Sending a voice signal 239,200 miles to the lunar surface and back, is
not an easy task. But for amateur radio buffs or “hams”, as they call
themselves, the ultimate dream is to reach for the moon.
“Earth-moon-earth (EME) radio communication has been my life-long
ambition. For an amateur radio enthusiast, EME is similar to what Mount
Everest means for a mountaineer,” said Muneem Hossain Rana. Further
likening his hobby to mountaineering, the Dallas-based expatriate said,
“There is no pecuniary interest involved in this amateur radio thing. It
is an expensive hobby that requires real technical expertise and lot of
time.”
Rana said hams could be very useful in assisting emergency efforts and working with public service agencies, during times of disaster, when regular communications channels are disrupted. “This is because radio amateurs use a variety of voice, text, image and data communications. They also have access to frequency allocations, throughout the radio frequency (RF) spectrum, to enable communication across a city, region, country, continent, or even into space,” he added.
Explaining about EME communication, he said the technique relies on propagation of radio waves from an earth-based transmitter, directed via reflection from the surface of the moon, back to an earth-based receiver. “In other words, it is a two-way communication via radio, where the moon surface is used, instead of atmosphere, to bounce back the signal,” he said.
EME requires a higher grade of ham-radio technology than that used for traditional earth-bound communication, across parts of the radio spectrum approved by governments for amateur use, he added.
“At present, EME provides the longest bi-directional communication path between two stations on Earth. Only about 1,000 hams worldwide have stations capable of moon-bouncing,” Rana said. “My proposal is unique, because I plan to transmit signal from my house at Dallas, Texas, which will be received by a team stationed in Bangladesh, after the signal bounces back from the moon”, he said.
According to websites on EME, the use of the moon as a passive communication satellite was proposed by WJ Bray of the British General Post Office in 1940. It was calculated that with the available microwave transmission power and low noise receivers, it would be possible to beam microwave signals up from the Earth and reflect off the moon.
The “moon bounce” technique, however, was developed by the US military 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. Later, the technique was used by non-military commercial users, and the first amateur detection of signals from the moon took place in 1953.
So why this particular EME communication planned by Rana is unique? He explained that the moon must be above the horizon, in order for EME communications to be possible. But Bangladesh and the US are opposite directions in reference to the moon. “We will get only a couple of minutes at early morning or evening to release the signal, when moon can be sighted both from the US and Bangladesh. No one in the amateur radio community has tried this sort of communication, so far”, he said.
Rana said EME communication needs absolute precision, as the moon is a poor sounding board as it is spinning and has a rough surface that can disrupt signals. The hams’ voices must survive atmospheric interference over the long round-trip journey in a discernible form, he said.
In the backyard of his Dallas house, Rana has already started arrangements to establish the set-up for his communication. At first, he will try it with a 32-element beam antenna, and then it will be an array of four beam antennas. He will start transmit an array of signals from the MHz frequency band to the G Hz band.
Rana, who recently visited Bangladesh, said he already had meetings with the Bangladeshi team. “There are about 100 registered hams in Bangladesh. I have teamed up with some of them. We are now doing groundwork to select a suitable location in Bangladesh, where the signal can be received without interruption, after it bounces back from the moon”, he said.
Considering all the complexities involved, Rana said that their experiment needed a lot of patience. “We may pass six months or even a year without success, but that is the way our hobby is. Theoretically it is possible, so we will keep on trying,” he said.
Rana said that he has been an amateur radio enthusiast from his early years. “I was one of the first hams in Bangladesh. We started the movement in Bangladesh from the early 70s. It was due to our constant persuasion that the government gave official permission to have communication, through the amateur radio in 1992,” he added.
Rana said hams could be very useful in assisting emergency efforts and working with public service agencies, during times of disaster, when regular communications channels are disrupted. “This is because radio amateurs use a variety of voice, text, image and data communications. They also have access to frequency allocations, throughout the radio frequency (RF) spectrum, to enable communication across a city, region, country, continent, or even into space,” he added.
Explaining about EME communication, he said the technique relies on propagation of radio waves from an earth-based transmitter, directed via reflection from the surface of the moon, back to an earth-based receiver. “In other words, it is a two-way communication via radio, where the moon surface is used, instead of atmosphere, to bounce back the signal,” he said.
EME requires a higher grade of ham-radio technology than that used for traditional earth-bound communication, across parts of the radio spectrum approved by governments for amateur use, he added.
“At present, EME provides the longest bi-directional communication path between two stations on Earth. Only about 1,000 hams worldwide have stations capable of moon-bouncing,” Rana said. “My proposal is unique, because I plan to transmit signal from my house at Dallas, Texas, which will be received by a team stationed in Bangladesh, after the signal bounces back from the moon”, he said.
According to websites on EME, the use of the moon as a passive communication satellite was proposed by WJ Bray of the British General Post Office in 1940. It was calculated that with the available microwave transmission power and low noise receivers, it would be possible to beam microwave signals up from the Earth and reflect off the moon.
The “moon bounce” technique, however, was developed by the US military 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. Later, the technique was used by non-military commercial users, and the first amateur detection of signals from the moon took place in 1953.
So why this particular EME communication planned by Rana is unique? He explained that the moon must be above the horizon, in order for EME communications to be possible. But Bangladesh and the US are opposite directions in reference to the moon. “We will get only a couple of minutes at early morning or evening to release the signal, when moon can be sighted both from the US and Bangladesh. No one in the amateur radio community has tried this sort of communication, so far”, he said.
Rana said EME communication needs absolute precision, as the moon is a poor sounding board as it is spinning and has a rough surface that can disrupt signals. The hams’ voices must survive atmospheric interference over the long round-trip journey in a discernible form, he said.
In the backyard of his Dallas house, Rana has already started arrangements to establish the set-up for his communication. At first, he will try it with a 32-element beam antenna, and then it will be an array of four beam antennas. He will start transmit an array of signals from the MHz frequency band to the G Hz band.
Rana, who recently visited Bangladesh, said he already had meetings with the Bangladeshi team. “There are about 100 registered hams in Bangladesh. I have teamed up with some of them. We are now doing groundwork to select a suitable location in Bangladesh, where the signal can be received without interruption, after it bounces back from the moon”, he said.
Considering all the complexities involved, Rana said that their experiment needed a lot of patience. “We may pass six months or even a year without success, but that is the way our hobby is. Theoretically it is possible, so we will keep on trying,” he said.
Rana said that he has been an amateur radio enthusiast from his early years. “I was one of the first hams in Bangladesh. We started the movement in Bangladesh from the early 70s. It was due to our constant persuasion that the government gave official permission to have communication, through the amateur radio in 1992,” he added.
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