Earth-Moon-Earth, also known as moon bounce, is a radio communications technique which relies on the propagation of radio waves from an earth-based transmitter directed via reflection from the surface of the moon back to an earth-based receiver. EARTH was a short-lived Japanese vocal trio which released 6 singles and 1 album between 2000 and 2001
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History
The use of the moon as a passive communications satellite was proposed by Mr W. Bray of the British General Post Office in 1940. The General Post Office (GPO was officially established in England in 1660 by Charles II and it eventually grew to combine the functions of both the state It was calculated that with the available microwave transmission powers and low noise receivers, it would be possible to beam microwave signals up from earth and reflect off the moon. It was thought that at least one voice channel would be possible. [1]
The "moon bounce" technique was developed by the United States Military in the years after World War II, with the first successful reception of echoes off the moon being carried out at Fort Monmouth, New Jersey on January 10, 1946 by John H. DeWitt as part of Project Diana. Communication Moon Relay project (also known as simply Moon Relay, or alternately Operation Moon Bounce) was a Telecommunication project carried out by The United States Armed Forces are the overall unified military forces of the United States World War II, or the Second World War, (often abbreviated WWII) was a global military conflict which involved a majority of the world's nations, including Fort Monmouth is an installation of the Department of the Army in Monmouth County New Jersey Events 49 BC - Julius Caesar crosses the Rubicon, signaling the start of civil war. Year 1946 ( MCMXLVI) was a Common year starting on Tuesday (link will display full 1946 calendar of the Gregorian calendar. John H DeWitt Jr ( February 20, 1906 – January 25, 1999) was an American pioneer in radio broadcasting Radar astronomy and Project Diana, named for the Roman Moon goddess Diana, was a project of the US Army Signal Corps to bounce radio signals off the Moon This was followed by more practical uses, including a teletype link between the naval base at Pearl Harbor, Hawaii and United States Navy headquarters in Washington, DC. A teleprinter ( Pearl Harbor is a Harbor on the Island of O{{okina}}ahu, Hawaii, west of Honolulu. Washington DC ( formally the District of Columbia and commonly referred to as Washington, the District, or simply D In the days before communications satellites, a link free of the vagaries of ionospheric propagation was revolutionary. A communications satellite (sometimes abbreviated to comsat) is an artificial Satellite stationed in space for the purposes of Telecommunications. Radio propagation is a term used to explain how Radio waves behave when they are Transmitted, or are propagated from one point on the Earth
Later, the technique was used by non-military commercial users, and the first amateur detection of signals from the moon took place in 1953. Year 1953 ( MCMLIII) was a Common year starting on Thursday (link will display full calendar of the Gregorian calendar.
Current EME communications
As the albedo of the moon is very low (around 12%), and the path loss over the 770,000 kilometre return distance is extreme (around 250 dB depending on VHF-UHF band used), high power (more than 100 watts) and high-gain antennas (more than 35 dB) must be used. The albedo of an object is the extent to which it diffusely reflects light from the sun Path loss (or path attenuation) is the reduction in power density ( attenuation) of an Electromagnetic wave as it propagates through space The high-gain antenna (HGA is an antenna with a focused narrow radiowave beam width In practice, this limits the use of this technique to the spectrum at VHF and above. Very high frequency (VHF is the Radio frequency range from 30 MHz to 300 MHz.
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. Digital signal processing ( DSP) is concerned with the representation of the signals by a sequence of numbers or symbols and the processing of these signals This page lists examples of the power in Watts produced by various different sources of energy A Yagi-Uda Antenna, commonly known simply as a Yagi antenna or Yagi, is a Directional antenna system consisting of an array of a dipole
Modulation types and frequencies optimal for EME
Gallery
 An array of 8 Yagi antennas for 144 MHz EME at EA6VQ, Balearic Islands, Spain |
 A part of 144 MHz EME antenna array at WA6PY in California, USA |
 A dish antenna for microwave EME work at WA6PY, California, USA |
References
- ^ Pether, John (1998). Very high frequency (VHF is the Radio frequency range from 30 MHz to 300 MHz. A continuous wave or continuous waveform ( CW) is an Electromagnetic wave of constant Amplitude and Frequency; and in Mathematical WSJT is a computer program used for weak- signal Radio communication between Amateur radio operators. WSJT is a computer program used for weak- signal Radio communication between Amateur radio operators. A continuous wave or continuous waveform ( CW) is an Electromagnetic wave of constant Amplitude and Frequency; and in Mathematical WSJT is a computer program used for weak- signal Radio communication between Amateur radio operators. Single-sideband modulation ( SSB) is a refinement of Amplitude modulation that more efficiently uses electrical power and bandwidth. Microwaves are electromagnetic waves with Wavelengths ranging from 1 mm to 1 m or frequencies between 0 A continuous wave or continuous waveform ( CW) is an Electromagnetic wave of constant Amplitude and Frequency; and in Mathematical Single-sideband modulation ( SSB) is a refinement of Amplitude modulation that more efficiently uses electrical power and bandwidth. The Post Office at War. Bletchley Park Trust, 25. Bletchley Park, also known as Station X, is an estate located in the town of Bletchley, in Buckinghamshire, and (since 1967 part of Milton Keynes
See also
Information theory is a branch of Applied mathematics and Electrical engineering involving the quantification of Information. Meteor burst communications, or MBC for short is a radio Propagation mode that exploits the ionized trails of Meteors during Atmospheric A passive radio link deflection, or passive repeater is a plant for the implementation of a Microwave link, in which because of an obstacle inDapyx Software network: MP3 Explorer | Ebook Manager | Zenithic