controlled to suit the current state. Thus, in some embodiments environment listening controller 119 and / or command controller 121 use operating parameter information to determine a desired transmission parameter and / or transmission parameter command.

The operating parameter information can be, for example, information regarding the characteristics of the monitored communication unit or the environmental listening performance. In particular, the operating parameter information includes one or more parameters to be described later.

It is desirable to reduce the heating of the monitored communication unit to reduce the likelihood of environmental listening behavior being detected. For example, a temperature increase of about 3-4 degrees can be tolerated, but above that is undesirable. Thus, the monitored communication unit can transmit operating parameter information including an operating temperature indication of the monitored communication unit. When this operating temperature is compared with a predetermined value and increased below this value, the monitoring communication unit drives the reduced environmental listening operation as described above.

As mentioned above, the power consumption of the monitored communication unit can be reduced by the monitoring communication unit controlling one or more transmission parameters of the monitored communication unit. However, the advantages and risks of this operation depend on the power resources available at the monitored communication unit.

For example, if the monitored communication unit is connected to an external power source, such as a charger or main supply adapter, the monitored communication unit may have sufficient power resources, and it is not important to change the transmission parameters to obtain power reduction. Thus, the operating parameter information includes an external power connection indication for the monitored communication unit. The external power connection indication particularly reflects whether the monitored communication unit is connected to an external power source. If the monitored communication unit is connected to an external power source, the monitoring communication unit causes the monitoring communication unit to continue a full environmental listening operation, while the monitored communication unit performs a reduced environmental listening operation if the monitored communication unit depends only on the internal power resource (battery). Use at least partially.

In addition, the operating parameter information may additionally or alternatively include a battery charge indication regarding the monitored communication unit. The battery charge indication in particular indicates the remaining charge of the battery. For example, the estimated remaining battery life or charge percentage can be sent to the monitoring communication unit. The monitoring communication unit can use this information to control the environment listening operation. For example, high-quality environmental listening associated with high power consumption can be used when the battery is still high, while progressively greater power consumption reductions are introduced as battery charge is reduced.

Preferred transmission parameters may depend on the operating mode of the monitored communication unit and thus the operating parameter information includes an operating mode indication regarding the monitored communication unit. The mode of operation is used by the monitoring communication unit to determine the appropriate transmission parameter command.

For example, in a TETRA communication system, environmental listening is performed even if the monitored communication unit is powered off by the user. Preferred transmission parameters depend on whether or not the monitored communication unit is powered up and thus an on / off indication is included in the operating parameter information sent to the monitoring communication unit.

The operating parameter information is transmitted at the appropriate time. In some embodiments, operating parameter information may be transmitted by the monitored communication unit without interaction of the monitoring communication unit. However, in another embodiment, the operating parameter information is additionally or alternatively transmitted in response to a request from the monitoring communication unit. Thus, the monitoring communication unit can send an operation parameter information request message to the monitored communication unit. Upon receiving this request message, the monitored communication unit accordingly sends operating parameter information to the monitoring communication unit. This allows the monitoring communication unit to determine when new information is needed and to only carry out transmission of operating parameter information when needed or desired.

Hereinafter, an embodiment of the present invention suitable for TETRA cellular communication system will be described in more detail. In an embodiment, the environment listening operation is controlled by various message transmissions between the monitored communication unit and the monitoring communication unit.

According to this example, the TETRA standard is improved so that the monitoring communication unit changes the transmission parameters, so in situations where high quality environmental listening is not necessary, the monitoring communication unit reduces the overall transmission time and / or transmission power level.

In this embodiment, the dedicated environment listen message is exchanged in a packet data unit (PDU) between the monitored communication unit and the monitored communication unit to control the environment listen transmission.

PDUs are used as follows:

Issued by the monitoring communication unit to the monitored communication unit to configure the CTXQ request PDU call transmission method.

● CTXQ Response PDU Issued by the communication unit monitored by the monitoring communication unit in accordance with the CTXQ request PDU. This response will indicate whether the configuration was successful.

● CTXQ Question Issued by the monitoring communication unit to the monitored communication unit to request PDU operating parameter information.

● CTXQ indication PDU Issued by the communication unit monitored by the monitoring communication unit according to the CTXQ question PDU. The CTXQ indication PDU contains operating parameter information and may be sent without having to receive the CTXQ question PDU in place of the traffic data.

The transmission parameter command will be sent in the CTXQ Request PDU and the CTXQ Question PDU and will contain the following parameters:

● Skip Transmit (in Transmit (TX) frame):

Command a monitored communication unit how many time slots should be skipped

● Transmit power change:

Command a monitored communication unit for increase or decrease in transmit power

● Call Inactivity Timer (in multi-frame):

Indicates the interval at which the monitored communication unit is not transmitting voice that must wait before activating the reduced environmental listening mode.

