KR20110115883A - Method and apparatus for location based service in wireless communication system - Google Patents

Abstract

In a wireless communication system, a method of operating a base station for location based service (LBS) includes a process of allocating a plurality of devices by reusing a synchronization sequence to distinguish a plurality of devices in the same service area. During the LBS zone, a process of transmitting a reference signal to the terminal through the plurality of devices in a plurality of LBS zone, receiving control information for the LBS service from the terminal, and based on the control information, And determining the location of the terminal.

Description

Method and apparatus for location based service in wireless communication system {METHOD AND APPARATUS FOR LOCATION BASED SERVICE IN WIRELESS COMMUNICATION SYSTEM}

The present invention relates to location-based services in a wireless communication system, and more particularly, to a method and apparatus for performing location-based services using a preamble in an IEEE 802.16m system.

Currently, the mobile communication system has been developed in the form of providing various services such as broadcasting, multimedia video, and multimedia messages from the existing voice communication. These next-generation communication systems include the Institute of Electrical and Electronics Engineers (IEEE) 802.16e system currently in use, the 3GPP Long Term Evolution (LTE), IEEE 802.20 Ultra Mobile Broadband (UMB), and IEEE 802.16m system, which are currently being standardized. Etc.

In the mobile communication system, due to topographical requirements that cause attenuation or distribution of signals in a cell, distance between the terminal and the base station, or movement of the terminal, the channel state is poor, and thus the communication between the terminal and the base station may not be performed smoothly. For example, even within a service area of a macro base station, a radio wave shadow area may be formed in an enclosed building. If the terminal is located in the radio shadow area, the base station cannot perform smooth communication with the terminal.

In order to provide a location based service (hereinafter referred to as "LBS"), smooth transmission of a reference signal (RS) should be assumed, but may be restricted in the above case.

In general, a technique for estimating the location of a terminal may be classified into a network-based technology and a terminal-based technology. Representative terminal-based technology is a technique using a Global Positioning System (GPS), which provides a very high accuracy, but there is a problem that the accuracy is inferior or does not work in urban areas or indoors. The network-based technology is a method of estimating the position of a terminal using a location of a base station and a delay time of a signal between a terminal and a base station or an incident angle of a signal using a wireless communication network. The network-based technology may be classified into a technology using a downlink and a technology using an uplink.

Conventionally, in the LBS based on the network-based technology, the terminal receives at least three reference signals (RS) from the base station, the terminal determines the transmission time and arrival time of each of the reference signals received from the three base stations After that, each distance between the terminal and the three base stations is estimated and the result is transmitted to the serving base station. The serving base station estimates the position of the terminal using the distance between the terminal and the three base stations.

Meanwhile, in a next generation mobile communication system, a distributed base station architecture separates RF transceivers from a base station so that the antennas operate with minimal transmission power loss. Relocate the RF transceivers near the antennas connected to the antenna. That is, in a distributed base station architecture, a plurality of RF transceivers (hereinafter referred to as Remote Radio Heads (RRHs)) are distributed in one cell, and there is a considerable distance between the base station and the plurality of RRHs and is connected by an optical cable.

Conventionally, in an environment such as a distributed base station architecture or a repeater-based wireless communication system in which a plurality of RRHs are distributed in one cell, when a base station transmits a reference signal (RS) for an LBS, a plurality of RRHs or a plurality of repeaters may be used. Is sent.

However, when the terminal receives a reference signal for the LBS from a plurality of RRH or a plurality of repeaters, it is not possible to distinguish which RRH or which repeater the reference signal for the LBS is transmitted from the correct base station and the terminal between the correct The distance cannot be measured.

Accordingly, there is a need for a method and apparatus for performing accurate LBS in a wireless communication system in which a plurality of repeaters or a plurality of RRHs exist.

An object of the present invention is to provide a method and apparatus for location-based services in a wireless communication system.

Another object of the present invention is to provide a method and apparatus for performing location based service by reusing a preamble in a wireless communication system using a plurality of repeaters and a plurality of remote radio heads or RF remote heads.

According to a first aspect of the present invention for achieving the above object, in a method of operating a base station for location based service (LBS) in a wireless communication system, to distinguish a plurality of devices in the same service area Reusing a synchronization sequence, allocating to the plurality of devices, transmitting a reference signal to the terminal through the plurality of devices in the plurality of LBS zone during the LBS zone, and the LBS service from the terminal Receiving the control information for, and based on the control information, characterized in that it comprises the step of determining the location of the terminal.

According to a second aspect of the present invention for achieving the above object, a method for operating a terminal for a location based service (LBS) in a wireless communication system, during the LBS zone, a reference signal in a plurality of LBS zones Receiving at least one of a receiving entity, determining a transmitting entity transmitting the reference signal from the reference signal, transmitting entity information transmitting the determined reference signal and arrival time information of the reference signal. The reference signal is characterized in that the synchronization sequence is reused and transmitted through the plurality of devices to distinguish a plurality of devices in the same service area.

According to a third aspect of the present invention for achieving the above objects, in a base station apparatus for location based service (LBS) in a wireless communication system, to distinguish a plurality of devices in the same service area, LBS resource allocating unit for allocating synchronous permutation to the plurality of devices, a transmitter for transmitting a reference signal to the terminal through the plurality of devices in the plurality of LBS zones during the LBS zone, and the LBS from the terminal. And a report analyzer for receiving control information for a service, and a report analyzer for determining a location of the terminal based on the control information.

