A Practical Dirty Paper Coding Applicable for Broadcast Channel

Abstract

In this paper, we present a practical dirty paper coding scheme using trellis coded modulation for the dirty paper channel $Y=X+S+W,$ $\mathbb{E}\{X^2\} \leq P$, where $W$ is white Gaussian noise with power $\sigma_w ^2$, $P$ is the average transmit power and $S$ is the Gaussian interference with power $\sigma_s ^2$ that is non-causally known at the transmitter. We ensure that the dirt in our scheme remains distinguishable to the receiver and thus, our designed scheme is applicable to broadcast channel. Following Costa's idea, we recognize the criteria that the transmit signal must be as orthogonal to the dirt as possible. Finite constellation codes are constructed using trellis coded modulation and by using a Viterbi algorithm at the encoder so that the code satisfies the design criteria and simulation results are presented with codes constructed via trellis coded modulation using QAM signal sets to illustrate our results.