Abstract: A low-complexity modulation and demodulation algorithm based on sparse matrix is proposed to address the issue of high complexity in generalized frequency division multiplexing (GFDM) systems, which restricts its ability to meet the requirements of various application scenarios in future communication systems. Firstly, the system model of GFDM is analyzed, presenting two different modulation structures. Subsequently, the sparsity of the frequency domain coefficients of the prototype filter is leveraged to make the modulation and demodulation matrices sparse in frequency domain using different Fourier transforms. By rearranging the sparse matrices, various block diagonal matrices can be constructed. Finally, the block diagonal matrix is used to modulate and demodulate the data vector transformed to frequency domain, which can effectively reduce the computational complexity of GFDM system. Simulation results demonstrate that both low-complexity algorithms achieve good complexity performance under different numbers of subcarriers, while showcasing the advantages of GFDM's flexible time-frequency structure.

Key words: new multicarrier technology, generalized frequency division multiplexing, complexity, sparse matrix