According to a fourth aspect of the present invention for achieving the above objects, a terminal device for a location based service (LBS) in a wireless communication system, during the LBS zone, a reference signal in a plurality of LBS zones At least one or more of a receiving unit for receiving, an LBS signal determining unit for determining a transmission entity that has transmitted the reference signal from the reference signal, transmission entity information for transmitting the determined reference signal, and arrival time information of the reference signal The control unit for reporting to the base station, wherein the reference signal is characterized in that the synchronization sequence is reused and transmitted through the plurality of devices in order to distinguish a plurality of devices in the same service area.

As described above, by performing the LBS service using the repeater and the RRH in the same service area, it is possible to expect the effect of improving the accuracy of the downlink network-based radio positioning by improving the reception performance for the neighboring base station signal. .

In addition, it is possible to solve the service shadow area problem by extending the transmission of the reference signal to the repeater, RRH, etc. in the same service area as well as the base station.

1 is an example of an LBS service using a downlink reference signal (RS) transmitted from a base station to a terminal based on a network-based technology according to an embodiment of the present invention;
2 is a base station in a service area of a base station including a plurality of repeaters or a plurality of RRHs according to an embodiment of the present invention;
3 is an example of a time division duplex (TDD) frame structure of an IEEE 802.16m system according to an embodiment of the present invention;
4 is a frame structure for an example of utilizing an LBS zone in an IEEE 802.16m system according to an embodiment of the present invention;
5 is an example of reusing the IEEE 802.16m SA-Preamble for the implementation of the present invention,
6 is a flowchart illustrating an operation of a terminal for an LBS service in a wireless communication system according to an embodiment of the present invention;
7 is a flowchart illustrating an operation of a terminal for an LBS service in a wireless communication system according to an embodiment of the present invention;
8 is a diagram of a base station apparatus for an LBS service in a wireless communication system according to an embodiment of the present invention;
9 is a terminal device for LBS service in a wireless communication system according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. In the following description of the present invention, detailed descriptions of related well-known functions or configurations will be omitted if it is determined that the detailed description of the present invention may unnecessarily obscure the subject matter of the present invention. Terms to be described later are terms defined in consideration of functions in the present invention, and may be changed according to intentions or customs of users or operators. Therefore, the definition should be made based on the contents throughout the specification.

Hereinafter, the present invention relates to a method and apparatus for Location Based Service (LBS) in Orthogonal Frequency Division Multiplexing (hereinafter referred to as "OFDM") based wireless communication system. Let's explain.

In particular, the present invention will be described with respect to LBS using a reference signal (reference signal: referred to as "RS" below) transmitted from the base station to the terminal based on the network-based technology in the IEEE 802.16m system.

Hereinafter, the present invention will be described based on the IEEEE.802.16m system, but can be applied to other wireless communication systems based on OFDM.

In addition, the present invention considers a wireless environment using a plurality of repeaters and a plurality of RRH (Remote Radio Head or RF Remote Head) in the service area of the base station in providing the LBS service.

FIG. 1 illustrates an example of an LBS service using a downlink reference signal (RS) transmitted from a base station to a terminal based on a network-based technology according to an embodiment of the present invention.

Referring to FIG. 1, in order for the serving base station of the terminal to measure the position of the terminal, the terminal first receives a reference signal (RS) from at least three base stations, and based on the reference signals received from the three base stations. The distance from the base station is estimated, and the result is reported to the serving base station using a conventional scanning report message. Depending on the implementation, it may be transmitted using a separate predefined control message.

Thereafter, the serving base station can find one point (that is, the position of the terminal) by measuring distances from three reference points based on distance information between the base stations and the terminal from the terminal. .

In another implementation, the distance measurement is estimated using the transmission time and arrival time of the reference signal for the LBS service. Therefore, when providing the LBS service using the downlink, neighboring base stations of the terminal transmits a reference signal and at the same time confirms the time when the reference signal was transmitted. In addition, the terminal checks the base station identifier in order to distinguish which base station the base station receives from the neighbor base stations. In general, a unique preamble is allocated to one base station identifier.

Thereafter, the terminal estimates the arrival time of the reference signal and reports the estimated transmission base station information of the reference signal and the arrival time of the reference signal to the serving base station. The serving base station determines the location of the terminal using the corresponding information reported by the terminal.

Although FIG. 1 illustrates an LBS service in a wireless environment in which a plurality of repeaters or a plurality of RRHs are not provided in a service area of one base station, base stations including a plurality of repeaters or a plurality of RRHs in a next-generation system as shown in FIG. The LBS service in the case of consisting of will be described.

2 illustrates an apparatus for LBS service in a service area of a base station including a plurality of repeaters or a plurality of RRHs according to an embodiment of the present invention.

Referring to FIG. 2 above, in a distributed base station architecture in which RF transceivers are separated from base station 200 to allow antennas to operate with minimal transmission power loss, multiple RRHs in the service area of the base station. Fields 210, 212, and 214 may be connected to the base station 200 through an optical cable, or one or more repeaters 220 and the base station 200 may be connected through a radio link to solve the region and increase coverage. have. In addition, the RRH 214 is connected to the RRH 212 through a cable, forming a tree structure. Depending on the wireless environment, RRHs 210, 212, and 214 may be connected to the base station 200 in various forms.

In general, a unique SA premable is assigned to each base station and used as a cell identifier.

Conventionally, since one unique SA premable is allocated to each base station, a plurality of repeaters and RRHs connected to the base station simply transmit the unique SA premable of the base station in the service area of the base station. Accordingly, a plurality of repeaters and RRHs geographically distributed in the same service area transmit reference signals for the same LBS service as the base station, thereby receiving reference signals for LBSs transmitted from a plurality of repeaters and RRHs from the terminal's point of view. Indistinguishable That is, the terminal may recognize that the base station transmits reference signals for the LBS service transmitted from the plurality of relays and the RRH. However, if the base station can distinguish the reference signals for the LBS transmitted from the plurality of repeaters and the RRH geographically distributed in the same service area, the base station can estimate the terminal position more accurately.

