Summary: | 碩士 === 北台科學技術學院 === 機電整合研究所 === 93 === The effect of non-zero relative group delays and the phase incoherence on the received signal are investigated for linear array antennae. We find that the non-zero relative group delays among all the received signals from antenna elements do introduce inter-symbol interference (ISI), where the ISI level increases as the number of antenna elements and the CDMA chip rate increase. Regarding phase incoherence between the array receiver and the incoming RF signal, we find that a pure frequency difference has no effect at all. On the other hands, the phase difference has significant effect on the received BER, where the effect becomes severe when the phase difference is greater than p/3.
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