The Application of μu-Law Companding to the WiMax IEEE802.16e Down-Link PUSC

This paper presents a simulation investigation of the PSD, BER and PAPR for the IEEE802.16a mobile WiMax standard Down Link PUSC when μ-law companding is applied. Results are presented for μ values of 0.1, 1, 3, 10, 30, 100, 255 and 1000, for QPSK, 16-QAM and 64-QAM modulation, and for both fixed pilot and randomly phased BPSK pilot situations. The simulations demonstrate that significant BER and PAPR improvement can result through μ-Law companding but at the cost of increased transmitter power and increased PSD frequency splatter. Optimized μ settings for best BER performance are determined along with the corresponding PAPR level probability curves. The simulation results also allow decisions to be taken regarding the level of companding applied and the compromise desired between any required BER and PAPR levels.