Accordingly, the present invention proposes a method of recognizing a plurality of relays and RRHs by reusing SA-Preamble or midamble consisting of subblocks. However, in addition to the method of reusing the SA-Preamble, it also includes a method of allocating different code sequences to distinguish the RS from the relay and the RRH.

In the following description, since SA-Preamble or midamble has the same characteristics as sub-blocks and similar utilization methods, it will be described based on the SA-Preamble.

3 illustrates an example of a time division duplex (TDD) frame structure of an IEEE 802.16m system according to an embodiment of the present invention.

Referring to FIG. 3, a superframe consists of four frames and one frame consists of eight subframes. Three types of subframes exist, Type 1 310 consisting of six OFDMA symbols, Type 2 consisting of seven symbols, and Type 3 300 consisting of five symbols.

All data transmission and reception is based on three subframe structures. In the 5, 10, and 20 MHz band, a CP has a cyclic prefix (CP) corresponding to 1/8 of an OFDMA symbol length and has a DL: UL ratio of 5: 3.

Here, there are various frame structures according to the band and CP length used, DL: UL ratio, and FDD / TDD, but all frame structures are made of a combination of three subframe types, and the combination varies depending on the frame structure. Can be.

4 illustrates a frame structure for an example of using an LBS zone in an IEEE 802.16m system according to an embodiment of the present invention.

Referring to FIG. 4, in an LBS zone section 400 including a plurality of superframes, a specific subframe section of a specific superframe is set as an LBS zone 404 and a LBS zone is periodically set (402). . That is, in the LBS zone section 400, a plurality of LBS zone 404 is discontinuously present.

For example, there are four frames in superframe 1, the SA (Secondary Advanced) preamble is located in the first symbol of frame 0, the superframe header is located after the SA preamble, and the PA is in the first symbol of frame 1. (Primary Advanced) The preamble is located, and the SA preamble is located in the first symbols of Frame 2 and Frame 3, respectively. Here, the SA preambles positioned in the first symbols of the frames 0, 2, and 3 may be the same or different SA preambles.

Here, the PA preamble is used for superframe synchronization during initial acquisition, and the SA preamble is used for cell indentification during fine synchronization.

In SF 0 of the eight subframes SF of the frame 1, the remaining symbols except for the PA preamble of the first symbol are used as symbols for the LBS reference signal. The symbol section for this continuous LBS reference signal is called an LBS zone. The base station transmits the LBS reference signal using a symbol in the LBS zone. The LBS zone is not used only the first subframe of the second frame in the superframe as in the embodiment, it may vary depending on the frame structure and situation. As described above, since the frame structure is different according to the variables such as bandwidth and the subframe types constituting each frame for each frame structure are different, the position in the frame of the subframe in which the LBS symbol exists, that is, the subframe The numbers can be different. The position of such a subframe may affect the position of the midamble used for MIMO in addition to the frame structure.

In other words, by using symbols in the LBS zone (hereinafter referred to as LBS symbols), a plurality of base stations transmit respective signals according to a specific pattern. The representative reference signal that can be used at this time is SA-Preamble. Of course, signals specially designed for wireless positioning may be used. For example, if there are five symbols in the LBS zone as shown in FIG. 4, LBS symbols may be allocated based on each base station number. As a representative example, when the LBS symbols in the LBS zone are 0, 1, 2, 3, and 4 in order, a method of transmitting the SA-preamble signal of the base station in the symbol period corresponding to the remainder divided by the base station number 5 is described. Can be considered Alternatively, random forms of allocation for each base station may also be considered. In this case, both the base station and the terminal should know the pattern of the random allocation in advance.

Meanwhile, in the present invention, SA-Preamble is reused based on a frequency or time axis in the LBS zone to distinguish a plurality of relays and RRHs in the same service area. A description of the SA-Preamble reuse will be described in detail with reference to FIG. 5.

In some embodiments, during the LBS zone interval 400, a plurality of LBS zones may exist in each of a plurality of consecutive superframes, or a plurality of LBS zones may exist in each of four consecutive frames within a specific superframe. have.

5 is a diagram illustrating an example of reusing an IEEE 802.16m SA-Preamble for implementation of the present invention.

Referring to FIG. 5, only one SA-Preamble sequence is allocated to one base station. The SA-Preamble includes base station number information, and thus, the terminal can estimate which base station the signal is transmitted from by receiving the SA-Preamble.

Here, the number of subcarriers allocated to the SA preamble is 144 when the FFT size is 512, 288 when the FFT size is 1024, and 576 when the FFT size is 2048. In addition, each segment uses one subcarrier set of three available carrier-sets.

On the other hand, when the FFT size is 512, the number of bits for indicating the SA preamble sequence is 288 bits, and the 288 bit SA preamble sequence is divided into eight sub-blocks, that is, A, B, C, and D. , E, F, G, and H, and the size of each subblock is 36 bits long.

Thus, there are 128 SA preamble sequences per segment, so that 8 subblocks in the SA preamble sequences have different permutations.

<Table 1> is SA preamble of segment 0, <Table 2> is SA preamble of segment 1, and <Table 3> is SA preamble of segment 3.

