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Modulation technique, such as QAM and PSK may provide wireless communication with bandwidth efficiency. They each have their advantages, especially when it comes to BER performance over a wireless channel. They increase the performance of the bandwidth when used along with the OFDM. The FFT usually used in the OFDM system; however, it significantly increased the PAPR. DWT-based OFDM system can be implemented to solve this, and PTS technique can further improve it. This paper aims to do a simulation comparing QAM and PSK's BER performance. Both modulation technique will have the order of 4, 8, 16, 64, and 256.Additionally, the bit order will be Gray-mapped. The signal is implemented in DWT-based OFDM system with PTS technique through AWGN channel. The result shows that the performance of 4-QAM is similar to QPSK. Then, 8-QAM is slightly better than 8-PSK, and as the order gets higher, the QAM shows a much better performance than PSK. The constellation diagram of QAM shows that the distance between each combination is constant for any order. PSK has a smaller distance; thus, it is very rational for QAM to perform better than PSK for the higher-order as 16-QAM, 64-QAM, and 256-QAM. |
