Low complexity BEM channel estimation method using fast Fourier transform

Abstract

The invention belongs to the technical field of digital information transmission and discloses a low complexity BEM channel estimation method using fast Fourier transform, which comprises the following steps: generating a basis vector and a corresponding sum vector according to a complex exponential basis expansion model; generating a solution matrix A for solving a base coefficient via a known pilot symbol according to a basis expansion model signal expression; obtaining a basis coefficient vector via the received pilot symbol and the solution matrix A; performing the fast Fourier transform on the basis coefficient vector, and obtaining a frequency domain channel response value with the sum vector. The method in the invention has the advantages of high estimation precision and low computational complexity, and is suitable for an SC-FDMA or OFDM system with fixed block pilots. According to the method in the invention, based on the basis expansion model, the complex matrix operation issimplified into the fast Fourier transform by using the time-frequency domain transform characteristic of the channel response, which simplifies the time-frequency domain conversion formula in the BEMchannel estimation algorithm and greatly reduces the computational complexity of the BEM algorithm.

Description

technical field [0001] The invention belongs to the technical field of digital information transmission, in particular to a low-complexity BEM channel estimation method using fast Fourier transform. Background technique [0002] At present, the existing technologies commonly used in the industry are as follows: With the continuous development of technology, the speed of transportation is constantly increasing. The new generation of the fastest offshore unmanned boat "Tianxing No. 1" can reach a maximum speed of 92.6km / h, and the drone can reach 280km / h. The high-speed railway operated in my country can reach a maximum speed of 350km / h. The speed can reach 432km / h. The high-speed movement of the receiving end of the communication system will seriously affect the transmission performance of the communication system, which poses a huge challenge to the high-quality transmission of the communication system. In the high-speed mobile environment, the wireless channel becomes a f...

AI Technical Summary

Problems solved by technology

However, these traditional BEM algorithms involve frequency domain and time domain data processing, including a large number of matrix operations, and have high computational complexity. It is difficult to adopt them in actual hardware implementation, and the simplified algorithm must be considered

In "Fast Time-Varying Channel Estimation Method Based on Simplified Basis Extension Model", the transformation relationship between time domain and frequency domain of channel characteristics is used to simplify the transformation formula of channel response from time domain to frequency domain, and to estimate the received signal with lower complexity The channel response in the frequency domain can greatly reduce the computational complexity of the BEM algorithm. However, in the process of simplifying the time domain-frequency domain transformation formula, the algorithm approximates the time domain channel matrix as a Toeplitz circulant matrix, and the performance is slightly lost. High-dimensional matrix operations are used in the transformation formula, and the computational complexity is still high

[0003] In summary, the problems in the prior art are: Although the BEM algorithm shows good performance in dynamic multipath channels, its computational complexity is too high, and a large number of high-dimensional matrix operations will bring huge resource occupation and long delay, which is difficult to apply in practical systems

In order to solve the above technical problems, people are constantly looking for a more simplified BEM algorithm, and want to apply it to the actual system In order to improve the information transmission performance of the communication system, although the simplified BEM algorithm is proposed in the existing related achievements, its complexity Complexity is still high

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