Comb pilot channel estimation and equalization device and method of OFDM system

Abstract

The invention discloses a comb pilot channel estimation and equalization device and method for an OFDM system, and the device comprises: an input buffer unit which is used for receiving and buffering effective input data of an OFDM signal; a pilot frequency storage unit which is used for storing a local initial pilot frequency symbol; a channel estimation unit which is used for performing pilot channel response estimation; an IFFT calculation unit which is used for carrying out IFFT operation to obtain a wireless channel time domain impulse response; a middle cache unit which is used for caching a plurality of first data of the time domain impulse response; a data preprocessing unit which is used for preprocessing a plurality of first data of the time domain impulse response; an FFT calculation unit which is used for estimating a frequency domain channel response by using a plurality of pre-processed data; a data balancing unit which is used for carrying out channel balancing; and a output cache unit which is used for caching and outputting the channel equalization result. According to the comb pilot channel estimation and equalization device and method of the OFDM system, the calculation complexity of channel equalization can be reduced, the calculation time delay is shortened, and the equalization precision is improved.

Description

technical field [0001] The invention relates to the technical field of communication engineering, in particular to a comb-shaped pilot channel estimation and equalization device and method for an OFDM system. Background technique [0002] Orthogonal Frequency Division Multiplexing (OFDM) is a multi-carrier modulation technology widely used in the field of mobile communications, which has high spectrum utilization and can resist multipath interference and wireless channel fading. At the sending end of the OFDM system, the information bits are mapped to QAM (Quadrature Amplitude Modulation) or PSK (phase-shift keying) symbols after encoding and interleaving. After inserting pilots according to certain pilot insertion rules, IFFT (Inverse Fast Fourier Transform , inverse fast Fourier transform) operation and adding a cyclic prefix (Cyclic Prefix, CP) before sending. When the signal arrives at the receiving end through the wireless channel, the signal with the cyclic prefix rem...

AI Technical Summary

Problems solved by technology

In addition, when the OFDM signal contains guard subcarriers, the current method only fills the guard symbols on the guard subcarriers without adding pilot symbols. At this time, the comb-like pilot symbols are not evenly distributed in the entire signal frequency band, which will lead to channel Impulse response energy leaks, which affects channel estimation and equalization accuracy

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