Idx blk A B C D E F G H 0 314C8648F 18BC23543 06361E654 27C552A2D 3A7C69A77 011B29374 277D31A46 14B032757 One 281E84559 1A0CDDF7E 2473A5D5B 2C6439AB8 1CA9304C1 0AC3BECD0 34122C7F5 25362F596 2 00538AC77 38F9CBBC6 04DBCCB40 33CDC6E42 181114BE4 0766079FA 2DD2F5450 13E0508B2 3 3BE4056D1 2C7953467 0E5F0DE66 03C9B2E7D 1857FD2E3 15A276D4F 210F282AF 27CE61310 4 3DBAAE31E 254AE8A85 168B63A64 05FDF74FB 3948B6856 33656C528 1799C9BA1 004E0B673 5 177CE8FBC 21CEE7F09 397CD6551 01D4A1A10 1730F9049 067D89EA9 3AC141077 3D7AD6888 6 3B78215A1 17F921D66 385006FDC 011432C9D 24ED16EA6 0A54922F1 02067E65D 0FEC2128D 7 01FF4E172 2A704C742 3A58705E1 3F3F66CD2 07CA4C462 1854C8AA3 03F576092 06A989824 8 1A5B7278E 1630D0D82 3001EF613 34CCF51A1 2120C250A 06893FA2D 156073692 07178CFA7 9 032E31906 2DD318EAA 1DE55B14D 0EF4B6FB3 27DED0610 1BC8440D3 0ED86BF8D 14FAFDE2C 10 174725FFD 0D2FB1732 124470F56 292D9912B 1571408A7 227197AE9 2430BC576 0B67304E0 11 1F1DCD669 293DD1701 0C34F1B84 28496EE51 3DC41327F 071C06523 28E1657B6 02588EFDA 12 22E4AA041 3810362F1 1955F1DE7 0D6D2F8BE 11F31358E 3EB27BB12 1F4E60111 119BDA927 13 14300B522 152E6D482 168DF6E43 0740B7AE0 14FE7DCDD 0FA092626 23697615A 1F1331EB8 14 12C65ED00 317643CD7 2C637A415 15E3E5185 0F5CBB9E0 23290B156 26F37EFE8 1AA174793 15 1DD6453F0 032C4BD39 082659BD5 320C5E691 224E555B2 3A9615A8D 1BED03424 28E6A9CED 16 068AE7EE9 16F724910 3803DD9BD 2A31A2FFB 010BF5237 33CB067E6 0280C28B7 184417B94 : : : : : : : : : 127 1EF89091A 11A653D2C 223FC1F42 2F7B97B31 2CA4EE011 00F68767D 10FE34682 018339212

Idx blk A B C D E F G H 0 20A601017 10D0A84DE 0A8C74995 07B9C4C42 23DB99BF9 12114A3F5 25341EDB0 362D37C00 One 1364F32EC 0C4648173 08C12DA0C 19BD8D33A 3F5F0DDA6 24F99C596 026976120 3B40418C7 2 1C6548078 0A0D98F3C 0AC496588 38CBF2572 22D7DA300 1CCEAF135 356CA0CCF 093983370 3 03A8E3621 2D2042AF5 2AB5CC93B 05A0B2E2E 0B603C09E 117AC5C94 2D9DEA5A0 0BDFF0D89 4 07C4F8A63 3E6F78118 32CCD25F2 1792A7B61 0A8659788 1F9708C04 086AF6E64 040B9CD78 5 2D7EE485A 2C3347A25 3B98E86AF 242706DC3 1CEF639AF 2E1B0D6A9 3E9F78BC1 0FB31275F 6 0307936D0 21CE15F03 392655B2D 17BE2DE53 3718F9AB8 01A986D24 077BDA4EB 1D670A3A6 7 05A10F7B7 31900ACE0 28DCA8010 2D927ABE5 370B33E05 31E57BCBE 030DC5FE1 093FDB77B 8 092C4FED1 268BF6E42 24576811F 09F2DAA7F 24EFFC8B1 21C205A90 1E7A58A84 048C453EB 9 29F162A99 1F739A8BF 09F684599 1BEC37264 38ED51986 286325300 344FC460A 3907B1161 10 0E4616304 0FABDCD08 0F6D6BE23 1B0E7FEDD 0047DE6C2 36742C0C6 2D7ABB967 10D5481DF 11 32DD51790 237D6ACFA 2F691197A 16724EA58 149143636 3810C6EE1 3A78B3FC6 1B1259333 12 1BB0FD4D3 235F10A55 1C7302A27 1148B18E5 04F25FBC8 2A0A8830C 3646DBE59 2F25F8C30 13 0FB38C45B 069DF29E9 00F93771B 3AA35746D 2CAF48FD0 0A42CDD55 19A23CE8F 26318A30F 14 365FBEDAC 27710945F 2AA367D61 05A484318 2563F27D9 2D37D5C00 287D18FBB 3ADB44805 15 3038BC77D 2A45D29EC 156173792 03EC7679E 07577E1A4 1B6A94A74 1D26E5A94 0FD878D5A 16 1F22158E4 3F02A1D37 2767EC03F 1C8CD535A 23DA2E5AB 2D5F25A59 0971AA889 3E78C1846 : : : : : : : : : 127 34F9ACB6B 384870FF1 257A863DE 34B36BA0F 3FA3D216B 27425041B 0E0DD0BAD 2E95AD35D

