Channel estimation and symbol detection method based on orthogonal time-frequency-space joint

Abstract

The invention discloses a channel estimation and symbol detection method based on orthogonal time-frequency-space joint, and the method comprises the following steps: 1, pilot symbol placement: building a mathematical model according to the relation between the input and output of an MIMO-OTFS system, and converting a channel estimation problem into a sparse signal reconstruction problem through the analysis of the mathematical model; 2, channel estimation: at a receiving end, pre-processing the signal to obtain a time delay-Doppler domain symbol; 3, symbol detection: at a receiving end, performing symbol detection according to the channel parameters obtained in the channel estimation step; 4, iterative feedback. The method has the advantages that the joint channel estimation and symbol detection method under the multi-input multi-output orthogonal time-frequency-space system is provided on the basis of the idea of iterative joint, the system performance can be improved through continuous feedback iteration, the symbol index set with the probability lower than the threshold value is detected again, and combined iterative detection of signal detection and channel estimation is formed to improve the system performance.

Description

technical field [0001] The invention belongs to the technical field of wireless communication in high mobility scenarios, and in particular relates to a joint channel estimation and symbol detection method based on a Multiple Input Multiple Output Orthogonal Time-Frequency Space (MIMO-OTFS) modulation system. Background technique [0002] At present, the modulation method adopted by the existing 5G communication technology is the Orthogonal Frequency Division Multiplexing (OFDM) scheme, which is very sensitive to frequency offset, and high-speed motion will generate a high Doppler frequency shift, which will cause carrier waves. Inter-Carrier Interference (ICI), so that the orthogonality between sub-carriers is destroyed, so the system performance is greatly reduced. In recent years, Ronny Hadani et al. proposed an Orthogonal Time-Frequency-Space (OTFS) modulation scheme, which has significant performance advantages over OFDM in dual-selective fading channels, especially in ...

AI Technical Summary

Problems solved by technology

Although the linear signal equalization scheme reduces the computational complexity, it also has the disadvantage of low system performance

Nonlinear signal detection schemes use the relationship between the transceiver and the optimal solution through iterative thinking, including message passing, variational Bayesian, and feedback equalization. These schemes greatly improve system performance, but iterative Its computational complexity is also very high

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