Abstract
In this paper we study the effect of multipath propagation on the performance of the forward link of a CDMA cellular system. We assume that RAKE receivers are used by the mobile terminals to receive the multipath signals and derive signal-to-noise ratios (SNR) for the RAKE receiver output for both orthogonal and non-orthogonal spreading sequences. These SNR expressions are evaluated using real impulse response measurement data obtained in the city of Toronto and comparisons are made between urban and suburban environments. We have found that even though multipath propagation tends to destroy the orthogonality of signals in an orthogonal CDMA system, the system with orthogonal CDMA codes still performs significantly better than a system utilizing random spreading codes in realistic multipath propagation environments.
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This work was supported in part by Bell Mobility Cellular and in part by the Information Technology Research Center of Ontario (ITRC).
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DaSilva, V.M., Sousa, E.S. & Jovanović, V. Effect of multipath propagation on the forward link of a CDMA cellular system. Wireless Pers Commun 1, 33–41 (1994). https://doi.org/10.1007/BF01098503
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DOI: https://doi.org/10.1007/BF01098503