Idx blk A B C D E F G H 0 13F99E8EC 3CF776C2A 3300A482C 0B2BF4791 17BECDFE8 35998C6D4 05F8CB75C 259B90F0B One 116913829 05188F2A4 2DB0A8D00 2F770FE4A 185BE5E33 0F039A076 212F3F82C 116635F29 2 004EE1EC6 18EF4FDD9 26C80900E 1A63FB8A7 1DAA917D4 0E6716114 02690646D 0CC94AD36 3 06D4FF377 2716E8A54 16A1720C8 08750246F 393045CCB 1DBCCDE43 114A0CAD6 181690377 4 3DC4EF347 1F53452FC 01584B5D3 11D96034F 1FA62568E 11974FACA 191BE154D 397C9D440 5 05A1B6650 29835ADAD 2F6DDABE4 0976A607B 11BA92926 2456B1943 3E3FD608B 095E7584B 6 00CC66282 0560BE767 21EBAA7C6 2D8E9ACE3 198A9E285 05F3E73DD 13DA751A2 176B75E43 7 03D08ADC1 2254606FC 3C695D892 1DA9E0280 2CD4FF589 19B78A5A4 0CE67A7C6 12535A61C 8 0984647CF 0822BA46B 3EB2BC076 212596F54 11CC2E64E 120BADF9F 0DA72CEDE 30D0E106F 9 083CE5726 1F05DA925 169D93EF6 1FCADF3D3 08A5CF0BC 317C8508F 19BDCCFE7 0FACE3631 10 27583A466 1CB1634D5 03C7849F7 38C6CED00 1161C173A 15A645D3E 281A7ED92 076ADA797 11 33BA1AE8F 187F578EE 32473D69A 2458B703B 267E59071 0F317883B 3E7DEDBF1 3B9859BA7 12 0322609A3 20C4C957C 3FD638746 3FB716D79 36BD0CF1C 333B11B8F 0027ED1F2 3E7471BF3 13 3529922B1 0ECECBE04 1980B9B9E 38D60363F 18904BCED 108E3E5F1 34B95C446 338F51DAC 14 21FD50527 0EA2F7A31 1E294A159 114734A02 120B90BF3 3F3617C92 0129071E2 106640936 15 2B59354BB 275BF9761 39C6FF332 2004B3902 053F9DCB0 19D79A902 2B3125038 20649B43E 16 03A8A7A2B 091AE6721 18651FD9E 1F5415ECD 1B38EA62E 07FB0F422 3EB58896B 077FE4C7C : : : : : : : : : 127 21C33416F 18B894695 3AC062614 3537CF601 00A20A8B8 1CD10BAF5 394DF1DC0 0925851ED

However, the repeater, the RRH, and the like cannot be allocated another SA-Preamble because they are transmission objects included in one base station, not an independent base station. Looking at the SA-Preamble sequence in the IEEE 802.16m standard, it can be seen that the A, B, C, D, E, F, G, H is composed of eight sequence blocks (Tables 1 to 3 above). > Reference).

Therefore, in the present invention, each SA-Preamble sequence block is allocated equally so as not to overlap bands for the purpose of distinguishing the repeater and the RRH in one base station. For example, the base station uses E and F blocks, RRH # 1 uses G and H blocks, RRH # 2 uses A and B blocks, and RRH # 3 uses C and D blocks. It is.

In another implementation, the SA-Preamble sequence block may be allocated by applying a weight to the RRH or the repeater. For example, if RRH # 1 has a high weight, it allocates three A, B, and C blocks, if RRH # 2 has a low weight, only D blocks are allocated, and RRH # 3 and the base station have a medium weight. Allocate E, F blocks, G, and H blocks.

However, in case of dividing each SA-Preamble sequence block to distinguish the repeater and the RRH in one base station and assigning the SA-Preamble sequence block to the repeater and the RRH, the sequence length allocated to each LBS reference signal transmitting entity is shortened. In the LBS zone, a method of repeatedly transmitting in the frequency domain or the time domain using several LBS symbols may also be considered. In this case, although the length of the SA-preamble sequence is short, it is possible to obtain the effect of increasing the actual transmission power by repeatedly transmitting. Thus, performance degradation that may occur due to shortening of the SA preamble sequence length may be overcome.

On the other hand, although A, B, C, D, E, F, G, H has been described with an example in which eight sequence blocks are divided and repeated in the frequency domain, depending on the implementation, eight sequence blocks are divided and repeated in the time domain. Can be sent.

For example, through the five LBS symbols of the LBS zone in Figure 4, E, F block of the base station, G, H block of RRH # 1, A, B block of RRH # 2, C, D of RRH # 3 The block may be sent repeatedly. In another implementation, the E, F block, G, H block of RRH # 1, A, B block of RRH # 2, RRH # 3 of the base station through a plurality of LBS zones repeated during the LBS zone interval 400 C and D blocks may be repeatedly transmitted.

6 is a flowchart illustrating an operation of a terminal for an LBS service in a wireless communication system according to an exemplary embodiment of the present invention.

Referring to FIG. 6, the terminal receives LBS zone and LBS symbol information from a base station through a MAC management message such as SFH (Superframe Header) or AAI_SCD in step 600, and the base station is neighbored for LBS service. LBS_ADV message including the base station ID information, GPS time, location information, etc. are received from the base station. The detailed LBS_ADV message format is shown in Table 4 below.

