A 60-GHz optoelectronic mixing scheme of high image and carrier rejection ratios with an integrated optical single-sideband modulator employed

We report on the first implementation and performance investigation of a 60 -GHz-band optoelectronic image rejection mixing scheme based on a broad-ban d integrated optical single-sideband modulator. We have confirmed a few adv antageous features over electrical image rejection mixers, arising from its nature of being free from electrical phase control of millimeter-wave sign als. We obtained at the TF frequency of 800 MHz rejection ratios of > 40 dB for the image signal and of > 20 dB for the local oscillator (LO) signal i n the LO frequency range of 55-65 GHz. The LO bandwidth can be extended fur ther. The IF bandwidth with an image rejection ratio of > 20 dB was also co nfirmed to be as broad as 550 MHz, which is limited not by the configuratio n but by the bandwidth of the 90 degrees hybrid used in this experiment. Fu rthermore, fiber-optic transmission of a 155.52-Mb/s-DPSK 59.8-GHz optical millimeter-wave signal was successfully demonstrated for a 20-km standard s ingle-mode fiber. A bit error rate of < 10(-9) was achieved at the received optical power of -18 dBm with a negligible dispersion penalty.