A Fuzzy Logic Approach to Adaptive Coding & Modulation in OFDM
نویسنده
چکیده
Adaptive coded modulation is one of the key technologies used to enhance the capabilities of future communication network. Many adaptive modulation techniques have been investigated for the enhancement of transmission rate in combination with OFDM under AWGN channel .OFDM will provide much higher bandwidth efficiency. This is due to the fact that in OFDM the spectra of individual subcarriers are allowed to Overlap. The OFDM system always suffers with the problem of increase in bit error rate and decrease in spectral efficiency. Various modulation techniques are available for OFDM communication like 4QAM, 8QAM and higher modulation techniques. Lower modulation techniques like 4QAM and 8QAM reduce the bit error rate but decrease the spectral efficiency. So a technique is required which provides better tradeoff between them. So, adaptive coded modulation is the answer to this problem. The proposed work in this paper is to design a Fuzzy rule based system (FRBS) for coded modulation.
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