Name Size
(Bits) Value Usage Control Message Type AAI_LBS-ADV Position Indication One Represents absolute position whether using long format or short format. The value indicates:
0b0: long format is used
0b1: short format is used Type indication of short format One 0b0: short format including altitude is used
0b1: short formatexcluding altitude is used It is included only if Position Indication is 0b1. Absolute Position (Long Format) Longitude 40 Bit 0 ~ 5: longitude resolution 1-34: # of valid bits in fixed-point value of longitude value
35: LBS not supported Other: Reserved
Bit 6 ~ 14: longitude integer
Bit 15 ~ 39: longitude fraction Shall be included when Position Indication is set to 0b0. The transmitting ABS's coordinates. This Absolute Position (Long Format) shall only be used for the transmitting ABS and includes Longitude, Latitude and Altitude. Latitude 40 Bit 0 ~ 5: latitude resolution 1-34: # of valid bits in fixed-point value of longitude value
35: LBS not supported
Other: Reserved
Bit 6 ~ 14: latitude integer
Bit 15 ~ 39: latitude fraction Altitude 40 Bit 0 ~ 3: altitude type
1: meter
2: floors
Other: Reserved
Bit 4 ~ 9: altitude resolution 1-30: # of valid bits in fixed-point value of altitude value
31: LBS not supported
Other: Reserved
Bit 10 ~ 31: altitude integer
Bit 32-39: altitude fraction Absolute Position (Short Format) Longitude 16 (?) Longitude expressed in 2-15 parts of a degree The transmitting ABS's coordinates. This Absolute Position (Short Format) shall only be used for the transmitting ABS. It includes Longitude, Latitude and Altitude if type indication of short format is 0b0.
It includes Longitude and Latitude only if Position Indication is 0b1. Latitude 16 (?) Latitude expressed in 2-16 parts of a degree Altitude 16 Bit 0-15: altitude in meters above sea level GPS Time GPS time in units of frame duration 22 Information about GPS time and time accuracy. GPS frame transmission time offset 10 GPS time accuracy 5 Frequency accuracy 8 Information about the frequency accuracy Number of BS 8 Number of neighbor BSs included in this message that are identified using the BSID BSID 16 Shall be included when Number of BS> 0
16-bit LSB of unique 48-bit identifier of the neighbor BS for number of BS. Number of BS Index 8 Number of neighbor BSs included in this message that are identified using an index to their position in the AAI_NBR_ADV message Configuration change count for AAI_NBR_ADV 8 Shall be included when Number of BS Indices> 0 Neighbor BS Index 8 Shall be included when Number of BS Indices> 0 Index that corresponds to the position of the BS in the NBR-ADV message Relative Position Indication One Represents relative position whether including altitude. The value indicates:
0b0: altitude is included
0b1: altitude is not included Relative position Longitude 16 Distance east of reference point in meters Shall be included when Number of BS> 0 or when Number of BS Indices> 0 This Relative Position is used to provide the absolute position of an ABS. When this Relative Position is included, it provides the position of a neighbor ABS relatively to the transmitting ABS. If the Relative Position is set to 0b0, altitude in not included.
Latitude 16 Distance north of reference point in meters Altitude 16 Distance above of reference point in meters Number of LBS RS 3 Indicates the number of LBS RS in a cell. LBS RS Index 3 Indicates the sequence block index assigned to each object transmitting LBS RS LBS RS symbol Index 3 Indicates the symbol index in which LBS RS is transmitted Relative Position Indication One Represents relative position whether including altitude. The value indicates:
0b0: altitude is included
0b1: altitude is not included The position information of the objectives which transmit the reference signals. Relative position Longitude 16 Distance east of reference point in meters The position information of the objectives which transmit the reference signals. Latitude 16 Distance north of reference point in meters Altitude 16 Distance above of reference point in meters

In the present invention, the UE uses the LBS_ADV message to reuse the SA-preamble, the number of LBS reference signals (Number of LBS RS) transmitted in one cell, to each transmission object transmitting the LBS reference signal It receives the index of the allocated SA-preamble sequence block (LBS RS Index), the symbol index (LBS RS symbol) to be transmitted LBS RS, and the relative position (Relative position) of the transmission object for transmitting the reference signal.

Then, the terminal determines whether the LBS zone in step 602, the LBS zone, in step 604 a plurality of base stations / multiple repeaters for the reference signals reused SA-preamble or midamble for the LBS service during the LBS symbol interval in step 604 Receive from multiple RRHs.

In step 606, the terminal selects a transmission object that transmits the reference signal from the received reference signals based on the Number of LBS RS, LBS RS Index, LBS RS symbol Index, and Relative position information received through the LBS_ADV message. To judge. In addition, the arrival time of the reference signals is checked.

In step 608, the terminal determines whether the reporting period is for the LBS service, and in step 610, configures a report message including the arrival time information of the reference signal for each transmitting entity that transmitted the reference signal in the reporting period. In step 612, a report message for the configured LBS service is transmitted to the base station.

7 is a flowchart illustrating an operation of a terminal for an LBS service in a wireless communication system according to an exemplary embodiment of the present invention.

Referring to FIG. 7, in step 700, the base station broadcasts LBS zone and LBS symbol information through a MAC management message such as SFH (Superframe Header) or AAI_SCD. Broadcasts an LBS_ADV message including information, GPS time, location information, and the like. In this case, the LBS_ADV message of Table 1 includes SA-Preamble sequence information (Number of LBS RS, LBS RS Index, LBS RS symbol Index and Relative position) allocated to the relay and the RRH.

Thereafter, the base station determines whether the LBS zone in step 702, when the LBS zone, the process proceeds to step 704, so that the terminal can distinguish the base station / repeater / RRR, the SA preamble or midamble to reuse the LBS reference signal Create The SA preamble or the midamble sequence is divided into a plurality of blocks (see Tables 1 to 3).

For example, the SA preamble sequence consists of eight subblocks (A, B, C, D, E, F, G, H), and uses the A and B blocks as the only reference signals of RRH # 1, and C , D block is used as the only reference signal of RRH # 2, E, F blocks are used as the only reference signal of RRH # 3, and F, G blocks are used as the only reference signal of RRH # 4. Here, the subblock allocation of the SA preamble sequence is just one example, and the number of subblocks may be variously allocated to the RRH according to implementation.

At this time, the subblocks of the SA preamble sequence reused for each RRH are repeatedly allocated in corresponding LBS symbols in the frequency domain or repeatedly allocated over a plurality of LBS symbols in the time domain. For example, as shown in FIG. 5, RRH # 1 is a subcarrier (G, H) of the SA preamble sequence is repeatedly transmitted in the frequency domain, or LBS RS symbols 0, 1 in the LBS zone of FIG. Subblocks G and H of the SA preamble sequence are repeatedly transmitted through 2, 3, and 4. In another implementation, subblocks G and H of the SA preamble sequence may be repeatedly transmitted through the LBS zones repeated during the LBS zone interval.

