Design and Performance of a Novel Interference-Free GFDM Transceiver With Dual Filter

Abstract

Generalized frequency division multiplexing (GFDM) as a sub-carrier filtered scheme can flexibly handle various different application scenarios of the fifth-generation system. However, due to the intrinsic self-interference resulting from the filter, the channel estimation becomes very hard, particularly when GFDM works with a multi-input multi-output (MIMO) system. In this paper, a new GFDM-dual filter (GFDM-DF) transmission scheme is proposed, which can guarantee the orthogonality of sub-carriers, so that the intrinsic self-interference can be eliminated. We first divide information symbols into odd-numbered and even-numbered sub-carrier symbols. Then, the orthogonality conditions for GFDM-DF are derived. According to the orthogonality conditions, we choose two different filters for odd-numbered and even-numbered sub-carriers. The signal-to-interference ratio of either the conventional GFDM or GFDM-DF is also evaluated. Moreover, based on the characteristics of the receiving matrix, we further design a low-complexity GFDM-DF receiver. Numerical results show that GFDM-DF can work well with the channel estimation and the MIMO system and its performance is better than that of the conventional GFDM system.