KR20040015785A - Apparatus and method to effectively integrate repeater system and wireless common channel transmitter to produce unique identity signal in the down link of the repeater system in order to reduce the position estimation error of mobile station due to the repeater system in advanced forward link trilateration utilizing base station pilot signals in code division multiple access mobile communication systems - Google Patents

Abstract

PURPOSE: A method for effectively combining a repeater with WCCTs(Wireless Common Channel Transmitters) is provided to improve an error caused by a repeater in measuring the location of a mobile terminal in an AFLT(Advanced Forward Link Trilateration) method using a pilot channel of a CDMA mobile base station. CONSTITUTION: A terminal signal, received through a service antenna, is passed through a duplexer(4021) and combined with the terminal signals received through a plurality of other service antennas at a signal combiner(4011). The combined signal is transferred to a BTS after being filtered through a repeater filter block(4001). Downlink signals, inputted to the repeater filter block(4001), are outputted to the signal combiners(4051-405n) respectively connected to the service antennas. The signal combiners(4051-405n) respectively combine the downlink output signals of the repeater filter block(4001) with the unique identity signals of WCCT modules(4041-404n) and output the combined signals to power amplifiers(4031-403n). Each power amplifier(403n) amplifies the inputted signal and outputs it to each duplexer(402n). The downlink signals, passed through the duplexers(4021-402n), are transferred to terminals through the service antennas respectively.

Description

Effective Combining Method and Method of Repeater and Wireless Common Channel Transmitter for Reducing Error Caused by Repeater in Triangulation Measurement of Terminal Location Using Pilot Channel of Mobile Communication Base Station of Code Division Multiple Access [APPARATUS AND METHOD TO] EFFECTIVELY INTEGRATE REPEATER SYSTEM AND WIRELESS COMMON CHANNEL TRANSMITTER TO PRODUCE UNIQUE IDENTITY SIGNAL IN THE DOWN LINK OF THE REPEATER SYSTEM IN ORDER TO REDUCE THE POSITION ESTIMATION ERROR OF MOBILE STATION DUE TO THE REPEATER SYSTEM IN ADVANCED FOR LINKS DIVISION MULTIPLE ACCESS MOBILE COMMUNICATION SYSTEMS}

The present invention relates to a mobile communication system, and more particularly to a repeater system (REPEATER SYSTEM) for use in improving the mobile communication signal environment.

The repeater is a call of the DOWN LINK AND UP LINK, which relays the signal of the base station and transmits the signal of the terminal to the base station, especially in a shaded area or an area where a signal of a signal base station is hardly reached, such as an indoor or underground space. It is widely used for environmental improvement.

Recently, a triangulation positioning system for position measurement of a terminal detects a pilot channel signal received from three or more synchronized base stations, extracts a time difference of each pilot signal (TDOA). Use the triangulation method to find the POSITION SOLUTION. This method is well known as AFLT (ADVANCED FORWARD LINK TRILATERATION) and is currently being studied in many countries, including home and abroad. However, the implementation of AFLT has a lot of difficulties due to the repeaters used in the past. That is, when the terminal receives the base station relay signal output from the repeater, the terminal recognizes that the signal received from the repeater is the same as the transmission signal of the base station and recognizes it as a signal transmitted from the base station and calculates a TDOA with the other base station signal received. As a result, the position of the terminal is calculated. In this process, the repeater has its own time delay (time delay during signal arrival from the base station to the repeater and processing time delay until the repeater receives the base station signal, amplifies it, and retransmits it). ) Acts as an error of TDOA, so the position error of the terminal may occur from several hundred meters to several kilometers.

