KR101539918B1 - Femtocell access point device for sleep mode operation, and method thereof - Google Patents

Abstract

The present invention relates to a femtocell AP device for controlling power transmission of a femtocell, and a method of driving the femtocell AP device. The femtocell AP device minimizes interference between a femtocell and a macrocell by controlling power in a normal mode and a sleep mode according to traffic in a femtocell coverage To a femtocell AP device for sleep mode operation, which reduces unnecessary femtocell power consumption, and a driving method thereof.
According to an aspect of the present invention, A femtocell service unit; A core network transmission / reception unit; Core network service unit; A power measuring unit; A judgment table; A threshold data memory; And a time data memory. The femtocell AP device includes a femtocell AP device for controlling power of a femtocell transmission using power received from peripheral cells and a reverse signal transmitted from a user terminal to a femtocell AP device, .

Description

[0001] The present invention relates to a femtocell AP device for sleep mode operation and a femtocell AP device for sleep mode operation,

The present invention relates to a femtocell AP device for controlling power transmission of a femtocell, and a method of driving the femtocell AP device. The femtocell AP device minimizes interference between a femtocell and a macrocell by controlling power in a normal mode and a sleep mode according to traffic in a femtocell coverage To a femtocell AP device for sleep mode operation, which reduces unnecessary femtocell power consumption, and a driving method thereof.

A femtocell is an ultra-small base station providing mobile communication services targeting an area much smaller than a conventional mobile communication service radius. The femtocell is mainly installed in a shaded area where the propagation of a macrocell is deteriorated, such as in a home or a building, to guarantee the quality of a mobile communication service, or a hot spot, To reduce the traffic of existing macro cells. In addition, since femtocell uses a general Internet line for connection with a core network, installation cost and maintenance cost are low, and an area where an Internet line is installed can be installed anywhere, which is advantageous in mobility. However, due to the introduction of a large number of femtocells in the mobile communication network, cell division increases and frequent mutual interference problems occur between the femtocell and the macrocell. Accordingly, various attempts have been made to reduce such interference, and as a result, techniques for optimizing the transmit power of the femtocell according to the surrounding conditions have been developed.

As a background to the present invention, a power control system and its control method for energy saving of a femtocell in conjunction with a mobile communication cell of Korean Patent Laid-Open Publication No. 10-2011-0136424 shown in FIG. 1, There is a femtocell control device included in a control system and a control method thereof. This technology most frequently handles handover of communication through at least one radio access device included in a group of femtocells among the base stations included in a predetermined mobile communication cell in the periphery whose femtocell control device has a wider coverage than the femtocell Selecting a base station as a master base station; The femtocell control apparatus switches to the sleep mode when the amount of communication through the wireless connection apparatus included in the group of femtocells falls below a preset value, and the power of the communication module of the wireless access apparatus included in the group of femtocells Controlling the selected master base station to transmit sleep mode switching state information to a master base station control apparatus controlling the selected master base station; When the sleep mode switching state information is received from the femtocell control apparatus, the master base station control apparatus performs load balancing with the base station included in another mobile communication cell, and communication generated in the group of femtocells is transmitted to the mobile communication cell And resetting the SON (Self-Organizing Network) to be directly handled by the included base stations.

As another background of the present invention, there is a method and apparatus for reducing power consumption of a femto base station using an ANR function in a wireless communication system of Korean Patent Laid-Open No. 10-2011-0127971 shown in FIG. The present invention relates to a wireless communication system including a plurality of femto base stations using Automatic Neighbor Relation (ANR), comprising: a receiver for receiving a signal from adjacent second femto base stations; a transmitter for transmitting a signal to second femto base stations; And a controller for controlling the femto base station to transit to an active mode when receiving a mode transition command from at least one second femto base station when operating in a sleep mode.

As another background of the present invention, there is a method and apparatus for reducing power consumption of a femto base station operating as a CSG cell in a wireless communication system of Korean Patent Laid-Open No. 10-2011-0127970 shown in FIG. This technique comprises: a location confirmation unit for confirming locations of terminals registered in a femto base station located in a macro cell; A location comparison unit for comparing an identified location of the terminals with a service coverage of the macro base station; And a control unit for instructing switching of the operation mode of the femto base station according to the result of the comparison, wherein the macro base station to which the femto base station belongs is determined whether the terminals registered in the femto base station exist in the service coverage of the macro base station The method comprising the steps of: confirming an operation mode of the femto base station when at least one of the registered terminals exists in the service coverage of the macro base station as a result of the checking; , The macro base station instructs the femto base station to switch the active mode.

KR 10-2011-0136424 A KR 10-2011-0127971 A KR 10-2011-0127970 A KR 10-0661549 B1 KR 10-0698771 B1 KR 10-1259221 B1 KR 10-1091686 B1 WO 2007127942 A2 WO 2010061628 A1 WO 2011118212 A1 WO 2010013248 A1

 TR-196 'Femto Access Point Service Data Model', Issue: 1 Amendment 1, Broadband Forum technical report, May 2011  3GPP TS 23.221 V10.0.0 Technical Specification Group Services and System Aspects; Architectural requirements, 2011-03  3GPP TS 36.300 V10.3.0 Group Radio Access Network E-UTRAN and E-UTRAN Overall description, 2011-03  3GPP TS 36.101 V12.0.0 Group Radio Access Network; Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE) radio transmission and reception, 2013-07  3GPP TS 36.211 V9.1.0 Group Radio Access Network; Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Channels and Modulation, 2010-03

The present invention provides a femtocell AP device for a sleep mode operation in which interference between a femtocell and a macro cell is minimized by controlling power of a femtocell transmission according to traffic in a femtocell coverage and unnecessary femtocell power consumption is reduced and a driving method thereof And to solve the problem.

