Abstract: A wireless atmospheric site-to-site full-duplex (i.e., simultaneous transmit and receive) laser communication system, typically for wideband (high-speed) data, voice, and/or video transmission. The system includes at least one laser communication transceiver each having an electro-optical transmitter that includes a laser source for generating laser light to be transmitted site-to-site and at high speed, an electro-optical receiver that includes a baffle assembly for receiving light directly onto a detector, without an intermediate field stop and re-imaging relay optics to reject off-axis light sources. Wideband data are transmitted and received through the atmosphere by the electro-optical transmitter and the electro-optical receiver. The data to be transmitted through each laser communication transceiver is inputted through a fiber-optic receiver and outputted by a fiber-optic transmitter.

Abstract: A laser communication system for full duplex wideband data transmission includes first and second terminals having dichroic wavelength-multiplexed optical systems wherein transmitted and received light are multiplexed along a path through the same aperture. The optical systems each preferably comprise a cassegrain receiver having primary and secondary mirrors for directing both transmitted and received laser light. Modulated laser light is generated by a high-power laser diode which is actively cooled by a thermoelectric cooler. A window in the housing, through which the modulated laser light travels, includes a transparent resistive coating to which electrical current is applied to control the temperature of the window. The aspheric primary mirror has a highly reflective surface, preferably a single-point diamond-turned mirror surface, formed on an aluminum substrate as a single piece.