Abstract
We give a quadratic form expression of the mean squared multiple-access interference (MAI) averaged over relative time delays for chip-asynchronous DS/CDMA systems. A lower bound on the mean squared MAI is referred to as chip-asynchronous version of Welch bound, which depends on chip pulse shapes. Real analysis tells us that a pair of rectangular and sinc functions is one of Fourier transform and its inverse Fourier transform and vice versa. On the other hand, Gaussian pulses have the self-duality property. Gaussian chip pulses sacrifice inter-symbol interference, however, they give smaller mean squared MAI, as well as lower bit error rate, than the conventional Nyquist pulses.
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Jitsumatsu, Y., Kohda, T. (2006). Chip-Asynchronous Version of Welch Bound: Gaussian Pulse Improves BER Performance. In: Gong, G., Helleseth, T., Song, HY., Yang, K. (eds) Sequences and Their Applications – SETA 2006. SETA 2006. Lecture Notes in Computer Science, vol 4086. Springer, Berlin, Heidelberg. https://doi.org/10.1007/11863854_31
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DOI: https://doi.org/10.1007/11863854_31
Publisher Name: Springer, Berlin, Heidelberg
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