The Naval Center for Space Technology at the Naval Research Laboratory reports the latest results from the long-range, maritime, free-space lasercom test facility located between Chesapeake Beach, MD and Tilghman Island, MD. The two sections of the facility are separated by 16.2 km of the Chesapeake Bay. Using a new OC-48 receiver developed by NRL's Optical Science Division with a sensitivity of -33dBm for 10 -9 bit error rate at 2.5 Gbps, we have closed a 32.4 km maritime lasercom link (round

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... rip across the Chesapeake Bay) and performed bit error rate testing while transmitting 1.13 Terabytes of data. Bit error rate testing was also performed at lower data rates when atmospheric conditions were not favorable for high speed (2.5 Gbps), including testing at 150 Mbps through light fog and rain. In addition, we have set up a system for digitizing and transmitting full-color, uncompressed, video along with six audio channels and three RS-232 data channels over the maritime link. The digital link operated at 311 Mbps and could be maintained indefinitely, depending on atmospheric conditions. Several complete videos were transmitted in entirety or in part as well as live video from a handheld camcorder to test the system operation and robustness. The transmitter and receiver were co-located on the western shore of the bay at the NRL Chesapeake Bay Detachment. The data for both the bit error rate testing and the video was transmitted across the bay and returned from an array of retroreflectors located on a tower at Tilghman Island on the eastern shore. The lasercom links were closed with static pointing and with no active atmospheric aberration mitigation such as adaptive optics or fast steering mirrors on the receiver optics. Keywords: Free-space lasercom, maritime, bit error rate, free-space optical communication the Remote Sensing Division at the Naval Research Laboratory (NRL) has been operating a free-space optical communications (FSO) testbed across the Chesapeake Bay. The west section of the testbed is located at the Chesapeake Bay Detachment (CBD), and the east end is located across the bay at Tilghman Island (TI). Both locations are in Maryland, and they are separated by 16.2 km of water. This facility is utilized for field-testing of optical components such as modulators 1 , erbium doped fiber amplifiers 2,3 (EDFA), and detectors developed and built at NRL along with commercially available components 4 . In addition to conventional lasercom, the facility at CBD is used to test communication links established with a modulating retroreflector 5,6,7 . These links include ground to UAV and shore to ship links transferring real-time video and other data. Outside organizations desiring a long maritime FSO link to test their own equipment have used the Chesapeake Bay Lasercom Facility. The free-space lasercom test facility (LCTF) Public reporting burden for the collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden, to Washington Headquarters Services, Directorate for Information Operations and Reports, 1215 Jefferson Davis Highway, Suite 1204, Arlington VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to a penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number.