| Summary: | In this paper, we propose and experimentally demonstrate a millimeter-wave (mm-wave) system at 75 GHz with discrete Fourier transform spread (DFT-S) orthogonal frequency-division multiplexing (OFDM) signal transmission. The baseband signal is modulated by a directly modulated laser at the transmitter, and the mm-wave signal is converted to a lower frequency one by an envelope detector at the receiver. The intrasymbol frequency-domain averaging (ISFA) is used for channel estimation and a Volterra nonlinear equalizer is adopted to mitigate the nonlinearity caused by signal-signal beat interference. In this system, a 2-Gbd 16-ary quadrature amplitude modulation (QAM) DFT-S OFDM signal is delivered over 4-m wireless link under the bit error ratio of 3.8 × 10<sup>-3</sup>. Our experimental results show that the ISFA and the Volterra nonlinear equalizer can improve the system performance by about 2-dB and 1-dB receiving sensitivity, respectively. This is the first time the Volterra nonlinear equalizer has been used in a W-band mm-wave system to improve wireless transmission performance.
|
|---|
