System model with adaptive modulation and frequency hopping in wireless networks

This article describes the features of the proposed system based on the 802.16 standard and orthogonal frequency division multiple access (OFDMA) with synergy of additional advanced technologies. The system enables dynamic subcarrier allocation to users. Subcarriers are allocated according to the quality of the received signal. Signal-to-noise ratio (SNR) per subcarriers is separately calculated for each user from the preambles placed in the beginning of the data frame. The proposed method performs adaptive modulation and coding (AMC) with frequency hopping (FH). The results are compared to the existing subcarrier permutations. They show greater system throughput at lower bit error rate (BER).