In order to overcome this problem, a method for distinguishing a base station signal from a repeater signal by adding a signal different from the code division multiple access signal to the base station relay signal outputted by the repeater in a code division multiple access system (Repeater-One solution) Repeater One is being introduced by Qualcomm. Qualcomm recently introduced a scheme for mixing the FM signal with the output signal of the repeater so that when the terminal equipped with the FM receiver receives the received signal, the downlink signal is received from the repeater. In the repeater source, since the divergence signal of the repeater is a code division multiple access type spread spectrum signal and the repeater identification signal is an FM signal, it is not easy for the terminal to find a direct correlation between the downlink signal and the FM signal of the repeater. That is, when a terminal receives both a downlink signal transmitted from a base station and a downlink signal transmitted from a plurality of repeaters in a cell area in which a plurality of repeaters transmit signals of a base station and a base station in a downlink, In addition, there is a problem in identifying which signal is an identifier of a plurality of downlink signals of the repeater that has transmitted the FM signal received.

Another way to overcome the position measurement error caused by the repeater is to distinguish the received repeater signal through an algorithm. This method measures the position and time delay values of all the repeaters in advance and determines whether the downlink signal received using the information is transmitted directly from the base station or through the repeater and registers if it is transmitted through the repeater. It may be possible to figure out which repeater was sent from. However, this method has a realistic problem of continuously managing repeater related information such as position and time delay values of 100,000 or more repeaters. In addition, when relying on such an algorithm, it is important to distinguish whether a signal received from a repeater or a base station is received in a signal environment such as a close-up area or an indoor confined space or an underground space where only a repeater signal is received. impossible.

The main object of the present invention is to utilize a wireless common channel transmitter (application number :) as a method for distinguishing a base station and a repeater signal in order to improve the AFLT terminal location measurement problem in a CDMA mobile communication system. To provide a way to.

Another object of the present invention is to provide a method of utilizing a wireless common channel transmitter in a repeater to improve the AFLT terminal location measurement problem in a CDMA mobile communication system, and to implement the method in the repeater device. In providing.

Another object of the present invention is to determine the location of a terminal in an area where it is impossible to measure the location of an AFLT terminal such as an indoor or underground space where only a downlink signal relayed through a repeater is received in a code division multiple access (CDMA) mobile communication system. The present invention provides a method of utilizing a wireless common channel transmitter in a repeater, and provides an implementation method in the repeater device.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a block diagram showing a signal relay device having the identification signal transmission function according to the first embodiment of the present invention.

Fig. 2 is a block diagram showing a signal relay device having the identification signal transmission function according to the second embodiment of the present invention.

3 is a diagram showing phases of pilot signals transmitted in a repeater device according to an embodiment of the present invention.

4 is a block diagram of a signal relay device having the identification signal transmission function according to the third embodiment of the present invention.

Fig. 5 is a block diagram showing a signal relay device having the identification signal transmission function according to the fourth embodiment of the present invention.

6 is a block diagram showing a modular radio common channel transmitter mounted on an existing repeater by applying the first and second embodiments of the present invention.

Hereinafter, the present invention provides a common channel signal transmission apparatus and method for space recognition in a mobile communication system (application number: 10-2002-0008785) and a common channel signal transmission device for space recognition in a mobile communication system. Method of improving and implementing (application number: 10-2004-0006749) ”will be described in detail with reference to the accompanying drawings, preferred embodiments of the present invention.

First, descriptions of the present invention and core introductions of the present invention are not directly related, and the technical details and details thereof implemented in the existing mobile communication system will be omitted. Existing techniques and theoretical analyzes necessary for the description of the present invention are replaced with a brief description.

Hereinafter, an embodiment of a signal repeater system using a forward common channel signal transmission apparatus for AFLT terminal position measurement will be described.

