Higher-order spectral analysis of complex signals
Signal Processing - Special section: Distributed source coding
Code combination for blind channel estimation in general MIMO-STBC systems
EURASIP Journal on Advances in Signal Processing
A numerical solution for multichannel detection
IEEE Transactions on Communications
IEEE Transactions on Information Theory
Widely linear estimation algorithms for second-order stationary signals
IEEE Transactions on Signal Processing
Analysis of receiver algorithms for LTE SC-FDMA based uplink MIMO systems
IEEE Transactions on Wireless Communications
Properness and widely linear processing of quaternion random vectors
IEEE Transactions on Information Theory
On the asymptotic distribution of GLR for impropriety of complex signals
Signal Processing
Widely linear prediction for transfer function models based on the infinite past
Computational Statistics & Data Analysis
| Hi-index | 754.96 |
Nonstationary complex random signals are in general improper (not circularly symmetric), which means that their complementary covariance is nonzero. Since the Karhunen-Loeve (K-L) expansion in its known form is only valid for proper processes, we derive the improper version of this expansion. It produces two sets of eigenvalues and improper observable coordinates. We then use the K-L expansion to solve the problems of detection and estimation of improper complex random signals in additive white Gaussian noise. We derive a general result comparing the performance of conventional processing, which ignores complementary covariances, with processing that takes these into account. In particular, for the detection and estimation problems considered, we find that the performance gain, as measured by deflection and mean-squared error (MSE), respectively, can be as large as a factor of 2. In a communications example, we show how this finding generalizes the result that coherent processing enjoys a 3-dB gain over noncoherent processing.