Summary
International Conference on Emerging Technologies for Communications
2022
Session Number:O2
Session:
Number:O2-5
Gradient Descent Direction Random Walk MIMO Detection using Intermediate Search Point
Naoki Ito, Yukitoshi Sanada,
pp.-
Publication Date:2022/11/29
Online ISSN:2188-5079
Summary:
In this paper, multi-input multi-output (MIMO) signal detection with random walk along a gradient descent direction using an intermediate search point is presented. As one of low complexity MIMO signal detection schemes, a gradient descent algorithm with Metropolis-Hastings (MH) methods has been proposed. Random walk along a gradient descent direction speeds up the MH based search using the gradient of a least-squares cost function. However, a gradient vector may be discarded through QAM constellation quantization in some cases. For further performance improvement, this paper proposes an improved search scheme in which the gradient vector is kept to generate an intermediate search point. The performance of the proposed scheme improves with higher order modulation symbols as compared with that of a conventional scheme. Numerical results obtained through computer simulation show that a bit error rate (BER) performance improves by 5dB at a BER of 10^-3 for 64QAM symbols in a 16 × 16 MIMO system.