1 illustrates an implementation of a repeater system combined with a wireless common channel transmitter (WCCT) according to the present invention. For reference, in FIG. 1, since the structure or the implementation method of the entire repeater are the contents previously developed, only the parts necessary for the description of the present invention are indicated. 1 is a downlink amplification outputted to a service antenna of a repeater in a process in which a downlink or a forward link transmitted from a base station is retransmitted after noise is removed or signal amplified through a repeater; A method of adding a unique identity signal to a signal is illustrated. The downlink signal that is noise canceled and signal amplified by the repeater is directly transmitted through the service antenna 1002 in the existing repeater. A method of adding a unique identification signal to a repeater output signal according to the present invention includes a repeater downlink signal and a wireless common channel transmitter basic module (blocks 1011, 1021, 1031 to 103Y, 1041, 1051, 1052, and 1053) output to a service antenna. The original identification signal outputted from the patent application) is mixed in a mixer 1001 and then outputted, and the output signal of the mixer 1001 is received by the service antenna 1002 and the wireless common channel transmitter. to be. The process of generating a unique identification signal by the wireless common channel transmitter module which receives the output signal of the signal mixer 1001 is described in the "Application and Improvement Method of the Common Channel Signal Transmitter for Space Recognition in a Mobile Communication System (Application) No. 10-2004-0006749), so detailed description thereof will be omitted.

The implementation scheme of FIG. 2 is a scheme in which the same downlink signal and the unique identification signal are output through all service antennas connected to the repeater. In the implementation scheme of FIG. 1, the output signal of the signal mixer 1001 may be distributed to a plurality of service antennas, and may have the same effect as the implementation scheme of FIG. 2. However, when the repeater downlink output signal input to the signal mixer 1001 is one of the pre-distributed signals, the unique identification signal is output only at the service antenna to which the wireless common channel transmitter module is coupled.

2 is another implementation of a repeater system combined with a wireless common channel transmitter (WCCT) according to the present invention. First, the downlink transmitted from the base station is received wirelessly through the donor antenna of the repeater according to the type of repeater (RF repeater, etc.) or received through the wired connection to the repeater (optical repeater). Etc). 2 is a combination method of a wireless common channel transmitter and a repeater system implemented in a downlink repeater receiving end received through a wired or wireless repeater. The base mixer downlink signal input by a donor antenna or a wire and the unique identification signal which is an output signal of the wireless common channel transmitter module (blocks 2011, 2021, 2031 to 203Y, 2041, 2051, 2052, and 2053) are mixed in the signal mixer 2001. And output. The output signal of the signal mixer is input to the wireless common channel transmitter module and used to control the phase and signal strength of the unique identification signal.

1 and 2 illustrate that the wireless common channel transmitter module includes a function of the signal mixers 1001 and 2001, the wireless link to a downlink input terminal or a downlink output terminal of an existing repeater. The common channel transmitter module can be inserted and operated simply by plugging it in. 6A and 6B illustrate an implementation plan for such a case, in which the wireless common channel transmitter module is inserted into the downlink output terminal of the repeater ([FIG. 6A]), the downlink of the repeater 6011. The wireless common channel transmitter module 6012 receives the link output signal and the final signal in which the repeater downlink output signal and the unique identification signal are mixed is outputted to the service antenna. In addition, FIG. 6B illustrates an implementation method for inserting and connecting a wireless common channel transmitter module to a repeater input terminal for a base station downlink (FIG. 6B). The downlink output signal 6061 of the base station is illustrated. The wireless common channel transmitter module 6022 receives the input, mixes the unique identification signal with the downlink output signal of the base station, and outputs the final mixed signal to the repeater 6023, and the repeater returns the input signal to the service antenna 6024. The implementation method is shown.

