Terminal and method for searching cell frequency point

Abstract

The present invention provides a terminal and method for searching cell frequency, and the method includes: for each frequency to be searched in a region of search, collecting a number of samples meeting one sub-frame, dividing the number of samples meeting one sub-frame into n signal segments, calculating the power spectral density of each signal segment, then based on the power spectrum density of each signal segment, deriving the characteristic value of the signal segment, reserving the maximum characteristic value in the n derived characteristic values as the characteristic value of the frequency to be searched, grouping the characteristic values of all of the frequencies to be searched in the whole region of search into a list of characteristic values, and considering the frequency corresponding to the maximum characteristic value in the list of characteristic values as the preferred frequency; wherein n=1. With the technical scheme of the present invention, an ACG trying in the prior art can be avoided, so as to prevent a series of problem arising therefrom, and the cross-coupling with peripheral modules can be reduced, the miss probability and error probability can be lowered greatly, as well as the performance of the frequency search can be improved.

Description

technical field [0001] The invention belongs to the field of frequency point search in communication and information technology, and in particular relates to a cell frequency point search terminal and method. Background technique [0002] TD-SCDMA is one of the three mainstream standards of 3G and has broad application prospects. The purpose of TD-SCDMA terminal frequency search is to find the frequency used by adjacent base stations, and then the terminal tries to connect. Through the frequency point search, the cell search can establish a normal processing flow on the selected working frequency. [0003] The frequency allocation scheme in the standard is as follows: [0004] Channel frequency interval: 200kHz, that is, all carrier frequencies are integer multiples of 200kHz [0005] Absolute wireless frequency point channel number: UARFCN is defined as N t =5*F 0.0MHz≤F≤3276.6MHz; [0006] Where F is the carrier frequency in MHz. [0007] UARFCN range in 1.28Mcps TDD...

AI Technical Summary

Problems solved by technology

[0013] 1) When the AGC gain is low and the actual signal power is small, most of the data does not obtain effectively many quantization bits, and division with too small data leads to frequent occurrence of abnormal eigenvalues, and this invalid result affects normal eigenvalue estimation

[0014] 2) Too many types of AGC attempts increase the probability of timing location misjudgment and reduce the overall performance of the cell search

[0016] 4) In order to ensure the performance of coarse timing, especially the reliability in low vehicle speed environment, often a single AGC gain must go through enough subframes, and multiple AGC attempts will greatly increase the processing time of cell search

In the case that the cell search process takes a long time, such frequent false positives will greatly increase the time of the search process

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