Joint estimation method of time deviation and frequency deviation

Abstract

The invention relates to the field of wireless communication, in particular to a joint estimation method of time deviation and frequency deviation in a third-generation mobile communication long-term evaluation system (short for 3G LTE). The method is characterized by comprising the following steps of: A. separating channel gain estimated values of PUSCH (Physical Uplink Shared Channel) demodulating reference signals (DM RS) of two time slots from received subframe data; B. calculating a correlation value of channel gain between two subcarriers which are respectively positioned on different PUSCH DM RS and have the frequency domain distance of s subcarrier intervals so as to obtain a joint estimation phase difference of time deviation and frequency deviation; and C. respectively obtaining the phase deviation of time deviation and frequency deviation according to the joint estimation phase difference of the time deviation and the frequency deviation so as to estimate a time deviation value and a frequency deviation value of a system. The method can be used for reducing the calculation amount of an estimation algorithm on the basis of ensuring estimating precision, thereby ensuring the real-time receiving performance of the system.

Description

technical field [0001] The present invention relates to the field of wireless communication, in particular to a joint estimation method of time offset and frequency offset in the third generation mobile communication long term evolution system (hereinafter referred to as 3G LTE). Background technique [0002] LTE adopts OFDM technology, and the frequency spectrum of subcarriers in the system covers each other, which has strict orthogonality. Due to the time-varying nature of the wireless channel, the instability of the transmitter and receiver crystal oscillators, and the Doppler frequency shift caused by the high-speed movement of the terminal, the frequency offset of the wireless signal will appear during transmission, which destroys the regularity of the subcarriers in the OFDM system. Interaction; the time offset caused by multipath transmission will cause serious inter-block interference (IBI). Only by estimating the frequency deviation and time deviation as accurately...

AI Technical Summary

Problems solved by technology

[0018] Obviously, this estimation scheme needs to estimate the time offset and frequency offset of the system through algorithms separately, which will bring a lot of correlation calculations, especially when estimating the frequency offset, it is necessary to use all the DMRS data of the two time slots on the entire channel bandwidth The subcarriers are all cross-correlated, and the large amount of calculation of the estimation algorithm will affect the real-time performance of system information transmission

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