FIG. 3 illustrates when an output signal from a service antenna according to the implementations of FIGS. 1 and 2 is received by a mobile terminal of a code division multiple access method (ideal reception situation as an example). ) Is a diagram illustrating a signal search result according to the operation of the signal searcher inside the terminal. In particular, the example of [FIG. 3] shows that the wireless common channel transmitter module used in [FIGS. 1] and [FIG. 2] utilizes only two PN offsets (that is, Y = 2 and [FIGS. 1] and [FIG. 2]). In this case, only two pilot channel generators, such as 1031 and 2031, are used.) Signal selector and combiner (Signal Selector and Combiner, 1041,) in the wireless common channel transmitter module used in FIGS. 1 and 2. The signal selection method of 2041 has no time delay among input signals (pilot channel time delay components having delays D1, D2, ..., Dk) after the first pilot channel is time-delayed in various sizes. 0) When a signal component is selected and a signal component having an arbitrary time delay is selected among the second pilot channel input signals (Y = 2). The three graphs shown in FIG. 3 are the results of searching for a pilot channel of a service base station, a first pilot channel, and a second pilot channel output from a wireless common channel transmitter module by a pilot channel searcher inside the terminal. To illustrate. First, a signal whose relative received signal strength (Ec / Io, energy-to-interference ratio per chip) is Rs at the center of the searcher window centered on the phase of the service pilot channel received as a result of the search for the service pilot channel. Correlation results are shown. The graph shown in the middle of FIG. 3 shows a signal search result of the mobile communication terminal for the first pilot channel of the wireless common channel transmitter module. Since the first pilot channel has no time delay (Delay = 0), the searcher window is shifted by the PN offset of the first pilot channel based on the phase of the received service pilot channel. The pilot channel search result (first pilot channel search result) shows a signal correlation result of W1 being a relative reception strength at the center point of the search window. Accordingly, the service pilot channel and the first pilot channel have the same phase in the search window. Accordingly, when the service pilot channel has the same phase as that of the first pilot channel, the terminal may determine the service pilot channel as the base station downlink signal transmitted after being relayed from the repeater. However, as shown in the third graph of FIG. 3, the second pilot channel is selected to have an arbitrary time delay (Delay = Δchips = Dj, j = 1, 2, ..., k). The search result of the pilot channel searcher shows a signal correlation result of W1 as a relative reception strength at a point delayed by ?? chip from the point at which the signal correlation result value of the first pilot channel appears. In accordance with the measurement result shown in FIG. 3, the terminal transmits identification information of PN offset 1, Delay = 0, PN offset 2, and Delay = Δ to the base station (if necessary) so that the terminal has the identification information. It can be seen that the received service pilot channel is located at and relayed from the repeater having the identification information.

The implementation of FIG. 4 illustrates a method of combining the wireless common channel transmitter module with an N-input repeater (In-Building Repeater) by expanding the implementation scheme of FIG. 1. First, block 4001 is a block that includes the main filter functions of the repeater such as noise cancellation and filtering. First, the signal flow for the uplink is as follows. The terminal transmission signal received through the service antenna (in case of # 1) is mixed in the signal mixer 4011 with the terminal transmission signals received through a plurality of other service antennas after passing through the duplexer 4021 and input to the block 4001. After passing through the filtering process, it is delivered to the base station. The downlink signal received by the block 4001 is output to the signal mixers 405n, n = 1,2,3 ... N connected to each service antenna (#n, n = 1,2,3 ... N). do. The signal mixers 405n, n = 1,2,3 ... N are the downlink output signals of the block 4001 and the n (n = 1,2,3 ... N) th wireless public channel transmitter modules (WCCT Module, Inputs a unique identification signal of 404n, n = 1,2,3 ... N, and outputs a mixed signal to an amplifier (Power Amplifier, 403n, n = 1,2,3 ... N) and an amplifier 403n. Amplifies the received signal and outputs it to the duplexers 402n, n = 1,2,3 ... N, and the downlink signal passing through the duplexer 402n is a service antenna (#n, n = 1,2, 3 ... N) is delivered to the terminal. Also, as shown, the wireless common channel transmitter module 404n, n = 1, 2, 3 ... N inputs the output signal of the signal mixer 405n, n = 1, 2, 3 ... N. The output signal of the signal amplifiers 403n, n = 1, 2, 3 ... N may be used as an input instead of the output of the signal mixer 405n. In the figure, the signal amplifiers 403n, n = 1,2,3 ... N and the signal mixers 405n, n = 1,2,3 ... N are implemented in a linear system. Even if it is, the same result is finally output. In addition, the signal amplifiers 403n, n = 1, 2, 3 ... N may be absorbed and implemented in other blocks in the repeater without being present at the positions shown in some cases. The change according to the position of 403n, n = 1, 2, 3 ... N) is omitted. According to the implementation method of FIG. 4, when the in-building repeater has one service antenna for each floor, the terminal searches for a unique identification signal of the wireless common channel transmitter coupled to each service antenna. Locating can be done on each floor. In addition, when a terminal located in a high-rise building receives a downlink signal from a repeater in a building and simultaneously receives a downlink signal transmitted and received from a service base station and a neighboring base station outside the building, the repeater signal when trying to determine the location by AFLT. Can be easily distinguished, so triangulation by accurate AFLT is easy.

