Decoding Schemes for FBMC with Single-Delay STTC

Abstract

Orthogonally multiplexed Quadrature Amplitude Modulation (OQAM) with Filter-Bank-based MultiCarrier modulation (FBMC) is a multicarrier modulation scheme that can be considered an alternative to the conventional orthogonal frequency division multiplexing (OFDM) with cyclic prefix (CP) for transmission over multipath fading channels. However, as OQAM-based FBMC is based on real orthogonality, transmission over a complex-valued channel makes the decoding process more challenging compared to CP-OFDM case. Moreover, if we apply Multiple Input Multiple Output (MIMO) techniques to OQAM-based FBMC, the decoding schemes are different from the ones used in CP-OFDM. In this paper, we consider the combination of OQAM-based FBMC with single-delay Space-Time Trellis Coding (STTC). We extend the decoding process presented earlier in the case of N t = 2 transmit antennas to greater values of N t. Then, for N t ≥ 2, we make an analysis of the theoretical and simulation performance of ML and Viterbi decoding. Finally, to improve the performance of this method, we suggest an iterative decoding method. We show that the OQAM-based FBMC iterative decoding scheme can slightly outperform CP-OFDM.

A Survey on Multicarrier Communications: Prototype Filters, Lattice Structures, and Implementation Aspects

“…Similarly, in order to remove the imaginary parts at the receiver, a scheme, referred as FFT-FBMC, is proposed in [129] and applied to the multiple antenna systems. While imaginary parts are canceled for the case of single-delay spacetime trellis coding (STTC) with two transmit and one receive antennas in [130], later, this study is extended to multiple transmit antennas in [131] by proposing an iterative decoding approach. All in all, there still needs to be more studies on the application of multiple antennas to lattice staggering approaches under practical implementation scenarios.…”