A method and device for detecting an LTE downlink primary synchronization signal based on circular convolution

Abstract

The invention discloses a long term evolution (LTE) downlink main synchronization signal detection method and device based on cyclic convolution. The detection method comprises steps that S1, received LTE downlink baseband signals are directly extracted to acquire data after downsampling, FFT transformation is carried out after conjugation, and frequency domain data is acquired; S2, the frequency domain data acquired in the step S1 realizes complex multiplication with a local frequency domain PSS sequence; S3, IFFT transformation of a complex multiplication result of the step S2 is further carried out to acquire a result set of cyclic convolution of the downlink signal after present sampling and the local time domain PSS, a maximum normalization value is selected as a last output result; and S4, a decision threshold is employed for the maximum normalization value of the step S3 to estimate a number of the PPS sequence and the half-frame timing time. The detection method is advantaged in that quite strong frequency offset prevention and interference prevention capabilities are realized, quick and accurate PSS sequence detection can be further realized, and LTE downlink synchronization performance is improved.

Description

technical field [0001] The invention belongs to the field of wireless communication testing and electronic measuring instruments, and in particular relates to a method and device for detecting an LTE downlink main synchronization signal based on cyclic convolution. Background technique [0002] LTE (Long Term Evolution, short for Long Term Evolution) has the characteristics of flexible configuration of bandwidth, low delay, high data rate, large capacity and so on. It is the standard for mainstream evolution to 4G technology. In the LTE system, when the user equipment is powered on within the coverage of a cell system, in order to access the network, it must first obtain the primary synchronization signal (PSS for short) and secondary Synchronization signal (SSS) to detect, this is the cell search process. After the cell search is completed, timing synchronization, carrier frequency offset and ID of the cell can be obtained. [0003] Primary synchronization signal detectio...

AI Technical Summary

Problems solved by technology

In the downlink channel, large frequency offset and high interference greatly damage the autocorrelation of the main synchronization signal, seriously affecting the performance of the main synchronization signal detection

The existing technology reduces the impact of frequency offset through pre-frequency offset processing and segment correlation, and reduces the impact of interference through multiple primary synchronization signal correlation accumulation; but they increase the complexity and detection delay of primary synchronization signal detection

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