Method and device for determining maximum multipath time delay

Abstract

The invention discloses a method and a device for determining maximum multipath time delay, which belong to the technical field of communication and are used for solving the problem that in the prior art, the channel estimation has overlarge errors. The method for determining the maximum multipath time delay comprises the following steps: determining a time region channel estimated value of a channel; comparing the time region channel estimated value of the channel and the preset power threshold of a channel effective path, and determining the effective path with the maximum time delay in thechannel according to the comparison result; and determining the maximum multipath time delay of the channel by using the time delay corresponding to the effective path. The method and the device are used for determining the maximum multipath time delay of the channel so that the accuracy of the channel estimation can be improved by using the maximum multipath time delay determined by the method and the device so as to improve the system performance.

Description

Technical field [0001] The present invention relates to the field of communication technology, and in particular to a method, system and device for determining the maximum multipath delay τmax. Background technique [0002] In an Orthogonal Frequency Division Multiplex (OFDM, Orthogonal Frequency Division Multiplex) system, using a Minimum Mean Square Error (MMSE) algorithm can generally obtain a good channel estimation effect. [0003] The MMSE algorithm is a channel estimation algorithm that uses pilot frequency points. It obtains the channel estimation of other subcarriers after interpolation according to the frequency domain autocorrelation information of the channel. Therefore, when using the MMES algorithm, it is necessary to know the frequency domain autocorrelation matrix of the channel, and the frequency domain autocorrelation matrix of the channel and the channel's maximum multipath delay N τmax related. [0004] In order to completely eliminate inter-symbol interference (...

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Problems solved by technology

[0005] However, it can be found through simulation that the CP length of the system is directly used as the maximum multipath delay N of the channel in the prior art τmax The practice will lead to inaccurate channel estimation results, and sometimes there will be large errors, which will affect the demodulation performance of the system, resulting in greatly reduced system performance

[0006] To sum up, the prior art has no requirement for the maximum multipath delay N τmax Instead, it is directly replaced by the CP length, which leads to a large channel estimation error in the system, affects the demodulation performance of the system, and greatly reduces the system performance.

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