Time-Multiplexed Training for Time-Selective Channels

Pilot-assisted channel estimation is considered in this letter, where the channel is assumed to be time-selective and can be accurately fit by a basis expansion model. The position and power of the pilots are crucial to the mean square error of the channel estimator. In this paper, we present nonlinear integer programming algorithms to optimize the position and power of the pilots. In comparison with the traditional equi-distant/powered pilot structure, the solution obtained from the proposed algorithms yields a better performance.