According to an aspect of the present invention, there is provided a communication system including a controller, a transmitter and a receiver, A femtocell service unit; A core network transmission / reception unit; Core network service unit; A power measuring unit; A judgment table; A threshold data memory; And a time data memory, and a method of driving the femtocell AP device as a solution to the problem.

According to the femtocell AP device and the method of driving the femtocell AP device for operating the sleep mode of the present invention, it is possible to minimize the interference between the femtocell and the macrocell by controlling the power of the femtocell transmission according to the traffic in the femtocell coverage and to reduce unnecessary femtocell power consumption. Effect.

FIG. 1 is a circuit diagram of a power control system for energy saving of a femtocell in connection with a mobile communication cell and a configuration
FIG. 2 is another background of the present invention as a method for reducing power consumption of a femto base station using an ANR function in a wireless communication system and a configuration of a device technology
FIG. 3 is a schematic diagram of a method for reducing power consumption of a femto base station operating as a CSG cell in a wireless communication system and a configuration of an apparatus technology
4 shows an example of femtocell and macrocell configuration
5 shows an example of the femtocell detailed configuration
FIG. 6 is a flowchart illustrating a signal and information flow for searching for power received from neighboring cells in the femtocell AP device of the present invention.
7 shows a configuration of a femtocell AP device for the sleep mode operation of the present invention
FIG. 8 is a diagram illustrating a configuration for a sleep mode operation of the femtocell AP device of the present invention;
9 is an application environment model of the femtocell AP device of the present invention
10 shows an operation mode and an example of a search cycle determination table according to a neighbor cell search of the femtocell AP device of the present invention
11 is a flowchart of a method of driving a femtocell AP device for sleep mode operation of the present invention
12 is a flowchart of a method of driving an exception process for a femtocell AP device for sleep mode operation of the present invention

The following merely illustrates the principles of the invention. Accordingly, those skilled in the art will be able to devise various apparatuses which, although not explicitly described or shown herein, embody the principles of the invention and are included in the concept and scope of the invention. It is to be understood that all of the conditional terms and embodiments recited herein are expressly intended to be purely for purposes of understanding the concepts of the present invention and are not intended to be limiting to such specifically recited embodiments and conditions . It is also to be understood that the detailed description, as well as the principles, aspects and embodiments of the invention, as well as specific embodiments thereof, are intended to cover structural and functional equivalents thereof.

The above objects, features and advantages will become more apparent from the following detailed description in conjunction with the accompanying drawings. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 4 schematically illustrates an Evolved Universal Terrestrial Radio Access Network (E-UTRAN) and an LTE femtocell configuration of 3GPP as an example of a femtocell and macrocell configuration. The user mobile is a femto AP subsystem which is a home eNode subsystem (HeNS) composed of a macro-cell subsystem, which is a radio network subsystem (RNS), and a femtocell, (Evolved Packet Core) network, which is a core network, through a dual access network (FAP Subsystem), thereby providing a PSTN and an Internet service for a user terminal.

FIG. 5 shows an example of the femtocell detailed configuration. FIG. 5 shows an example of a connection configuration to a core network via a FAP (Femto Access Point). The connection structure of the drawings is a service structure through a stand-alone FAP that is served in a limited space in the home or building as a wirelessly connected FAP and an integrated FAP that provides general services. The stand-alone FAP and the integrated FAP are connected to a broadband service network, and if necessary, a stand-alone FAP is connected to a home gateway (RGW) residential gateway to a wide-area service network. The wide area service network is connected to the core network through a femto gateway (GW) for passing a large number of FAPs through a core network via a security gateway (SeGW). An auto-configuration server (ACS) is connected to the security gateway (SeGW) to manage and manage (OAM) the FAPs.

The present invention relates to a method and apparatus for receiving a reverse signal transmitted from a user terminal in a femtocell coverage to a femtocell AP device through a sniff (hereinafter referred to as a search) And a method of driving the femtocell AP device. In the present invention, the normal mode indicates a state in which the femtocell AP device transmits / receives service information. Since the femtocell AP device does not transmit service information and does not process the received signal, A state in which only a reverse signal transmitted from a user terminal to a femtocell AP device is searched is defined as a sleep mode. Therefore, the femtocell AP device for the sleep mode operation of the present invention can reduce the power consumption by performing low-power search operation without transmitting / receiving service information in a sleep mode. Further, the present invention provides a method for controlling a femtocell service quality by controlling a femtocell in a normal mode or a sleep mode by searching for a reverse signal transmitted to a femtocell AP device for a service request, A femtocell AP device and a method for driving the femtocell AP device.

Hereinafter, the configuration and operation of the present invention for controlling the normal mode and the sleep mode according to the reverse signal transmitted to the femtocell AP device will be described.

FIG. 6 shows a flow of signals and information for searching for power received from peripheral cells in a femtocell AP device for sleep mode operation of the present invention.

