KR970078079A - Base Station Synchronization Method Using Pilot Signal in Code Division Multiple Access System - Google Patents

Abstract

The present invention relates to a synchronization method between base stations in a code division multiple access system, and in order to provide an inter-base station synchronization method of synchronizing base stations using pilot signals of adjacent base stations in a code division multiple access mobile communication system, After receiving each pilot signal from the base station, the measurement base station detects the correlation phase energy of the adjacent base station to check whether the pilot phase is occupied, calculates the signal-to-interference ratio (SIR), and then searches for the entire period of the pseudo noise A first step 301 to 303, A second step (304) of repeating the steps from the first step (301 to 303) after shifting the phase point of the pilot code if the search for the full cycle of the PN code is not completed; And after the PN code search has been completed, the propagation delay time due to the base station and the propagation delay is corrected and the pilot phase error for each base station is calculated. Then, the phase error of the adjacent base station is measured according to the signal- (305 to 308) for performing phase correction by subjectively coupling and then transmitting a calibrated pilot signal, thereby achieving a simple cost reduction by performing inter-base station synchronization.

Description

Base Station Synchronization Method Using Pilot Signal in Code Division Multiple Access System

Since this is a trivial issue, I did not include the contents of the text.

FIG. 2 is a block diagram of a code division multiplexing (OFDM) system of a cellular system, FIG. 3 is a processing flow chart of a synchronization method between base stations using a pilot signal according to the present invention, FIG. 4 is an example of a configuration for the pilot phase detection and signal-to-interference ratio measurement process, FIG. 5 is an example of a configuration for the phase error estimation and correction process, And FIG. 7 is an explanatory diagram of simulation results.

Claims (7)

In a base station synchronization method applied to a code division multiple access system, a measuring base station that receives a pilot signal from each neighboring base station detects correlation energy to determine whether the pilot phase of the neighboring base station is occupied and calculates a signal-to-interference ratio (SIR) A first step (301 to 303) of determining whether a search for a full cycle of a PN (Pseudo Noise) code is completed; If it is determined that the search for the full period of the PN code is not completed as a result of the first step (301 to 303), a second step of repeating the steps from the first step (301 to 303) after moving the phase point of the pilot code (304); And if it is determined in the first step 301 to 303 that the search for the entire PN code cycle is completed, the base station corrects the propagation delay time due to the propagation delay and calculates the pilot phase error for each base station, And a third step (305 to 308) of performing a phase correction by combining weights according to a signal-to-interference ratio with respect to a phase error with respect to a phase error of the pilot signal, and then transmitting a corrected pilot signal. The method of claim 1, wherein the correlation energy R _p (ti + θi) of the first stage (301 to 303), (T) is an i-th adjacent base station pilot phase offset, (i) is an asynchronous base station element, and (iii) N is the number of adjacent base stations. 3. The method of claim 2, wherein the pilot phase occupancy of the first step (301 to 303) (V _T : threshold value for confirming whether the pilot synchronization phase is occupied). 4. The method of claim 3, wherein the signal-to-interference ratio (SIR) of the first step (301 to 303) (Where A is a pilot demodulation signal value, and? ^{2 is a} dispersion of interference terms). The method according to claim 1, wherein the phase error of the third step (305 to 308) Quot; (Wherein, τk _i: adjacent cell measurement the base station k propagation delay from i base station, (x _k, y _k, z _k): k base station location coordinates, (x _i, y _i, z _i): i the base station position coordinates, ν : Propagation speed). ≪ / RTI > 6. The method of claim 5, wherein the phase correction of the third step (305 to 308) Quot; And the base station synchronization method. 2. The method of claim 1, wherein the phase correction of the third step (305 to 308) is performed when repeating the phase correction process for each adjacent base station (phase correction ratio in lambda repetition process). ※ Note: It is disclosed by the contents of the first application.