Millimeter-wave broad-band fiber-wireless system incorporating baseband data transmission over fiber and remote LO delivery

We present the first demonstration of a millimeter-wave (mm-wave) broadband fiber-wireless system which incorporates baseband data transmission in bot h the downstream (622 Mb/s) and upstream (155 Mb/s) directions. The local o scillator (LO) required at the remote antenna base station for up- and down conversion to/from the mm-wave radio frequency (RF) is delivered remotely v ia a modulation scheme that is tolerant to the effects of fiber chromatic d ispersion on the detected LO carrier power. The technique employs a single dual-electrode modulator located at the central office (CO) and the data an d an RF signal at a frequency equal to half the LO frequency, are applied s imultaneously to the device, The modulation scheme was optimized as a funct ion of the modulator operating conditions. Simultaneous bidirectional radio transmission in the mm-wave fiber-wireless network was implemented using s pecially designed mm-wave diplexers located at the base station (BS) and cu stomer unit, and a single Ka-band printed antenna array at the BS operating simultaneously in transmit and receive mode. Error-free data transmission was demonstrated for both down- (34.8 GHz) and uplinks (37.5 GHz) after 20 km of single-mode optical fiber and a bit error rate (BER) of 10(-6) was ac hieved after the inclusion of a 2-m radio link.