9 research outputs found
Multichannel receivers from ofdm and tdma in mobile communications
This paper addresses the use of multichannel receivers for blind equalization in TDMA under frequency selective channels and OFDM systems in frequency flat fading channels. A new criteria is proposed for blind equalization of finite length mobile channels.Peer ReviewedPostprint (published version
Diversity techniques for blind channel equalization in mobile communications
A blind algorithm for channel distortion compensation is presented which can be employed in spatial or temporal diversity receivers. The proposed technique can be used in frequency selective and frequency flat fading mobile channels, using burst transmission schemes in the first case and OFDM modulation in the second one. The algorithm is base on a deterministic criteria and is suited for estimation when short sets of data are available.Peer ReviewedPostprint (published version
Blind channel identification based on second-order statistics: a frequency-domain approach
In this communication, necessary and sufficient conditions are presented for the unique blind identification of possibly nonminimum phase channels driven by cyclostationary processes. Using a frequency domain formulation, it is first shown that a channel can be identified by the second-order statistics of the observation if and only if the channel transfer function does not have special uniformly spaced zeros. This condition leads to several necessary and sufficient conditions on the observation spectra and the channel impulse response. Based on the frequency-domain formulation, a new identification algorithm is proposed
Enhanced Transmission and Receiver Diversity in Orthogonal Frequency Division Multiplex Systems using Blind Channel Estimation
This paper deals with the blind channel estimation technique in OFDM system with receiver diversity to analyze the bit error rate with respect to the number of symbols. The paper clearly brings out the advantage that is being offered by the use of Blind channel estimation technique in terms of SNR requirements. Also a comparative study has been made for the analysis of BER variation with the amount i.e. number of symbols being transmitted. The work also explores the possibility of obtaining an optimum value of number of receivers that may lead to desired BER for threshold value of SNR in an OFDM system
Generalized Signal Richness Preservation Problem and Vandermonde-Form Preserving Matrices
In this paper, a theoretical problem arising in digital communications, namely the generalized signal richness preservation problem, is addressed and studied. In order to solve the problem, a special class of square matrices, namely the "Vandermonde-form preserving" (VFP) matrices, is introduced and found to be highly relevant to the problem. Several properties of VFP matrices are studied in detail. The necessary and sufficient conditions of the problem have been found, and a systematic proof is also presented
Diversity techniques for blind channel equalization in mobile communications
Cet article traite de l'Ă©galisation aveugle de canaux mobiles qui sont soit sĂ©lectifs en frĂ©quence soit multiplicatifs. L'algorithme proposĂ© peut-ĂȘtre utilisĂ© pour compenser la distorsion de canaux ĂĄ changements rapides oĂč un ensemble restreint de donnĂ©es est disponible pour estimer les coefficients de l'Ă©galiseur