Title :
An efficient ungerboeck type MAP receiver for multi-user channel with M-ary quasi orthogonal signaling
Author :
Guvensen, G.M. ; Tanik, Yalcin ; Yilmaz, Ayhan Ozan
Author_Institution :
Elektrik ve Elektron. Muhendisligi Bolumu, Orta Dogu Teknik Univ., Ankara, Turkey
Abstract :
In this paper, a high performance MAP receiver with significantly reduced complexity is proposed for multiple-access channel with M-ary quasi orthogonal signaling. The proposed architecture operates on the channel and code matched filters (MF) belonging to each users signaling waveforms. The proposed MAP receiver is based on the factor graph (FG) obtained by using the equivalent channel model, and it operates on forward and backward directions along signaling intervals iteratively. Also, it is substantiated with bidirectional decision feedback (BDF) in order to limit the number of states used by each user. This Ungerboeck type MAP receiver, where Sum-Product Algorithm (SPA) with the support of RSSE, without need for whitening filter shows a very close performance to matched filter bound (MFB) at significantly reduced complexity for multipath channels with large delay spread and number of users.
Keywords :
matched filters; multiuser channels; radio receivers; FG; M-ary quasi orthogonal signaling; MF; MFB; RSSE; SPA; channel filters; code matched filters; complexity reduction; factor graph; matched filter bound; multiple-access channel; multiuser channel; sum-product algorithm; ungerboeck type MAP receiver; user signaling waveform; whitening filter; Bit error rate; Channel estimation; Complexity theory; Maximum likelihood estimation; Receivers; Sum product algorithm; Equalization; MAP; Multiple-access channel; SPA; Ungerboeck; reduced state sequence estimation;
Conference_Titel :
Signal Processing and Communications Applications Conference (SIU), 2013 21st
Conference_Location :
Haspolat
Print_ISBN :
978-1-4673-5562-9
Electronic_ISBN :
978-1-4673-5561-2
DOI :
10.1109/SIU.2013.6531279