A method and device for estimating frequency offset based on cp

Abstract

The embodiment of the invention discloses a frequency offset estimation method based on CP. The method comprises the following steps: sampling a time domain to extract a CP information sequence of a symbol and a second information sequence, positioned at the tail of the symbol and corresponding to the CP information sequence, of the symbol; respectively filling zero for the CP information sequence and the second information sequence so as to enable the length of each information sequence after filling zero to be the length of one symbol; converting the CP information sequence and the second information sequence after filling zero into a frequency domain to obtain a CP information sequence frequency spectrum and a second information sequence frequency spectrum; spreading and inhibiting the CP information sequence frequency spectrum and the second information sequence frequency spectrum to obtain a revised CP information sequence frequency spectrum and a revised second information sequence frequency spectrum; and estimating frequency offset according to the revised CP information sequence frequency spectrum and the revised second information sequence frequency spectrum. The embodiment of the invention further discloses a frequency offset estimation device based on CP. The method and the device are conducive to estimating more accurate frequency offset.

Description

technical field [0001] The present application relates to the field of communication technology, in particular to a CP (Cyclic Prefix)-based frequency offset estimation method and a device thereof. Background technique [0002] OFDM (Orthogonal Frequency Division Multiplexing, Orthogonal Frequency Division Multiplexing) channel bandwidth is divided into overlapping but orthogonal non-frequency selective narrowband channels, which greatly improves spectrum utilization and reduces receiver implementation complexity . But on the other hand, if the strict orthogonality condition is destroyed, it will seriously affect the orthogonality between subcarriers, cause subcarrier leakage, and cause serious inter-carrier interference. Finally, there may be a floor effect, that is, regardless of the increase No amount of transmit power can improve channel performance. However, in practical applications, there are many factors that destroy the orthogonality of the OFDM channel bandwidth,...

AI Technical Summary

Problems solved by technology

[0016] Although the above method can estimate the estimated value of the frequency offset, due to the "window effect", that is, operations such as zero padding and Fourier transform to obtain frequency domain information will cause spectrum expansion, so that the current UE is affected by frequency offset estimation. Due to the interference of adjacent UEs, the frequency offset estimation will have errors, especially when the UE bandwidth is small, the frequency offset estimation will have a large error

Images