60 GHz broadband free-space communication using dual-wavelength photonic signal generation

A 60 GHz free-space communication system is demonstrated with broadband data encoding and a novel photonic millimeter-wave carrier generator. A 60.8 GHz carrier signal is generated by photomixing two optical subcarriers sourced from a dual-wavelength laser based on stimulated Brillouin scattering in optical fiber. Data is baseband encoded onto a single optical subcarrier using an optical phase modulator and photonically upconverted to the 60.8 GHz RF carrier. Data rates of 1.65 Gbps are demonstrated, with the goal of facilitating wireless personal area networking based on a fiber-distributed network architecture. The implemented encoding scheme is intrinsically dispersion tolerant, enabling remoting of signals over long distances between a base station and wireless access nodes. The prototype link was tested in an indoor setting at ranges up to 30 m using a low-gain transmitter antenna and high-gain receiver antenna. Good bit-error ratios are demonstrated as a function of range. A building-to-building communication link, with long-distance fiber distribution to the wireless transmitter, is demonstrated at a range of 78 m.