Performance of path-time codes for end-to-end transmission in ad hoc multihop networks

In this paper, we study the performance of the recently proposed class of path-time codes (PTCs), which exploit time and path diversity to increase the reliability of end-to-end transmission in ad hoc multihop networks. Using the central limit theorem, we prove that PTCs reshape the statistics of a relay path including multiple cascaded links. In particular, as the number K of relay paths becomes large, the cascaded channel statistic is transformed from K-product Rayleigh to Rayleigh. This is numerically demonstrated and analytically verified by using the concept of 'amount of fading' (AF). Our results show that, by using PTCs, the end-to-end error-rate performance can be boosted in addition to the diversity and coding gains.