Complex Valued Block Codes for Ofdm-cdma Application
نویسنده
چکیده
This paper introduces the extension of Walsh-Hadamard block codes in order to obtain complex valued block codes. These complex valued block codes lead to an improved spectral efficiency with additional lower error rate. Applied for low rate concatenated coding schemes required for CDMA uplink transmission, the gain in spectral efficiency due to the new codes can be used for strengthening other codes participating. We observe a gain of about 1:7 dB for BER=10 3 for OFDM-CDMA transmission.
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