A parallel processing approach to filterbank multicarrier MIMO transmission under strong frequency selectivity

Abstract

The problem of MIMO transmission using filterbank multicarrier (FBMC) modulations in strong frequency selective channels is considered. A novel architecture for the implementation of MIMO precoders and linear receivers is derived, which consists of multiple parallel stages that are combined at the per-subcarrier level. Each of these stages is constructed like a classical FBMC modulator/demodulator, using the successive derivatives of the prototype pulse instead of the original one. The performance of the proposed architecture is theoretically characterized in terms of the residual distortion power at the output of the receiver, assuming an asymptotically large number of subcarriers. Results demonstrate the effectiveness of the proposed architecture in MIMO channels with severe frequency selectivity.Index Terms-Filterbank Multicarrier, MIMO, FBMC/OQAM, spatial multiplexing.

Optimal zero forcing precoder and decoder design for multi-user MIMO FBMC under strong channel selectivity

“…2 based on a simple one tap per-subcarrier precoding or decoding matrix. However, we do not make the assumption that the channel is frequency flat at the subcarrier level and we characterize (and simplify) the expression of the mean squared error (MSE) based on the distortion approximation derived in [10]. Minimizing the MSE formula, the optimal ZF precoding and decoding matrices are found, taking into account the channel frequency selectivity.…”

“…Under the previous assumptions and for a large number of subcarriers, an expression of the asymptotic distortion was given in [10] for the case of different pulses at transmitter and receiver sides. In the more specific case considered here, the total MSE at subcarrier k can be written as follows…”

“…On the other hand, [9] proposes a multitap filtering solution at both transmit and receive sides. The work originally devised for the SISO case in [3] and later extended for the MIMO case in [10] proposes instead a parallel multi-stage processing architecture at both sides of the communication link. One should The research reported herein was partly funded by Fonds pour la Formationà la Recherche dans l'Industrie et dans l'Agriculture (F.R.I.A.)…”

Channel Equalisation of a MIMO FBMC/OQAM System Using a Polynomial Matrix Pseudo-Inverse

“…Different from OFDM, FBMC creates subcarriers that retain at least some frequencyselectivity. Even though recent practical measurements indicate that for a well-synchronised FBMC system, single tap equalisers may be sufficient [14], generally significant dispersion has to be considered [3], [12], if not through long channel impulse response then through insufficient timing synchronisation of the receiver [13]. As a result, significant inter-symbol interference (ISI) arises.…”

“…This is generally seen as a significant problem, and substantial efforts have been undertaken to combat these interference terms -see e.g. early works in [7], or more recently in [3], [12] or the review in [15]. The majority of these publications has targetted the joint design of precoders and equalisers, which can enable significant benefits if the channel is know to both receiver and transmitter.…”