Orthogonal matching pursuit channel estimation method based on frequency response pre-interpolation

Abstract

The invention provides an orthogonal matching pursuit channel estimation method based on frequency response pre-interpolation. The method comprises the following steps: step 1, processing a received signal to obtain a channel frequency domain response at a subcarrier where a pilot frequency is located; step 2, selecting a local pre-interpolation or an overall pre-interpolation according to the performance of an interpolation algorithm, pre-interpolating the channel frequency domain response obtained in the step 1 to beta times of the original length, and completing path time delay estimation by using an OMP channel estimation algorithm based on IFFT; and step 3, outputting a path time delay estimation result. According to the method, the frequency response used in an OMP channel estimationalgorithm at a receiving end is pre-interpolated to be beta times of the original length by means of the interpolation algorithm and the like, so that the measurable maximum time delay value is increased to be beta times of the original time delay value. Pre-interpolation frequency response at the receiving end can replace insertion of excessive pilot frequency in transmitting OFDM signals, so that the information transmission rate and the time delay estimation range of a communication system can be ensured at the same time.

Description

technical field [0001] The invention relates to a method for increasing the estimable time delay range of Orthogonal Matching Pursuit (OMP), in particular to a frequency response pre-interpolation based Orthogonal Matching Pursuit (OMP) channel estimation method. Background technique [0002] In recent years, Orthogonal Frequency Division Multiplexing (OFDM) technology has been widely used in high-speed communication systems because of its high bandwidth utilization and low channel equalization complexity. In an actual OFDM communication system, the performance of the OFDM communication system is closely related to channel estimation, so the accuracy of channel delay estimation is very important. Most systems use coherent receivers, which makes the accuracy of time delay estimation in channel estimation variable. It is very important. [0003] Studies have shown that underwater acoustic channels usually have sparseness, that is, the energy of most channel coefficients is sm...

AI Technical Summary

Problems solved by technology

Based on the traditional OMP algorithm, this method proposes a continuous-time expression of the channel delay, which reduces the computational complexity to a certain extent, but does not pre-interpolate the frequency response input in the OMP algorithm. This method can estimate the maximum Latency still depends on the number of pilots in the transmitted signal

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