Implementation of OFDM by using VHDL

In this work, the VHDL codes for the main blocks of Orthogonal Frequency Division Multiplexing (OFDM) technique are formed in order to implement on a Field Programmable Gate Array (FPGA). The VHDL codes of each block on the transceiver of OFDM technique such as modulation, Inverse Discrete Fourier Transform (IDFT), Discrete Fourier Transform (DFT) and demodulation are composed separately. The machine codes (bit stream files) of the modulation and demodulation blocks obtained after synthesizing by using "Quartus II 13.1" are loaded into the FPGA with the number of 4CE11529C7 located on DE2- 115 Kit of Altera Corporation. 16-ary Quadrature Amplitude Modulation (16-QAM) is chosen as a baseband digital modulation technique. IDFT/DFT blocks are implemented by using "MegaWizard Plug-In" tool of Altera Corporation using Fast Fourier Transform algorithm for DFT. A random array with the 640 word length for the input data of OFDM technique is created by using MATLAB. The functional tests of VHDL codes for each block are conducted over "Altera Modelsim 10.1". On each stage, the outputs of functional tests are compared with the results of MATLAB models. It is observed that the input data for the transmitter of OFDM technique is the same with the output data of receiver.