Carrier synchronization method in UFMC system

Abstract

The invention relates to a carrier synchronization method in a UFMC system, comprising the following steps: first, generating two sets of orthogonal codes at a sender, inserting the orthogonal codes as pilot sequences into original data, and modulating, filtering and sending the original data through UFMC; then, performing time-domain zero filling and 2N-FFT transform at a receiver, extracting data on even bands, sending the data to a filter matching the sender, getting the estimated value of data information using a zero forcing equalizer, extracting pilot signals and calculating the correlation between the two sets of pilot signals, and minimizing the correlation to achieve UFMC system carrier frequency synchronization; and finally, using an iterative algorithm to improve the accuracy of frequency offset estimation. According to the invention, the carrier frequency offset of the system is estimated by inserting a pilot frequency into each sub band of UFMC, so good properties of the UFMC system are maintained, and the accuracy and stability of frequency offset estimation are improved through iteration. Therefore, the bit error performance of the system is enhanced, the quality of communication is improved, and the design complexity of the filter in the UFMC system is reduced to a certain extent.

Description

technical field [0001] The invention belongs to the technical field of wireless communication, and relates to a carrier synchronization method in a UFMC system. Background technique [0002] As a typical representative of multi-carrier technology, OFDM technology has been widely used in 4G. However, the following shortcomings of OFDM make it difficult to meet the needs of new scenarios. Firstly, each sub-carrier must be synchronized to maintain orthogonality, and the cost of synchronization will be unbearable when there are a large number of sensor nodes in the "wireless broadband" topic; secondly, it uses a square wave as the baseband waveform, and the carrier sidelobe is relatively large Finally, the CP length used is only related to the wireless channel, and the CP will cause a lot of waste of wireless resources when short frames are frequently transmitted. Therefore, Orthogonal Frequency Division Multiplexing (OFDM) may no longer be the best choice in 5G scenarios, and ...

AI Technical Summary

Problems solved by technology

It has the following characteristics: a) supports segmented spectrum communication; b) has lower out-of-band leakage compared with OFDM; c) has higher robustness to time-frequency offset and inter-carrier interference; d) due to The use of loose time-frequency calibration reduces signaling overhead, which also introduces many new options for access; e) The key lies in the design of the filter, which has a certain complexity

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