Frequency-Domain Message-Passing Receiver for Joint Channel Estimation and Data Detection in Single-Carrier MIMO Underwater Systems

In this article, we propose a message-passing based, frequency domain iterative receiver for a single-carrier, multiple-input multiple-output (MIMO) underwater acoustic (UWA) communication systems. This algorithm is capable of jointly estimating the channel impulse response (CIR) and performing symbol detection. In each iteration, it utilizes the soft information of the data symbols to estimate the channel. Furthermore, a Bernoulli-Gaussian prior is introduced to effectively characterize the sparsity of the channel. This approach is particularly beneficial in addressing the challenges posed by the excessive number of CIR parameters required in long delay spread MIMO UWA channels. Additionally, the use of fast Fourier transform significantly reduces computational complexity. Simulation results substantiate the performance of the proposed algorithm.