Provided by: International Journal of Engineering Trends and Technology
In this paper, the authors proposed a STTC-OFDM system which is based on IEEE 802.16e OFDMA specification and supports the distributed subcarrier allocation of Partial Usage of Sub Channels (PUSC) for DownLink (DL) transmission. The Fast Fourier Transforms (FFT) size 1048. The length of Cyclic Prefix (CP) is 128 sampling periods. The modulation schemes of Quadrature Phase Shift Keying (QPSK) and 16Quadrature Amplitude Modulation (16QAM) are supported for data subcarriers, while Binary Phase Shift Keying (BPSK) is adopted for pilot subcarriers and preamble symbols. A DL sub-frame is composed of one preamble symbol and 40 OFDM data symbols.