A Receiving Algorithm Based on Iterative Channel Estimation in Filtered Multitone Modulation System

Abstract

The invention provides a receiving algorithm based on iterative channel estimation in an FMT system. An iterative method is adopted and the interference of data to a pilot frequency is estimated usinga result recovered in last iteration, thereby obtaining more accurate channel estimation and further reducing a system bit error rate; under the condition in which a spectrum utilization rate of theFMT system is not reduced, the interference of the data to the pilot frequency is estimated through iteration, and thus the accuracy of channel estimation is continuously improved and the system bit error rate is reduced; compared with other algorithms, the receiving algorithm does not need to use a block-type pilot frequency or perform zero padding between the pilot frequency and the data, so thespectrum waste is avoided and the spectrum utilization rate is improved; and meanwhile, the receiving algorithm replaces plenty of matrix inversion computations with FFT / IFFT, so that the computational complexity is reduced to a certain extent.

Description

technical field [0001] The invention relates to the field of digital wireless communication, in particular to a receiving algorithm based on iterative channel estimation and equalization, which is suitable for a filter multi-tone modulation (FMT) system. Background technique [0002] In the high-speed wireless communication environment, due to the influence of fading channels, it often leads to severe inter-symbol interference, which greatly limits the performance of the system. As we all know, the multi-carrier modulation technology divides the transmission channel into multiple parallel sub-channels, and the symbol duration in each sub-channel is extended, so that the fading experienced by each sub-channel is approximately flat fading. In addition, the multi-carrier modulation technology also has It has a series of advantages such as insensitivity to narrowband interference, flexible bandwidth expansion and support for multiple users. [0003] OFDM is a typical multi-carr...

AI Technical Summary

Problems solved by technology

However, OFDM has some inherent disadvantages: the orthogonality between sub-channels is easily destroyed during transmission, so strict carrier synchronization and timing synchronization are required to ensure system performance; a large amount of overhead (cyclic prefix, virtual carrier) is required to eliminate ISI and Reduce out-of-band radiation

The traditional equalization method needs to find the inverse matrix of the equivalent sub-channel convolution matrix, and then multiply it with the receiving vector to obtain the estimated value of the transmitted symbol. This method needs to solve M (N×N)-dimensional inverse matrix operations in total. When M and N are relatively large, the computational complexity will be large

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