A novel MIMO-GFDM receiver for next generation communication

Orthogonal frequency-division multiplexing is not suitable for fifth-generation applications such as machine-type communication, tactile internet, and internet of things. Generalized frequency-division multiplexing (GFDM) is presented to address these requirements on the basis of the pulse-shaping filter architecture, which makes GFDM have lower out-of-band emission and relatively less cyclic prefix and a become candidate for fifth-generation systems. Because of the filter architecture, the subcarrier is nonorthogonal, which leads to serious intercarrier interference and is sensitive to carrier frequency offset (CFO). For reducing the intercarrier interference, we propose a 2-path conjugate transmission scheme in the transmitter, and an adaptive receiver based on the modified phase rotated conjugate cancellation scheme is derived. By maximizing the carrier-to-interference ratio, we derive the optimal phase rotation and present an adaptive normalized block least mean squared algorithm to search the ideal result. With the proposed adaptive receiver, the CFO variation due to mismatch oscillator frequency and channel effect can be tracked effectively without feeding back the estimated information to the transmitter. In this paper, we propose a novel receiver with channel equalization and CFO compensation for multiple-input-multiple-output-GFDM systems in time-varying channels. So far, no related research works exist. In the simulations, we compare the proposed receiver with several existing schemes in different time-varying channels and modulations. The proposed scheme outperforms the existing schemes.