Mitigating the Degradation Effects of Fading Channels
نویسنده
چکیده
This article emphasizes so-called Rayleigh fading, primarily in the UHF band, that affects mobile systems such as cellular and personal communication systems (PCS). The major elements that contribute to fading and their degradation effects in a communication channel are briefly summarized. Emphasis is then placed on methods for mitigating the degradation. Two examples of specific mitigation techniques are examined: the Viterbi equalizer implemented in the Global System for Mobile (GSM) Communications, and the Rake receiver used in CDMA systems built to meet Interim Standard-95 (IS-95).
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