Q-link: A portable 30 GHz solid-state 120 Mb/s digital radio

A short hop (2 to 5 km) digital data link which operates with a 30 GHz carrier frequency at 120 mb/s is described. The prototype transmitter consists of a 30 GHz impatt oscillator giving 100 mW is CW power followed by a p-i-n switch which is used to on/off modulate the carrier. Small parabolic reflectors are used to send and receive the information between the terminals, and the digital information is recovered by a superheterodyne receiver at the remote end. The link is a 2-way system in which the two channels are isolated by transmission in orthogonal polarization and separation in frequency. The terminals of the link are solid state modules having a volume of about 0.027 cu m and weighing only 12 kg, which makes them highly portable. Each module can process a digital data stream at rates exceeding 100 Mbits/sec. Possible applications are briefly discussed.