Primary cell searching method for long term evolution (LTE) system

Abstract

The invention discloses a primary cell searching method for a long term evolution (LTE) system. The method comprises that: user equipment (UE) generates local primary synchronous signals and local secondary synchronous signals corresponding to each frequency point according to frequency point information stored in a BA table; for each frequency point, the UE receives data and calculates correlation power values between the local primary synchronous signal of the frequency point and the received data and between the local secondary synchronous signal of the frequency point and the received data; the UE performs subsequent timing rough synchronization, timing precise synchronization, frequency rough synchronization, wireless frame synchronization, frequency precise synchronization and cell broadcast message reading processes according to an order from greater correlation power values to lower correlation power values corresponding to each frequency point; and if a cell broadcast messageis accurately read on a selected frequency point, the UE selects a cell of the frequency point for residence. By the technical scheme provided by the invention, the blindness of frequency point selection from the BA table in a primary cell searching process is reduced, and the times for reading the cell broadcast message on a wrong frequency point by the UE can be effectively reduced, thereby shortening primary cell searching time and improving primary cell searching efficiency.

Description

technical field [0001] The present invention relates to a cell initial search technology of a mobile communication system, in particular to a cell initial search method for a long-term evolution (abbreviation, LTE) system. Background technique [0002] The LTE system is a further evolution of the third-generation mobile communication system. In the LTE system, the single carrier frequency division multiple access (SC-FDMA) technology is used in the uplink, and the orthogonal frequency division multiple access is used in the downlink. (abbreviation, OFDMA) technology. [0003] Orthogonal Frequency Division Multiplexing (abbreviated, OFDM) technology is a special multi-carrier transmission scheme, which can be regarded as a modulation technology and a multiplexing technology. The basic principle is: divide the channel into several orthogonal sub-channels, convert high-speed data signals into parallel low-speed sub-data streams, and modulate them for transmission on each sub-c...

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Problems solved by technology

[0028] However, there are still some problems in the existing cell initial search method with BA table. From the above process, it can be seen that the method of judging the frequency point of the cell suitable for camping is determined according to the interpretation result of the cell broadcast message. The BA table contains multiple working frequency points of the cell. The method of the prior art still has a certain degree of blindness in the process of using the frequency points in the BA table for the initial search of the cell, resulting in the possibility that the UE may perform a search on a large number of wrong frequency points. PBCH channel analysis and cell broadcast message interpretation work will take a lot of time, reduce the efficiency of the initial cell search, and thus affect the performance of the terminal

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