Title
Widely linear equalization and blind channel identification for interference-contaminated multicarrier systems
Abstract
This work addresses the problem of designing efficient detection techniques for multicarrier transmission systems operating in the presence of narrowband interference (NBI). In this case, conventional linear receivers, such as the zero-forcing (ZF) or the minimum-mean square error (MMSE) ones, usually perform poorly since they are not capable of suppressing satisfactorily the NBI. To synthesize interference-resistant detection algorithms, we resort to widely linear (WL) filtering, which allows one to exploit the noncircularity property of the desired signal constellation by jointly processing the received signal and its complex-conjugate version. In particular, we synthesize new WL-ZF receivers for multicarrier systems, which mitigate, in the minimum output-energy (MOE) sense, the NBI contribution at the receiver output, without requiring knowledge of the NBI statistics. By exploiting the noncircularity property, we also propose a new subspace-based blind channel identification algorithm and derive the channel identifiability condition. Blind identification can be performed satisfactorily also in the presence of NBI, requiring only an approximate rank determination of the NBI autocorrelation matrix. The performance analysis shows that the proposed MOE WL-ZF receiver, even when implemented blindly, assures a substantial improvement over the conventional linear ZF and MMSE ones, particularly when the NBI bandwidth is very small in comparison with the intercarrier spacing and the NBI is not exactly located on a subcarrier.
Year
DOI
Venue
2005
10.1109/TSP.2004.842198
IEEE Transactions on Signal Processing
Keywords
Field
DocType
blind identification,autocorrelation matrix,conventional linear receiver,widely linear equalization,minimum output-energy,noncircularity property,radiofrequency interference,nbi autocorrelation matrix,nbi contribution,minimum-mean square error method,narrowband interference,efficient detection technique,conventional linear zf,nbi statistic,interference-contaminated multicarrier system,telecommunication channels,least mean squares methods,signal detection technique,blind channel identification,widely linear filtering,filtering theory,radio receivers,equalisers,interference suppression,channel identifiability condition,zero-forcing method,nbi bandwidth,linear equalization,statistics,minimum mean square error,interference,filtering,indexing terms,constellation diagram,zero forcing,signal processing
Subcarrier,Signal processing,Narrowband,Equalization (audio),Control theory,Autocorrelation matrix,Filter (signal processing),Bandwidth (signal processing),Constellation diagram,Mathematics
Journal
Volume
Issue
ISSN
53
3
1053-587X
Citations 
PageRank 
References 
35
1.38
28
Authors
4
Name
Order
Citations
PageRank
D. Darsena1764.64
G. Gelli221415.91
Luigi Paura3106676.14
F. Verde41338.40