In step 706, the base station transmits a reference signal for which the SA preamble is reused for the LBS service to the terminal during the LBS symbol period.

In step 708, the base station determines whether the reporting period is for the LBS service, and in step 710, the base station receives a reporting message for the LBS service from the terminal in the reporting period. The report message may include a time point at which the LBS reference signal arrives and a transmitting entity transmitting the reference signal, and the report message may be transmitted through a scanning report message or a separate control message.

In step 712, the base station estimates a distance based on the arrival time of the LBS reference signal included in the report message and information on the transmission subject of the reference signal, and determines the location of the terminal based on the estimated distance. Decide

8 illustrates a base station apparatus for LBS service in a wireless communication system according to an embodiment of the present invention.

Referring to FIG. 8, the base station includes a control unit 802, an OFDM transmitter 800, an OFDM receiver 804, an LBS resource allocation unit 806, an LBS report analyzer 808, and an RRH 810. .

The control unit 802 controls the overall operation of the base station, and controls the LBS service in addition to the present invention. For example, the control unit 802 broadcasts LBS zone and LBS symbol information through a MAC management message such as SFH (Superframe Header) or AAI_SCD, and neighbor base station ID information and GPS time for LBS service. Broadcasts an LBS_ADV message including location information.

The LBS resource allocator 806 reuses the SA preamble or the midamble and allocates them to the base station / relayer / RRH, respectively. For example, the SA preamble sequence consists of eight subblocks (A, B, C, D, E, F, G, H), assigns A and B blocks to RRH # 1, and assigns C and D blocks. Assign to RRH # 2, assign to E, F blocks, and assign F, G blocks to RRH # 4.

At this time, the subblocks of the SA preamble sequence reused for each RRH are repeatedly allocated in corresponding LBS symbols in the frequency domain or repeatedly allocated over a plurality of LBS symbols in the time domain. For example, as shown in FIG. 5, RRH # 1 is a subcarrier (G, H) of the SA preamble sequence is repeatedly transmitted in the frequency domain, or LBS RS symbols 0, 1 in the LBS zone of FIG. Subblocks G and H of the SA preamble sequence are repeatedly transmitted through 2, 3, and 4. In another implementation, subblocks G and H of the SA preamble sequence may be repeatedly transmitted through the LBS zones repeated during the LBS zone interval.

The OFDM transmitter 800 receives data and control information from the controller 802, performs OFDM modulation, and transmits the data through an antenna. For example, the OFDM transmitter 800 OFDM modulates a reference signal in which SA preamble is reused for an LBS service during an LBS symbol period and transmits the OFDM signal to the terminal.

The OFDM receiver 804 OFDM demodulates data and information received from the antenna and provides the demodulated data to the controller 802. For example, a report message for the LBS service is received from the terminal, and is provided to the controller 802 after OFDM demodulation. The report message includes a time at which the LBS reference signal arrives and a transmitting entity transmitting the reference signal.

The LBS report analyzer 808 estimates a distance based on a time when the LBS reference signal included in the report message arrives and information on a transmitting subject of the reference signal, and determines the position of the terminal based on the estimated distance. Decide

9 illustrates a terminal device for LBS service in a wireless communication system according to an embodiment of the present invention.

Referring to FIG. 9, the terminal includes a control unit 900, an OFDM transmitter 902, an OFDM receiver 904, and an LBS signal determination unit 906.

The controller 802 controls the overall operation of the terminal, and controls the LBS service in addition to the present invention. For example, the control unit 802 receives LBS zone and LBS symbol information from a base station through a MAC management message such as SFH (Superframe Header) or AAI_SCD, and the base station is a neighbor base station ID for LBS service. LBS_ADV message including information, GPS time, location information, etc. is received from the base station to support the LBS service.

In addition, the controller 802 configures a report message including the arrival time information of the reference signal for each transmission entity that transmits the reference signal in the reporting period.

The OFDM receiver 904 OFDM demodulates data and information received from the antenna and provides the demodulated data to the controller 900. For example, during the LBS symbol period, reference signals from which SA-preamble or midamble is reused for LBS service are received from a plurality of base stations / multiple repeaters / multiple RRHs.

The LBS signal determining unit 906 transmits a reference signal from the received reference signals based on the Number of LBS RS, LBS RS Index, LBS RS symbol Index, and Relative position information received through the LBS_ADV message. Judge. In addition, the arrival time of the reference signals is checked.

The OFDM transmitter 902 receives data and control information from the controller 900, performs OFDM modulation, and transmits the data through an antenna. For example, a report message for the configured LBS service is transmitted to the base station through the antenna.

Meanwhile, in the detailed description of the present invention, specific embodiments have been described, but various modifications are possible without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined not only by the scope of the following claims, but also by the equivalents of the claims.

RRH: 810, LBS Resource Allocation: 806, LBS Report Analyzer: 808

Claims (28)