First, when the femtocell AP device of the present invention is operated, the femtocell AP generally sniffs neighbor cells. In the searching step, a synchronization channel (sync. Cnannel) of a neighboring macro cell or a neighboring femtocell is searched and a pilot (or reference) signal is detected, and the transmission information of the neighboring macrocell or the neighbor femtocell can be decoded. The neighboring cell search includes a configuration for deriving power from a signal received from peripheral cells and comparing the received power with a reference power, and the received power from the neighbor macrocell and the received power from the neighbor femtocell are RSRP Signal Received Power), Received Signal Code Power (RSCP), or Received Signal Strength Indicator (RSSI). Also, a plurality of received powers of RSRP, RSSI, RSCP, and RSSI may be used to derive received power from neighboring macrocells and received power from neighboring femtocells.

The basic condition for the femtocell AP device of the present invention to detect the power received from peripheral cells and to compare the received power with the reference power may be expressed by the following conditions (1) and (2).

(1) max {Pi_macro} > PTH_sniff_M

(2) max {Pj_femto} > PTH_sniff_F

The condition (1) is that when the femtocell AP device of the present invention sniffs the powers of {Pi_macro} from the i neighboring macrocells, the maximum value of the received power {Pi_macro} is detected and compared with the reference power PTH_sniff_M And there is a surrounding macrocell that is larger than the reference power PTH_sniff_M, the service area of the femtocell AP device of the present invention means that the service by the corresponding macrocell is also possible. If there is no neighboring macrocell that is larger than the reference power PTH_sniff_M, the service area of the femtocell AP device of the present invention can be determined to be only the service by the femtocell AP device because the service by the macrocell is impossible.

Here, the reference power PTH_sniff_M can be set to the magnitude of power that can be serviced by the macrocell for the user terminal Mx.

The condition (2) is that when the femtocell AP device of the present invention sniffs the powers of {Pj_femto} from the other j femtocells in the vicinity, the maximum value of the received powers {Pj_femto} is detected and compared with the reference power PTH_sniff_F And there is a surrounding femtocell that is larger than the reference power PTH_sniff_F, the service area of the femtocell AP device of the present invention means that the service by other neighboring femtocells is possible. When there is no neighbor femtocell that is larger than the reference power PTH_sniff_F, it can be determined that only the service by the femtocell AP device of the present invention can be performed because the service area of the femtocell AP device of the present invention can not be serviced by the neighboring femtocell. Here, the reference power PTH_sniff_F can be set to the magnitude of power available for the neighboring femtocell service to the user terminal Mx.

At this time, the femtocell AP device searches for a synchronization channel (sync. Cnannel) of a neighboring macro cell or a neighbor femtocell, detects a pilot (or reference) signal, and decodes transmission information of the neighboring macrocell or the neighbor femtocell to extract a femto designation factor CSG indication or a cell identifier, it is possible to distinguish whether a neighbor cell in which a signal is received is a macro cell or a femtocell. For example, in the case of the WCDMA system, the femtocell and the macrocell operate separately by separating the primary scrambling code (PSC), which is a cell division factor, and the PCI (Physical Cell Identifier) Cell classification is possible. In addition, 3GPP Rel. Since the MIM (Master Information Block) is included in the WCDMA and the CSG indication field is included in the SIB1 (System Information Block) in the case of LTE, if the femtocell is set as a CSG (Closed Subscriber Group) cell, The femtocell can be directly classified into the femtocell through the PSC or the PCI without setting the femtocell as the CSG cell.

FIG. 7 shows a configuration of a femtocell AP device for sleep mode operation of the present invention.

The femtocell AP (FAP) device of the present invention includes a controller 100,

A transmitter unit 102 for transmitting synchronization channel (sync. Cnannel) information or a pilot (or reference) signal of the neighbor macrocell or the neighbor femtocell and transmitting downlink service data to the user terminal Mx in the service area; And

Receives data from the user terminal Mx in a normal mode, receives a peripheral macrocell, a peripheral femtocell signal, and a reverse signal transmitted from the user terminal to the femtocell AP device in a sleep mode A receiver unit (104) for receiving the data;

 And a femtocell service unit 106 connected to the transmitter unit 102 and the receiver unit 104 to provide a service in the femtocell by the controller 100.

A core network transceiver 108 for connecting a femtocell AP (FAP) device to a core network via a FAP subsystem (FAP Subsystem);

And a core network service unit 110 that provides a service of the core network to the femtocell in connection with the core network transceiver 108.

The receiver unit 104 is provided as a single-band receiver unit in the case of a LTE (Long Term Evolution) system in which neighboring macrocells, peripheral femtocells, and user terminals use the same band, When a macro cell and a femtocell use different frequency bands, such as 3G or Global System for Mobile Communications (GSM), the macrocell band receiver, the femtocell, and the user terminal band receiver may be separately provided.

Further, the femtocell AP (FAP) device of the present invention has a configuration for controlling the sleep mode and the normal mode,

A power measuring unit 112 for receiving a peripheral macrocell provided from the receiving unit, a peripheral femtocell signal, and a backward signal from the user terminal and measuring reception power,

The controller 100 uses the reverse received power from the neighboring macrocells, the neighbor femtocells, and the user terminal provided from the power measuring unit 112 to determine a decision rule for controlling the sleep mode and the normal mode A table 114 (decision table);

A threshold data memory (116) for storing reference power values for received powers for controlling the sleep mode and the normal mode; And

And a time data memory 118 (Time Data Memory) for storing time information for controlling the sleep mode and the normal mode.

