Performance Analysis of Momentum-Based Complex LMS Adaptive Filter for Non-circular Signals
摘要
The momentum-based complex least mean square (MCLMS) algorithm introduces an additional momentum term to improve the convergence speed and stability of the algorithm, with only a negligible increase in complexity. However, the standard MCLMS algorithm assumes that the signal is second-order circular (proper), meaning that its real and imaginary components are uncorrelated and have equal energy. Under this assumption, the information within the complementary statistics is lost. To address this issue, this work bridges momentum acceleration with improper signal processing by establishing the first theoretical framework for a noncircular MCLMS. Key innovations include: 1. A joint mean-square error (MSE) and complementary MSE (CMSE) analysis that incorporates the signal pseudocovariance; 2. An Approximate Uncorrelating Transform (AUT) that reduces the complexity of covariance diagonalization from