The PDU may specifically include the following data fields:

2 shows a signal flow diagram according to an embodiment of the invention. This signal flow diagram illustrates an example of a PDU message exchange performed when promoting and supporting a reduced environmental listening mode.

If the monitoring communication unit determines that there is currently no voice activity around the remote unit (or environmental listening is not critical for some other reason), then the CTXQ request PDU 201 is sent to the monitored communication unit. For example, a CTXQ request PDU contains the following data to be sent:

When the monitored communication unit receives this message, the reduced environmental listening mode operation with the specified parameters is initiated. The CTXQ response PDU 203 is then sent to the monitoring communication unit to confirm successful reception of the data. In addition, operating parameter information is included in this message. A CTXQ Response PDU with the following data may be sent, for example:

Then, the monitored communication unit performs sound detection, and if no sound is detected for a duration corresponding to the call inactivity value, the monitored communication unit enters the reduced transmission mode. In this mode, the monitored communication unit will send the CTXQ indication PDU 205 either at periodic intervals defined by the TX skip value or upon receipt of the CTXQ question PDU 207.

If the monitored communication unit detects sound or voice activity, it will exit the reduced transmission mode and return to normal transmission operation.

The monitoring communication unit may further change the transmission parameters regarding the monitored communication unit during normal operation or reduced environmental listening operation by further sending a CTXQ request PDU. In particular, the data from the latter CTXQ request PDU may overwrite the data received in the previous CTXQ request PDU.

The invention can be implemented in any suitable form including hardware, software, firmware or a combination thereof. However, it is preferred that the present invention be implemented at least partially as computer software running on one or more data processors and / or digital signal processors. The elements and configurations of embodiments of the present invention may be implemented physically, functionally and logically in any suitable manner. In addition, the functionality may be implemented as a single unit, multiple units, or as part of another functional unit. As such, the invention may be implemented between a single unit or other units and processors that are physically and functionally distributed.

Although the present invention has been described in connection with preferred embodiments, it is not intended to be limited to the specific form set forth herein. Rather, the scope of the invention is limited only by the appended claims. In the claims, the word comprising does not exclude the presence of other configurations and steps. In addition, although individually listed, multiple means, configurations or method steps may be implemented by, for example, a single unit or processor. Additionally, although individual features may be included in other claims, they may possibly be combined advantageously, and what is included in the other claims does not imply that the combination of features is infeasible and / or not advantageous. Moreover, a single expression does not exclude many. Thus, expressions such as "one", "first", "second", and the like do not exclude a plurality.

Claims (10)

A system for operating a monitoring communication unit and an ambient listening mode associated with a monitored communication unit in a wireless communication system, comprising: A monitoring communication unit, comprising: means for receiving environment listening mode transmissions from the monitored communication unit; And means for sending at least one transmission parameter command to the monitored communication unit; And A monitored communication unit, comprising: means for sending the environment listening mode transmissions to the monitoring communication unit; Means for receiving the at least one transmission parameter command from the monitoring communication unit; And means for setting at least one transmission parameter of said environment listening mode transmissions in response to said at least one transmission parameter command. The method of claim 1, And said at least one transmission parameter comprises at least one of a) a continuous parameter of said environmental listening mode transmissions and b) a transmission power parameter. The method of claim 1, And the means for transmitting the environmental listen mode transmissions are operable to transmit discontinuously and the at least one transmission parameter comprises a time characteristic of the at least one discontinuous transmission. The method of claim 3, wherein The time characteristic comprises at least one of a) a duration of the at least one discontinuous transmission and b) an interval between discontinuous transmissions. The method of claim 1, The monitored communication unit comprises means for sending operating parameter information to the monitoring communication unit. The method of claim 5, wherein The operating parameter information includes a) an operating temperature indication of the monitored communication unit, b) a battery charging indication of the monitored communication unit, c) an external power connection indication for the monitored communication unit, and d) the monitored communication. And at least one of an operation mode indication for the unit. The method of claim 1, The monitored communication unit is operable in a first mode of operation and a second mode of operation and the at least one transmission parameter is applied to transmissions in the second mode of operation other than the first mode of operation. system. The method of claim 7, wherein The monitored communication unit comprises means for switching between the first mode of operation and the second mode of operation in response to a monitored environmental sound characteristic. The method of claim 8, Wherein the monitored environmental sound characteristic is a voice detection characteristic. The method of claim 7, wherein The first mode of operation is a full monitoring operating mode and the second mode of operation is a reduced monitoring mode.

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