The reference power values stored in the threshold data memory (116) include:

A threshold power value of a neighboring macro cell capable of serving for a user terminal Mx located in a service area of a femtocell AP (FAP) device: PTH_sniff_M

A threshold power value of an adjacent femtocell capable of serving for a user terminal Mx located in a service area of a femtocell AP (FAP) device: PTH_sniff_F

- Reverse threshold power value from the user terminal Mx located in the service area of the femtocell AP (FAP) device: PTH_sleep

Are stored. In general, as examples of the reference power values, PTH_sniff_M, PTH_sniff_F, and PTH_sleep may be set to power near -95 dBm, respectively.

The time information stored in the time data memory 118 includes:

- Long cycle time when a femtocell AP (FAP) device sniffs neighboring macrocells or neighboring femtocells: Tlong

- Short cycle time in which a femtocell AP (FAP) device sniffs neighboring macrocells or neighboring femtocells: Tshort

- Retention time of the reverse signal transmitted from the user terminal to the femtocell AP device: Tduration

Are stored. The period (Tsniff_period) during which the femtocell AP (sniffer) the surrounding macrocells or neighboring femtocells detect may be defined as the sleep time in the sleep mode or the normal mode set in the femtocell AP (FAP) have. As an example of a period (Tsniff_period) during which the femtocell AP (sniffer) the surrounding macrocells or neighboring femtocells, the long cycle time Tlong is set to 6, 12, or 24 hours, as a short cycle time Tshort 10 minutes, 30 minutes, and 1 hour, respectively. Also, the retention time (Tduration) of the reverse signal transmitted from the user terminal to the femtocell AP device can be set to 10, 30, 60 seconds within 1 minute, and the time information stored in the time data memory 118 can be set It is possible to increase or decrease.

FIG. 8 illustrates a configuration for a sleep mode operation of the femtocell AP device of the present invention. In the sleep mode of the present invention, the femtocell AP device does not perform service information transmission or reception signal processing, which consumes a large amount of power, and only searches for a power received from peripheral cells and a reverse signal transmitted from the user terminal to the femtocell AP device .

To this end, the femtocell AP (FAP) device of the present invention includes a power consuming transmitter 102 in a sleep mode; A receiving unit 104; A femtocell service unit 106; The core network transmission / reception unit 108 and the core network service unit 110 are deactivated by the control unit 100. Accordingly, the femtocell AP (FAP) device of the present invention is characterized in that in a sleep mode;

Centering on the controller 100,

A power measurement unit 112 for receiving a peripheral macrocell provided from a receiver, a peripheral femtocell signal, and a backward signal from the user terminal and measuring reception power;

A decision table for storing a decision rule for the controller 100 to perform the sleep mode and the normal mode control by using the reverse received power from the peripheral macrocell, the peripheral femtocell, and the user terminal provided from the power measuring unit 112, (114) a decision table

A threshold data memory (116) for storing reference power values for received powers for controlling the sleep mode and the normal mode; And

Only a time data memory 118 (Time Data Memory) for storing time information for controlling the sleep mode and the normal mode is activated by the control unit 100. [

The femtocell AP device of the present invention as described above further includes a configuration for activating the core network transmission / reception unit 108 in the sleep mode operation by the control unit 100, Mode can be configured. In this case, when information for normal mode switching is received from the core network through the core network transmission / reception unit 108, the control unit 100 includes an exception process (i.e., an interrupt process) for switching the femtocell AP device to the normal mode Can be achieved.

FIG. 9 shows an application environment model of the femtocell AP device of the present invention. In the drawing, a hexagonal area indicates a macro cell serviced by a macro base station, and a shaded area outside the macro cell service area is shown on the right side of the figure. The area shown in a circle in the environment model of the drawing shows femtocell AP devices and their service areas, and each of the femtocell AP devices is referred to as FAP1 to FAP6, and user terminals located within the service area of each femtocell AP device are respectively referred to as M1- M6. In the drawing, FAP2 and FAP4 are adjacent femtocell devices, and FAP1, FAP3, FAP5, and FAP6 are assumed to be the femtocell AP devices of the present invention, and their operation will be described.

The femtocell AP device of the present invention determines that the user terminal Mx is located within the service area if the power PRX of the reverse signal transmitted from the user terminal Mx is greater than the threshold power value PTH_sleep during the hold time Tduration and provides the service in the normal mode. Therefore, FAP1, FAP3, FAP5, and FAP6 in FIG. 9 are all described in a state in which the user terminals M1, M3, M5, and M6 are located in the service area and both are operating in the normal mode.

