Blind Estimation of Sparse Simo Channels: Quadratic Vs. Linear Constraints
稀疏Simo信道的盲估计：二次约束与线性约束
疎なSimoチャネルのブラインド推定：2次対線形制約
희소 Simo 채널 의 블라인드 평가:2 차 제약 과 선형 제약
Estimación ciega de canales Simo escasos: restricciones cuadráticas y lineales
Blind Estimation of sparse Simo Channel: Quadratic and Linear Constraints
оценка слепоты на редком канале Симо: вторичное ограничение и линейное ограничение
¹ PRISME Laboratory, University of Orléans, Orléans, France
² Mathematical and Algorithmic Sciences Lab, France Research Center, Huawei Technologies Co. Ltd., Boulogne-Billancourt, France
2021 IEEE Statistical Signal Processing Workshop (SSP), 19 August 2021
Abstract
Blind multichannel estimation is classically done considering one of two constraints on the channel coefficients: (i) a quadratic constraint (i.e., unit-norm), or (ii) a linear constraint (i.e., fixed value for a particular coefficient). These constraints serve to remove the indeterminacy of the solution inherent to this estimation problem.
In this paper, we investigate the adequacy of both constraints in the particular case of sparse channels. For this purpose, we first conduct a Cramér-Rao Bound (CRB)-based performance comparison, then we support the obtained results with simulation experiments using a subspace method. The obtained results indicate that, contrary to common practice, the linear constraint should be favored over the quadratic constraint for the blind estimation of sparse channels.