A method of operating a base station for location based service (LBS) in a wireless communication system,
Assigning to the plurality of devices by reusing a synchronization sequence to distinguish a plurality of devices in the same service area;
Transmitting a reference signal to a terminal through the plurality of devices in a plurality of LBS zones during an LBS zone;
Receiving control information for an LBS service from the terminal;
And determining the location of the terminal based on the control information.
The method of claim 1,
The synchronization sequence may utilize different code sequences for distinguishing LBS reference signals, and may include a SA advanced preamble and a midamble divided into a plurality of subblocks defined in the IEEE 802.16m standard. midamble).
The method of claim 1,
The device is one of a repeater and a remote radio head (RRH).
The method of claim 1,
The control information includes at least one of time information of the terminal receiving the reference signal, information of the transmitting entity transmitting the reference signal,
The transmitting entity is one of a repeater, an RRH, and a base station.
The method of claim 1,
The process of allocating the synchronization sequence to the plurality of devices by reusing the synchronization sequence may include:
Dividing the synchronization sequence into a plurality of subblocks and mapping at least one or more subblocks to respective devices.
The method of claim 1,
The process of transmitting a reference signal to the terminal through the plurality of devices in the plurality of LBS zones,
And transmitting the reused synchronization sequence repeatedly in the frequency domain.
The method of claim 1,
The process of transmitting a reference signal to the terminal through the plurality of devices in the plurality of LBS zones,
And transmitting the reused synchronization permutation repeatedly using symbols of the LBS zone, or repeatedly transmitting the reused synchronization permutation using LBS zones during the LBS zone interval.
The method of claim 1,
The method further includes the step of broadcasting information on the reused synchronization sequence,
The reused synchronization permutation information includes the number of reference signals transmitted in the same service area (Number of LBS RS), the block index (LBS RS Index) allocated to each transmitting object transmitting the reference signal, and the reference signal transmitted. And at least one of an LBS RS symbol index and a relative position of a transmitting object transmitting the reference signal.
A method of operating a terminal for a location based service (LBS) in a wireless communication system,
During the LBS zone, receiving a reference signal in a plurality of LBS zone,
Determining a transmitting entity transmitting the reference signal from the reference signal;
Reporting at least one of transmission entity information transmitting the determined reference signal and arrival time information of the reference signal to a base station,
The reference signal is characterized in that the synchronization sequence is reused and transmitted through the plurality of devices to distinguish the plurality of devices in the same service area.
The method of claim 9,
The synchronization sequence is characterized in that one of the SA (Secondary Advanced Preamble) and the midamble (midamble) divided into a plurality of subblocks.
The method of claim 9,
The device is one of a repeater and a remote radio head (RRH).
The method of claim 9,
The transmitting entity is one of a repeater, an RRH, and a base station.
The method of claim 9,
The process of determining the transmission entity that transmitted the reference signal,
Detecting a reused synchronization sequence from the reference signal,
And searching for a transmission entity corresponding to the reused synchronization sequence.
The method of claim 9,
Receiving information on the reused synchronization permutation,
The reused synchronization permutation information includes the number of reference signals transmitted in the same service area (Number of LBS RS), the block index (LBS RS Index) allocated to each transmitting object transmitting the reference signal, and the reference signal transmitted. And at least one of an LBS RS symbol index and a relative position of a transmitting object transmitting the reference signal.
A base station apparatus for location based service (LBS) in a wireless communication system,
An LBS resource allocation unit for reusing a synchronization sequence and allocating the plurality of devices in the same service area to allocate the plurality of devices;
During the LBS zone, a transmitter for transmitting a reference signal to the terminal through the plurality of devices in a plurality of LBS zone,
Receiving unit for receiving the control information for the LBS service from the terminal,
And a report analyzer for determining a location of the terminal based on the control information.
16. The method of claim 15,
The synchronization sequence is characterized in that the one of the SA (Secondary Advanced Preamble) and the midamble (midamble) divided into a plurality of subblocks.
16. The method of claim 15,
And the device is one of a repeater and a remote radio head (RRH).
16. The method of claim 15,
The control information includes at least one of time information of the terminal receiving the reference signal, information of the transmitting entity transmitting the reference signal,
And the transmitting entity is one of a repeater, an RRH, and a base station.
16. The method of claim 15,
The LBS resource allocation unit,
Dividing the synchronization sequence into a plurality of subblocks and mapping at least one or more subblocks to respective devices.
16. The method of claim 15,
The transmitting unit,
And transmitting the reused synchronization sequence repeatedly in the frequency domain.
16. The method of claim 15,
The transmitting unit,
And transmitting the reused synchronization permutation repeatedly using symbols of the LBS zone, or repeatedly transmitting the reused synchronization permutation using LBS zones during the LBS zone interval.
16. The method of claim 15,
Further comprising a control unit for broadcasting the information on the reused synchronization sequence,
The reused synchronization permutation information includes the number of reference signals transmitted in the same service area (Number of LBS RS), the block index (LBS RS Index) allocated to each transmitting object transmitting the reference signal, and the reference signal transmitted. And at least one of a symbol index (LBS RS symbol) to be used and position information of a transmission object transmitting a reference signal.
A terminal device for location based service (LBS) in a wireless communication system,
During the LBS zone, receiving unit for receiving a reference signal in a plurality of LBS zone,
An LBS signal determining unit for determining a transmission entity that has transmitted the reference signal from the reference signal;
And a controller for reporting at least one of at least one of transmission entity information transmitting the determined reference signal and arrival time information of the reference signal to the base station,
The reference signal is characterized in that the synchronization sequence is reused in order to distinguish a plurality of devices in the same service area is transmitted through the plurality of devices.
24. The method of claim 23,
The synchronization sequence is characterized in that the one of the SA (Secondary Advanced Preamble) and the midamble (midamble) divided into a plurality of subblocks.
24. The method of claim 23,
And the device is one of a repeater and a remote radio head (RRH).
24. The method of claim 23,
And the transmitting entity is one of a repeater, an RRH, and a base station.
24. The method of claim 23,
The LBS signal determination unit,
Detecting a reused synchronization sequence from the reference signal,
And searching for a transmission entity corresponding to the reused synchronization sequence.
The method of claim 9,
The controller receives the information on the reused synchronization permutation,
The reused synchronization permutation information includes the number of reference signals transmitted in the same service area (Number of LBS RS), the block index (LBS RS Index) allocated to each transmitting object transmitting the reference signal, and the reference signal transmitted. And at least one of a symbol index (LBS RS symbol) to be used and position information of a transmission object transmitting a reference signal.

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