A method and device for correcting uplink frequency deviation

Abstract

The present invention provides a method and device for correcting uplink frequency deviation. The method includes: presetting the corresponding relationship between CP phase difference and quantization value, wherein the CP phase difference is the phase of the OFDM symbol estimated according to the CP value of the OFDM symbol Each CP phase difference corresponds to a quantized value; S1: Calculate the CP phase difference of the current terminal; S2: Find the CP quantized value according to the corresponding relationship, where the CP quantized value is the CP phase difference of the current terminal The corresponding quantization value in the corresponding relationship; S3: Utilize two columns of pilots in an uplink subframe to estimate the phase difference of the OFDM symbol, and obtain the phase difference estimation value of the current terminal; S4: According to the CP quantization value, the phase difference The estimated value corrects the estimated value of the phase difference to obtain a corrected phase difference; S5: Perform phase compensation on the received data of the current terminal according to the corrected phase difference. Through the method and device adopted in the present invention, the complexity of correcting the uplink frequency deviation can be reduced.

Description

technical field [0001] The present invention relates to the technical field of communications, in particular to a method and device for correcting uplink frequency deviation. Background technique [0002] In the communication system, the high-speed movement of the terminal will cause Doppler frequency shift. For example, if the terminal is traveling at a speed of 300km / h and the carrier frequency is 2.6GHz, the maximum Doppler frequency shift generated is about 722Hz. In the uplink, the Doppler frequency shift caused by the movement of the terminal will be at most twice the maximum Doppler frequency deviation, that is, the terminal is traveling at a speed of 300km / h, regardless of the downlink synchronization error condition Down, the uplink frequency deviation can reach up to 1444Hz. Under such frequency deviation conditions, if some measures are not taken, the uplink data cannot be received correctly. [0003] In the existing frequency offset estimation algorithms, some ...

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Problems solved by technology

Under such frequency deviation conditions, if some measures are not taken, the uplink data cannot be received correctly

[0003] In the existing frequency offset estimation algorithms, some use pilots to estimate the frequency offset. For example, in LTE, the phase difference between two columns of pilots in a subframe of PUSCH (Physical Uplink Shared Channel) is used to calculate the frequency offset. Perform frequency offset estimation. The maximum frequency offset that can be estimated by this method is around 1071Hz. If the uplink frequency offset exceeds this range, the uplink signal will be unreceivable

In high-speed situations such as high-speed rail, the speed of the terminal may reach or even exceed 300km / h. If the carrier frequency is 2.6GHz, considering that the downlink synchronization error is 0.01ppm, the uplink frequency deviation will reach 1444+260=1704Hz. The maximum frequency offset range that can be estimated by using the pilot is exceeded, and the data will not be received at this time

[0004] It can be seen from the above description that in the uplink frequency offset estimation method in the prior art, it is more complicated to correct the uplink frequency offset

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