Optimized time-shifted pilots for maritime massive MIMO communication systems

With the growing demand for mobile multimedia services in marine activities, maritime communication systems are impelled to provide higher data rates with limited radio resources. Massive multiple-input multiple-output (MIMO) is thus recognized as a promising technology in this case. However, pilot contamination leads to strong inter-cell interference and greatly degrades system performance. In this paper, we focus on the joint position-power optimization of time-shifted pilots in a maritime massive MIMO system. Based on large-scale channel fading information, we first propose an efficient user scheduling algorithm, and then optimize the pilot power under the average power constraint. Further, we optimize the positions and power of the pilots iteratively. Simulation results show that our proposed scheme achieves a considerable coordination gain in system performance in terms of spectral efficiency.