Analysis and design of pilot-symbol-assisted codes, for the noncoherent AWGN channel, using density evolution

Pilot-symbol-assisted transmission of coded data over the block independent noncoherent AWGN channel is considered in this paper. Several iterative receivers are proposed and their performance is analyzed using density evolution. Upper and lower performance bounds are derived for the receiver based on the sum-product algorithm, and the optimal allocation of power to the pilots and coded bits is investigated. It is discovered that the optimal power allocation affects considerably the achievable performance, and depends highly on the phase dynamics. These results are verified by simulating practical codes and iterative receivers.