Channel Coding Aspects in an OFDM-CDMA System
نویسندگان
چکیده
| This paper investigates coding aspects in an OFDM-CDMA environment. The inherent bandwidth expansion in CDMA systems offers many possibilities for the application of powerful codes with low code rates. Three different coding strategies are under consideration: the combination of convolutional and repetition codes (conventional DS-CDMA system), a code-spread system consisting of one very low rate convolutional code, and a serial concatenation of convolutional, Walsh and repetition code. Analytical and simulation results turn out that the Walsh coded system is the best choice among the considered scenarios.
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تاریخ انتشار 2000