- FAP1

The service area of FAP1 is overlapped with the service area of Macro BS (Macro Base Station). Therefore, in FAP1, power of neighboring macro cells larger than the threshold power value PTH_sniff_M is received. However, because the service of another adjacent femtocell is not available in the service area of FAP1, the power of the adjacent femtocell smaller than the threshold power value PTH_sniff_F is received at FAP1. In this environment, if the reverse received power from the user terminal M1 is received with a value larger than the reverse threshold power value PTH_sleep, it is determined that the user terminal exists in the service area, and FAP1 performs the service in the normal mode. If the reverse received power from the user terminal is received with a value less than the reverse threshold power value PTH_sleep, it is determined that there is no user terminal in the service area, and FAP1 is switched to the sleep mode. Since the service area of the FAP1 overlaps with the service area of the macro cell, the user terminal can receive at least the service of the macro cell. Therefore, the search period Tsniff_period of FAP1 is set to a long cycle time (Tlong).

- FAP3

The service area of FAP3 is overlapped with the service area of Macro BS (Macro Base Station) and the service area of FAP2. Therefore, in FAP3, the power of the adjacent macrocell greater than the threshold power value PTH_sniff_M and the power from the adjacent femtocell FAP2 that is larger than the threshold power value PTH_sniff_F are received. In this environment, when the reverse received power from the user terminal M3 is received with a value larger than the reverse threshold power value PTH_sleep, it is determined that the user terminal exists in the service area, and the FAP 3 performs the service in the normal mode. If the reverse received power from the user terminal is received with a value less than the reverse threshold power value PTH_sleep, it is determined that there is no user terminal in the service area, and the FAP 3 is switched to the sleep mode. Since the service area of the FAP3 overlaps with the service area of the macrocell and the adjacent femtocell FAP2, the user terminal can receive the service of the macrocell and the FAP2. Therefore, the search period Tsniff_period of FAP3 in the sleep mode is set to a long cycle time (Tlong).

- FAP5

The service area of the FAP 5 overlaps with the service area of the FAP 4 but is located outside the service area of the macro cell. Therefore, in FAP5, the power of the adjacent macrocell smaller than the threshold power value PTH_sniff_M and the power from the adjacent femtocell FAP4 that is larger than the threshold power value PTH_sniff_F are received. In this environment, when the reverse received power from the user terminal M5 is received with a value larger than the reverse threshold power value PTH_sleep, it is determined that the user terminal exists in the service area, and the FAP 5 performs the service in the normal mode. If the reverse received power from the user terminal is received with a value smaller than the reverse threshold power value PTH_sleep, it is determined that there is no user terminal in the service area, and the FAP 5 is switched to the sleep mode. Since the service area of the FAP 5 overlaps with the service area of the adjacent femtocell FAP 4, the user terminal can receive the service of the FAP 4.

In this case, when FAP4 is operated in the normal mode, there is no traffic in the FAP5 area. When the FAP5 is switched to the sleep mode and then the FAP4 is switched to the sleep mode, the coverage of FAP5 is instantaneously shaded. In this case, since the FAP 5 must be serviced immediately regardless of the traffic, the search period Tsniff_period of the FAP 5 in the sleep mode is set to the short cycle time (Tshort).

- FAP6

The service area of the FAP 6 is located outside the service area of the adjacent femtocell and macrocell. Therefore, in FAP6, the power of the adjacent macrocell smaller than the threshold power value PTH_sniff_M and the power of the adjacent femtocell smaller than the threshold power value PTH_sniff_F are received. In this environment, the FAP6 can not be switched to the sleep mode, so the normal mode service should always be provided. In addition, since the variation of adjacent femtocells and macrocells is not abrupt, the search period Tsniff_period of FAP6 is set to a long cycle time (Tlong).

FIG. 10 shows an example of an operation mode and a search cycle determination table according to a neighbor cell search of the femtocell AP device of the present invention.

7, the operation mode and the search period determination table of the present invention are transmitted to the controller 100 using the reverse received power from the peripheral macrocell, the peripheral femtocell, and the user terminal provided from the power measuring unit 112, Is stored in the judgment table 114 for storing a decision rule for controlling the sleep mode and the normal mode. At this time, the determination table 114 may include:

1 'when max {Pi_macro} < PTH_sniff_M,' 0 'when max {Pi_macro}

'0' when max {Pj_femto} <PTH_sniff_F, '1' when max {Pj_femto}

When PRX <PTH_sleep, '0', and when PRX ≥ PTH_sleep, '1' is input,

'0' if Tsniff_period is Tlong, '1' if Tsniff_period is Tshort,

0 'if the operation mode is normal, and' 1 'if the operation mode is Sleep. Referring to FIG. 10, in order to more clearly illustrate the operation of the present invention, the reverse reception power, the reference power, the search period Tsniff_period, and the mode of operation from the neighboring macrocell, the neighbor femtocell, and the user terminal are described do.

When the service area of the femtocell AP device of the present invention is located outside the service area of the adjacent femtocell and macrocell and the power of the adjacent macrocell smaller than the threshold power value PTH_sniff_M and the power of the adjacent femtocell smaller than the threshold power value PTH_sniff_F are received, The femtocell AP device always operates in a normal mode (Normal (A)). Also, since the variation of adjacent femtocells and macrocells is not abrupt, the search cycle Tsniff_period is set to a long cycle time (Tlong).

Further, when the femtocell AP device of the present invention receives the reverse received power PRX from the user terminal with a value larger than the reverse threshold power value PTH_sleep, it determines that the user terminal exists in the service area and performs the service in the normal mode.

