  Future wireless communication systems are demanding a more flexible physical
layer. GFDM is a block filtered multicarrier modulation scheme proposed to add
multiple degrees of freedom and cover other waveforms in a single framework. In
this paper, GFDM modulation and demodulation will be presented as a
frequency-domain circular convolution, allowing for a reduction of the
implementation complexity when MF, ZF and MMSE filters are employed in the
inner and outer receiver operation. Also, precoding is introduced to further
increase GFDM flexibility, addressing a wider set of applications.
