アンダーサンプリングを用いたQAM信号評価法の提案

抄録

This paper describes a QAM signal evaluation method in a radio communication evaluation system based on under-sampling. Although frequency elements generated by quadrature demodulation can be calculated using QAM symbols on a constellation, this technique requires a symbol synchronous trigger. Our proposed method has a software triggering technique that can extract the symbols regardless of the frequency difference. Numerical simulation with 16QAM showed good synchronization between the trigger and the measured waveforms. In addition, the results of demonstration experiment using 16QAM with carrier frequency of 28 GHz showed the practicality of the proposed method by drawing an eye pattern and a constellation. In conclusion, we show the possibility of high-resolution and low-cost measurement in QAM signals with mmWave carrier frequency.