In the environment where the service area of the femtocell AP device of the present invention is positioned within the service area of the adjacent femtocell or macrocell and the power of the neighboring macrocell greater than the threshold power value PTH_sniff_M or the power of the adjacent femtocell greater than the threshold power value PTH_sniff_F is received, If the reverse received power from the terminal is received with a value smaller than the reverse threshold power value PTH_sleep, the femtocell AP device of the present invention is switched to the sleep mode.

At this time, if the service area of the femtocell AP device of the present invention is located within the service area of the macrocell, the search period Tsniff_period is set to a long cycle time (Tlong), and if the service area of the femtocell AP device of the present invention is located within the service area of the adjacent femtocell And the search cycle Tsniff_period is set to a short cycle time (Tshort) when it is located outside the service area of the macro cell.

The femtocell AP device for the sleep mode operation of the present invention further includes a configuration for activating the core network transmission / reception unit 108 by the control unit 100 in the sleep mode operation as described in FIG. 8, It is also possible to configure to be able to switch from the core network to the required normal mode, including in an emergency. In this case, when the information for normal mode switching is received from the core network through the core network transmission / reception unit 108, the control unit 100 performs an exceptional normal mode operation for switching the femtocell AP device to the normal mode . The SIB 10 and the SIB 11 of the LTE system are connected to the Earthquake and Tsunami Warning System (ETWS), and the SIB 12 is a commercial mobile alerting system (CMAS)). Therefore, when the SIB 10, the SIB 11, and the SIB 12 are received from the core network, the femtocell AP device of the present invention can be switched to the normal mode by performing an exception process such as an interruption .

FIG. 11 shows a flowchart of a method of driving a femtocell AP device for sleep mode operation of the present invention.

First, when the power of the femtocell AP device for sleep mode operation of the present invention is supplied and operation starts (SlOO);

- The femtocell AP device sniffs neighboring cells to derive power, detects the maximum of the surrounding macrocell received power {Pi_macro}, compares it with the reference power PTH_sniff_M of the macrocell, Detecting a maximum value among the femtocell received power {Pj_femto} and comparing the detected maximum value with a reference power PTH_sniff_F of the femtocell (Sl 10);

In the above step, if the macrocell receive power is greater than the reference power PTH_sniff_M, the search cycle Tsniff_period is set to the long cycle time Tlong, and if there is only the femtocell receive power greater than the reference power PTH_sniff_F, the search cycle Tsniff_period is short And a parameter setting step (S120) of setting a cycle time (Tshort)

- a reverse power search step (S130) of deriving a received power PRX of a reverse signal transmitted from the user terminal to the femtocell AP device

A step (S140) of determining whether a reception power PRX of a reverse signal transmitted from a user terminal to the femtocell AP device is smaller than a reverse threshold power value PTH_sleep during a maintenance time Tduration,

A step (S150) of switching to a sleep mode operation when the received power PRX is maintained at a value smaller than the inverse threshold power value PTH_sleep during the holding time Tduration in the comparison determination step (S140) of the reception power PRX and the reverse threshold power value PTH_sleep;

If the received power PRX is greater than the inverse threshold power value PTH_sleep during the hold time Tduration in the comparison determination step S140 of the received power PRX and the reverse threshold power value PTH_sleep, the normal mode (S160); and,

- determining whether the set search period Tsniff_period is terminated (S170);

If the set search period Tsniff_period is not terminated, the mobile station repeats the reverse power search step (S130) of deriving the received power PRX of the reverse signal transmitted from the user terminal to the femtocell AP device,

- If the set search period Tsniff_period has expired, the femtocell AP device sniffs neighbor cells to derive power and compare it with the reference powers (S110).

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- The femtocell AP device sniffs neighboring cells to derive power, detects the maximum of the neighboring macrocell received power {Pi_macro}, compares it with the reference power PTH_sniff_M of the macrocell, In a step S110 of detecting a maximum value among the femtocell received power {Pj_femto} of the femtocell and comparing it with the reference power PTH_sniff_F of the femtocell,

A parameter setting step (S180) of setting the search cycle Tsniff_period to a long cycle time (Tlong) when the macrocell receive power larger than the reference power PTH_sniff_M and the femtocell receive power larger than the reference power PTH_sniff_F are not all performed,

- operating the femtocell AP device in the normal mode (S190);

(S200) of determining whether or not the set search period Tsniff_period has ended,

If the set search period Tsniff_period has not been terminated, the femtocell AP device is operated again from the step of operating in the normal mode (S190)

If the set search period Tsniff_period is terminated, the femtocell AP device sniffs neighbor cells to derive power and compares it with reference powers (step S110).

FIG. 12 shows a flowchart of a method of driving exception processing for a femtocell AP device for sleep mode operation of the present invention. This case can be applied when information for normal mode switching (SIB 10, SIB 11, SIB 12 in the case of LTE) is received from the core network as described above.

First, when the interrupt routine of the femtocell AP device starts from the core network (S300)

The femtocell AP device determines whether the current operation mode is the normal mode (S310)

In operation 3210, when the femtocell AP device is in the sleep mode, the normal mode is switched to the normal mode. In operation 3220,

- checking whether information for releasing the exception processing drive from the core network to the femtocell AP device is transmitted (S330)

- If information for releasing the exception handling drive is not transmitted, it is repeatedly checked whether information for releasing the exception handling drive is transmitted (S330)

- The interrupt routine is terminated when information to release the exception handling drive is sent.

