To address the fea sibility of orthogonal frequency division multiplex (OFDM) radar signal, a real time OFDM radar signal generator based on field programmable gate array (FPGA) a nd fast Fourier transform (FFT) algorithm is proposed on research of synthesis a nd waveform design. Orthogonal multi carrier modulation is implemented with dig i tal signal processing approach. Signal parameters and the modulation scheme are reconfigurable, and can be adapted to different applications and platforms. The design principle and key steps involved in OFDM signal generation are discussed, and test results are provided. Test shows the feasibility of the OFDM signal generator, which is fundamental for theoretical research and applica tion of OFDM radar systems.