5 shows a combined implementation method of another repeater and a wireless common channel transmitter according to the present invention. First, among the blocks of [FIG. 5], the blocks having the same functions as the blocks of [FIG. 4] are block 5001 (same as block 4001), block 5011 (same as block 4011), block 5021 (same as block 4021), block Detailed descriptions of the functions are omitted as 5031 to 503N (the same as blocks 4031 to 403N) and blocks 5051 to 505N (the same as blocks 4051 to 405N, respectively). In addition, blocks corresponding to blocks 5051, 5061, 5071 to 507Y, 5081, 5091 to 509N, 5091 'to 509N', and 5091 “to 509N” are used to improve the common channel signal transmission apparatus for space recognition in a previously applied mobile communication system. And the same structure and implementation diagram as the common channel transmitter described in "Application Method (Application No.:10-2004-0006749)", and a detailed description thereof will be omitted. In the implementation method of FIG. The input signal to the wireless common channel transmitter is a mixed signal of the output signal (relayed downlink signal) of the block 5001 and each of the identification signals of the wireless public channel transmitter, and each unique identification signal output from the wireless public channel transmitter. (Output signals of blocks 509n, n = 1,2, ... N) are output to the signal mixers 505n, n = 1,2, ... N, respectively, so that each signal mixer 505n, n = 1,2 N, ... N) are mixed with the downlink signal to each signal amplifier 503n, n = 1,2, ... N ) Through the duplexer (502n, n = 1,2, ... N) connected to the n (n = 1,2, ... N) th service antenna, so that the signal output from each service antenna is transmitted by the base station. It becomes one downlink signal and one unique identification signal .. The implementation plan of FIG. 5 may also be an implementation example of an in-building repeater, and may be implemented in the building according to the implementation plan of FIG. (In-Building) When the repeater has one service antenna for each floor, the location of the terminal that has searched for the unique identification signal of the wireless common channel transmitter coupled to each service antenna may be determined for each floor. When a terminal located in a high-rise building receives a downlink signal from a repeater in a building and simultaneously receives a downlink signal transmitted from an out-of-building service base station and a neighboring base station, the location of AFLT is determined. Doha case can make it easy to distinguish a repeater signal is a triangular measurement is easily by accurate AFLT. The implementation method of FIG. 4 is an implementation example in which a wireless common channel transmitter module for generating one unique identification signal is provided for each service antenna of an in-building repeater. Equipped with a wireless public channel transmitter that generates as many unique identification signals as the number of service antennas connected to an in-building repeater, and a plurality of signals output from the wireless public channel transmitters and signals output from each repeater in the building An implementation method of mixing one out of two unique identification signals and outputting the same to a service antenna is illustrated.

As described above, the implementation method of the repeater combined with the wireless common channel transmitter according to the present invention uses only the same code division multiple access signal to distinguish the repeater signal, and thus the signal of a communication system other than the receiver of the code division multiple access method. Since it does not require an additional receiver for reception, it can be used in existing terminals unlike the existing Qualcomm method (Repeater One). In addition, the existing Qualcomm's method using the FM signal as an identification signal can be significantly different from the downlink signal arrival area of the code division multiple access method of the repeater and the FM signal reception area, and it is difficult to check whether the same signal source is present. The implementation manner according to the present invention is very easy and clear as can be seen in the example of FIG.

As described above, an implementation method of a repeater combining a wireless common channel transmitter according to the present invention is effective in distinguishing a base station from a repeater signal in order to improve the AFLT terminal location measurement problem in a code division multiple access (CDMA) mobile communication system. That's the way.

Claims (1)

Implementation of Repeater Using Wireless Public Channel Transmitter