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In operation S310, if the femtocell AP device is in the normal mode, it is checked whether information for releasing the exception processing from the core network to the femtocell AP device is transmitted in operation S330. .

According to the femtocell AP device and the method of driving the femtocell AP device for operating the sleep mode of the present invention as described above, interference between the femtocell and the macrocell can be minimized by controlling the power of the femtocell transmission according to the traffic in the femtocell coverage and unnecessary femtocell consumption There is a feature to save power.

Although the femtocell AP device and the driving method thereof for the sleep mode operation of the present invention have been described with reference to the limited embodiments and drawings, the present invention is not limited thereto, It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the appended claims and their equivalents.

100: controller 102: transmitter unit
104: Receiver unit 106: Femtocell service unit
108: Core Network Transceiver
110: core network service unit 112: power measurement unit
114: decision table
116: threshold data memory
118: time data memory

Claims (14)

There is provided a femtocell AP device for minimizing interference between a femtocell and a macro cell by controlling power of a femtocell transmission according to traffic in a femtocell coverage and for reducing sleep of unnecessary femtocell power consumption,
A controller 100,
A transmitter unit 102 for transmitting synchronization channel (sync. Cnannel) information or a pilot (or reference) signal of the neighbor macrocell or the neighbor femtocell and transmitting downlink service data to the user terminal Mx in the service area; And
Receives data from the user terminal Mx in a normal mode, receives a peripheral macrocell, a peripheral femtocell signal, and a reverse signal transmitted from the user terminal to the femtocell AP device in a sleep mode A receiver unit (104) for receiving the data;
A femtocell service unit 106 connected to the transmitter unit 102 and the receiver unit 104 to provide a service in the femtocell by the controller 100;
A core network transceiver 108 for connecting a femtocell AP (FAP) device to a core network via a FAP Subsystem (FAP Subsystem);
A core network service unit 110 connected to the core network transceiver 108 to provide a service of the core network to the femtocell;
A power measurement unit 112 for receiving a peripheral macrocell provided from the reception unit 104, a peripheral femtocell signal, and a backward signal from the user terminal and measuring reception power;
The controller 100 uses the reverse received power from the neighboring macrocells, the neighbor femtocells, and the user terminal provided from the power measuring unit 112 to determine a decision rule for controlling the sleep mode and the normal mode A table 114 (decision table);
A threshold data memory (116) for storing reference power values for received powers for controlling the sleep mode and the normal mode; And
And a time data memory (118: Time Data Memory) for storing the time information for controlling the sleep mode and the normal mode. The femtocell AP device
The apparatus of claim 1, wherein the receiver unit (104)
In case of a Macro Base Station, a neighboring femtocell, and a user terminal in an LTE (Long Term Evolution) system using the same band, a single band receiver is provided.
In a case where a macro cell and a femtocell use different frequency bands, such as 3G or Global System for Mobile Communications (GSM), a macro cell band receiving unit, a femtocell, and a user terminal band receiving unit are separately provided. Femtocell AP device
The apparatus of claim 1, wherein the threshold data memory (116)
A threshold power value of a neighboring macro cell capable of serving for a user terminal Mx located in a service area of a femtocell AP (FAP) device: PTH_sniff_M
A threshold power value of an adjacent femtocell capable of serving for a user terminal Mx located in a service area of a femtocell AP (FAP) device: PTH_sniff_F
- a reference power value including a reverse threshold power value (PTH_sleep) from a user terminal (Mx) located in a service area of a femtocell AP (FAP) device is stored and included in the femtocell AP device
The apparatus of claim 1, wherein the time data memory (118)
- Long cycle time when a femtocell AP (FAP) device sniffs neighboring macrocells or neighboring femtocells: Tlong
- Short cycle time in which a femtocell AP (FAP) device sniffs neighboring macrocells or neighboring femtocells: Tshort
And a retention time of the reverse signal transmitted from the user terminal to the femtocell AP device: Tdatures are stored in the femtocell AP device.
2. The femtocell AP device as claimed in claim 1,
In the sleep mode,
A controller 100; A power measuring unit 112; A determination table 114 and a threshold data memory 116; And a time data memory (Time Data Memory) (118) are activated by the controller (100). The femtocell AP device
The method of claim 5, wherein the femtocell AP device for sleep mode operation comprises:
In the sleep mode,
When the controller 100 activates the core network transmitting / receiving unit 108 and receives information for normal mode switching from the core network through the core network transmitting / receiving unit 108, the controller 100 transmits the femtocell AP device to the normal mode To the femtocell AP device for sleep mode operation
2. The femtocell AP device as claimed in claim 1,
When the service area of the femtocell AP device is located outside the service area of the adjacent femtocell and macrocell and the power of the neighboring macrocell smaller than the threshold power value PTH_sniff_M and the power of the adjacent femtocell smaller than the threshold power value PTH_sniff_F are received, Wherein the femtocell AP device is configured to operate normally in normal mode (Normal (A)), and the search period Tsniff_period is set to be a long period time (Tlong)
2. The femtocell AP device as claimed in claim 1,
When the reverse received power PRX from the user terminal is received with a value greater than the reverse threshold power value PTH_sleep, it is determined that the user terminal exists in the service area and is set to the normal mode.
2. The femtocell AP device as claimed in claim 1,
In the environment where the service area of the femtocell AP device is positioned within the service area of the adjacent femtocell or macrocell and the power of the adjacent macrocell greater than the threshold power value PTH_sniff_M or the power of the adjacent femtocell greater than the threshold power value PTH_sniff_F is received, When the femtocell AP device is received with a value smaller than the reverse threshold power value PTH_sleep, the femtocell AP device is switched to the sleep mode.
10. The femtocell AP device for sleep mode operation according to claim 9,
When the service area of the femtocell AP device is located within the service area of the macrocell, the search cycle Tsniff_period is set to a long cycle time (Tlong)
Wherein the femtocell AP device is configured to set a search cycle Tsniff_period to a short cycle time (Tshort) when the service area of the femtocell AP device is located within a service area of an adjacent femtocell and is located outside a service area of a macrocell. device
There is provided a method of operating a femtocell AP device for minimizing interference between a femtocell and a macro cell by controlling power of femtocell transmission according to traffic within a femtocell coverage, and for reducing a femtocell power consumption unnecessarily,
When the femtocell AP device is powered on and starts operating (SlOO);
- The femtocell AP device sniffs neighboring cells to derive power, detects the maximum of the surrounding macrocell received power {Pi_macro}, compares it with the reference power PTH_sniff_M of the macrocell, Detecting a maximum value among the femtocell received power {Pj_femto} and comparing the detected maximum value with a reference power PTH_sniff_F of the femtocell (Sl 10);
In the case where there is macrocell receive power greater than the reference power PTH_sniff_M in the step S110, the search cycle Tsniff_period is set to the long cycle time Tlong, and when there is only the femtocell receive power greater than the reference power PTH_sniff_F, A parameter setting step (S120) of setting Tsniff_period to a short cycle time (Tshort)
- a reverse power search step (S130) of deriving a received power PRX of a reverse signal transmitted from the user terminal to the femtocell AP device
A step (S140) of determining whether a reception power PRX of a reverse signal transmitted from a user terminal to the femtocell AP device is smaller than a reverse threshold power value PTH_sleep during a maintenance time Tduration,
A step (S150) of switching to a sleep mode operation when the received power PRX is maintained at a value smaller than the inverse threshold power value PTH_sleep during the holding time Tduration in the comparison determination step (S140) of the reception power PRX and the reverse threshold power value PTH_sleep;
If the received power PRX is greater than the inverse threshold power value PTH_sleep during the hold time Tduration in the comparison determination step S140 of the received power PRX and the reverse threshold power value PTH_sleep, the normal mode (S160); and,
- determining whether the set search period Tsniff_period is terminated (S170);
If the set search period Tsniff_period is not terminated, the mobile station repeats the reverse power search step (S130) of deriving the received power PRX of the reverse signal transmitted from the user terminal to the femtocell AP device,
[0040] - If the set search period Tsniff_period is terminated, the femtocell AP device sniffs neighbor cells to derive power and compares it with reference powers (S110). How to operate a femtocell AP device for sleep mode operation
12. The femtocell AP device of claim 11, wherein the femtocell AP device sniffs neighboring cells to derive power, detects a maximum value of neighboring macrocell received powers {Pi_macro}, and outputs a reference power PTH_sniff_M of the macrocell In step S110, a maximum value of the neighboring femtocell received power {Pj_femto} is detected and compared with the reference power PTH_sniff_F of the femtocell,

