Development of a Deployable Optical Receive Aperture

The Deployable Optical Receive Aperture (DORA), a new technology being developed jointly between Jet Propulsion Laboratory (JPL) and Arizona State University (ASU), is based on deploying arrays of fast optical detectors to create large receive apertures and seeks to achieve gigabit connectivity at distances of thousands of kilometers. Small spacecraft forming the LunaNet communications network and equipped with optical communications systems, such as the proposed DORA aperture, should be able to communicate at Gigabit per second rates over long distances. This data rate enhancement can allow gigabit per second connectivity between lunar assets (astronauts, rovers, instruments) and the lunar gateway. Under sponsorship of NASA's Small Spacecraft Technology Program (SSTP), JPL is deploying the DORA payload and ASU is developing a 3U CubeSat for a follow-on low-Earth-orbit (LEO) mission to demonstrate DORA's capabilities. The basic DORA payload consists of 5 receiver panels, a transmitting telescope and processing units. Each receiver panel contains dozens of power-combined detectors to mimic a large optical aperture. The total receive aperture of DORA is provided by the sum of the effective detecting area of the 5 panels. The transmit telescope includes a 200mW, 850nm laser and a voice-coil fast steering mirror (FSM). The resulting DORA terminal should be able to provide duplex connectivity at rates up to 1 gigabit per second at the distances of interest. We have designed the entire DORA payload and plan to present the test results of our DORA engineering model. These results include angle-of-arrival, data rate and bit error rate measurements.