Cooperative In-Home Power Line Communication: Analyses Based on a Measurement Campaign

This work focuses on analyses of cooperative protocols to enhance the performance of power line communication systems. Based on a measurement campaign and considering a sum power constraint, achievable data rates for amplify-and-forward (AF) and decode-and-forward (DF) protocols are analyzed. Similar investigations are performed for the maximum data rates attained using Hermitian-symmetric orthogonal frequency division multiplexing (HS-OFDM) together with equal gain combining (EGC), selection combining (SC) and maximal ratio combining (MRC) techniques. The influences of optimally and uniformly allocated transmission power and frequency bandwidth are are also analyzed and the efficiency of combination before and after equalization is compared. Results show that the relative distances among source, relay and destination nodes significantly impact system performance. Also, they reveal a range of total transmission power and bandwidth in which benefits can be verified. Among combining techniques, MRC and SC present similar results, but MRC offers a slightly better performance. In relation to computational complexity, SC is the most favorable. Maximum data rate analyses of HS-OFDM with frequency domain equalization based on zero forcing and minimum mean square error criteria show that the former scheme offers almost the same performance as the latter. Furthermore, it is shown that equalization after combination is more advantageous.