A parameter setting step (S180) of setting the search cycle Tsniff_period to a long cycle time (Tlong) when the macrocell receive power greater than the reference power PTH_sniff_M and the femtocell receive power greater than the reference power PTH_sniff_F are not all set,
- operating the femtocell AP device in a normal mode (S190);
(S200) of determining whether or not the set search period Tsniff_period has ended,
If the set search period Tsniff_period has not been terminated, the femtocell AP device is operated again from the step of operating in the normal mode (S190)
[0040] - If the set search period Tsniff_period is terminated, the femtocell AP device sniffs neighbor cells to derive power and compares it with reference powers (S110). How to operate a femtocell AP device for sleep mode operation
There is provided a method of operating a femtocell AP device for minimizing interference between a femtocell and a macro cell by controlling power of femtocell transmission according to traffic within a femtocell coverage, and for reducing a femtocell power consumption unnecessarily,

An exceptional normal mode operation for switching the femtocell AP device to the normal mode when information for normal mode switching is received from the core network;

- If the interrupt routine of the femtocell AP device starts by information transmitted from the core network (S300)
The femtocell AP device determines whether the current operation mode is the normal mode (S310)
In operation S310, when the femtocell AP device is in the sleep mode, the normal mode is switched to the normal mode. In operation S320,
- checking whether information for releasing the exception processing drive from the core network to the femtocell AP device is transmitted (S330)
- If information for releasing the exception handling drive is not transmitted, it is repeatedly checked whether information for releasing the exception handling drive is transmitted (S330)
And terminating the interrupt routine when information for releasing the exception handling drive is transmitted. The femtocell AP device according to claim 1,
14. The method of claim 13, wherein in the determining whether the mode is the normal mode (S310)
And a step (S330) of checking if information for releasing the exception processing drive is transmitted from the core network to the femtocell AP device if the femtocell AP device is in the normal mode. How to operate a femtocell AP device

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