Summary: | 碩士 === 國立臺北科技大學 === 電腦通訊與控制研究所 === 89 === In the wireless communication research, the accurate fading channel model is necessary. The objective of thesis is to propose a fading channel model which could predict more suitable statistical properties of the fading channel. In general, traditional Markov Chains were used to describe environmental parameter variations, but this model cannot simulate the phenomenon of fast fading due to Doppler effect. Although Doppler effect can be simulated by the appropriate designed digital filter, that will lack to carry the information of slow fading about the environmental variations.
In this paper, the combination of Markov chain and digital filter is not only presented to describe the phenomenon of slow fading due to environmental variations, but also describe the phenomenon of fast fading due to Doppler effect. On the other hand, a lot papers only used Digital filter to simulate fast fading, but they can’t describe completely the variation of fast fading power. We use the parameter of Markov chain to modify and simulate fast fading power. The comparison on the statistics of PDF, CDF, LCR, between the measured and simulated signal show that the presented method is good agreement. In other hand, in order to estimate the bit error rate (BER) performance, we also deploy our channel simulator into a wireless communication system with the DPSK modulation scheme. The analysis also shows that our simulated result is better agreement with the measured result than other presented method.
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