  As a candidate waveform for next-generation wireless communications,
generalized frequency division multiplexing (GFDM) features several decent
properties which make it promising. In this paper, we systematically overview
the research about GFDM. We start with GFDM transceivers with their main
components, which consist of prototype filter design, low-complexity
transceiver implementation, and symbol detection algorithms. Then, we
investigate a couple of non-ideal issues of GFDM, including synchronization
issues, channel estimation, and in-phase/quadrature (I/Q) imbalance
compensation. Lastly, we study the applications of GFDM-based cognitive radio
and full-duplex radio which boast of a high spectral efficiency.
