EME (communications) - Current EME Communications

Current EME Communications

Amateur radio (ham) operators utilize EME for two-way communications. EME presents significant challenges to amateur operators interested in working weak signal communications. Currently, EME provides the longest communications path any two stations on Earth can utilize for bi-directional communications.

Amateur operations use VHF, UHF and microwave frequencies. All amateur frequency bands from 50 MHz to 47 GHz have been used successfully, but most EME communications are on the 2 meter, 70-centimeter, or 23-centimeter bands. Common modulation modes utilized by amateurs are continuous wave with Morse Code, digital (JT65) and when the link budgets allow, voice.

Recent advances in digital signal processing have allowed EME contacts, admittedly with low data rate, to take place with powers in the order of 100 Watts and a single Yagi antenna.

World Moon Bounce Day, June 29, 2009, was created by Echoes of Apollo and celebrated world wide as an event preceding the 40th anniversary of the Apollo 11 Moon landing. A highlight of the celebrations was an interview via the Moon with Apollo 8 astronaut Bill Anders. He was also part of the backup crew for Apollo 11. The University of Tasmania in Australia with their 26m dish was able to bounce a data signal off the surface of the Moon which was received by a large dish in the Netherlands - Dwingeloo Radio Observatory. The data signal was successfully resolved back to data setting a world record for the lowest power data signal returned from the Moon with a transmit power of 3 milliwatts - about 1,000th of the power of a strong flashlight filament globe. World Moon Bounce Day 2010 was set to precede the Apollo 13 mission sometime in early 2010. The second World Moon Bounce Day was April 17, 2010 and coincided with the landing of Apollo 13 on its 40th anniversary.

In October 2009 visual artist Daniela de Paulis and the CAMRAS radio amateurs association based at Dwingeloo radio telescope (NL) developed a new application of Moonbounce, called Visual Moonbounce, which allows moonbouncing images using the MMSSTV software. The technology was applied to a live performance called OPTICKS during which digital images are sent to the Moon and back in real time and projected live.