HAMNET REPORT 28TH NOVEMBER 2021
Engineering and Technology says that a European team of scientists have, for the first time ever, bounced a LoRa (LOng RAnge) message off the Moon. The feat set a new record of 730,360km for the furthest distance a LoRa message has ever travelled. It was also the first time a data message was bounced using an off-the-shelf small RF (radio-frequency) chip. For a brief moment in time, the entire message ‘PI9CAM’ was in space on its way from Earth to the Moon and back.
The experiment also proved that LoRa technology, used for many IoT (Internet of Things) applications, can cover such great distances and that it is possible to send and receive low-powered messages from the Moon. This could become relevant for future lunar communications.
The team, some of whom were licensed radio amateurs, consisted of Jan van Muijlwijk (CAMRAS); Tammo Jan Dijkema (CAMRAS); Thomas Telkamp (Lacuna Space), and Frank Zeppenfeldt (ESA). To achieve the transmission, the team used the Dwingeloo radio telescope, operated by the CAMRAS foundation in the Netherlands. The radio telescope has a history of being used in amateur radio experiments and is now often used for Moon bounces.
Nicolas Sornin, co-inventor of LoRa, said: “This is a fantastic experiment. I had never dreamed that one day a LoRa message would travel all the way to the Moon and back. I am impressed by the quality of the data captured. This dataset is going to become a classic for radio communications and signal processing students. [I send a] big thumbs up to the team and CAMRAS foundation for making this possible.”
Telkamp, CTO of Lacuna Space, a global connectivity provider for the IoT, said: “Seeing the message coming back from the Moon was exhilarating. From the round-trip time we were able to calculate the distance to the Moon, matching very well the predicted values of Nasa’s JPL Horizons ephemeris system. We even used the echo to see the shape of the Moon, which we didn’t imagine we could.”
LoRa is one of the low-power wide-area network communication technologies and is Semtech’s proprietary ultra-long-distance wireless transmission technology. On 5 October 2021, the team transmitted the signal with a Semtech LR1110 RF transceiver chip (in the 430-440Mhz amateur band), amplified to 350 Watt, using the 25-metre dish of the telescope. 2.44 seconds later, it was received by the same chip.
Using the LR1110 RF chip, the team also measured the frequency offset due to the Doppler effect caused by the relative motion of the Earth and the Moon.
One of the messages sent and received contained a full LoRaWAN frame, consisting of a header (information such as device address and message counter), payload (the data actually sent), and payload CRC (integrity check of payload).
In addition to the LoRa chips, the team used an SDR (software-defined radio) to capture both the transmitted and received signal for further analysis. These measurements together with analysis notebooks will be published as open data.
Michael Taylor ZS1MJT, our Regional Director of HAMNET in the Western Cape has advertised a Drone Briefing, by Fabian Higgins, about the Provincial Emergency Medical Services’ Drone Programme. It will take place on Wednesday the 8th December at 18h30, and should last about 45 minutes. He will describe the capabilities of the rescue drone, and how WSAR rescue teams can collaborate with the drone team for best results. The talk will be followed by Q and A time.
Michael has sent an invitation to Western Cape HAMNET members with a URL to fill in a registration form. Apply to Michael at email@example.com if you don’t receive the notification.
At the IUCN World Conservation Congress in Marseille, France, in September, the Mediterranean plastic crisis was firmly on the agenda. Representatives from tourist-sensitive countries, including France, Italy, Greece and Cyprus, lined up to bemoan the level of plastic pollution and to highlight their own efforts to combat the problem.
According to a report last year by the International Union for Conservation of Nature, the total volume of plastic waste in the Mediterranean, found mostly beneath the waves, could be as much as 3.5 million tons, with anything between 150,000 and 610,000 additional tons finding its way into the sea every year.
For the 21 countries that share the 28,000 km Mediterranean coastline, the half a billion people who live on the sea or along the 1,693 watersheds that feed it, and the 340 million tourists who typically visit in a normal year, this is a growing problem.
But of all those countries, just one has been singled out as the biggest single source of the problem. The finger of blame is pointing squarely at Egypt, which the IUCN says is responsible for releasing more plastic into the sea than any other nation, and twice as much as the second-worst offender.
According to the IUCN report “The Mediterranean: Mare Plasticum” — Latin for “the plastic sea” — is “widely regarded as one of the most threatened environments in the world” and “is subject to a now ubiquitous, man-made disaster: Plastic pollution.”
The worst offender, says the IUCN, is Egypt, responsible each year for the “leakage” of over 74,000 tons of macroplastics — pieces with a diameter greater than 5 mm — followed by Italy (34,000 tons) and Turkey (24,000 tons).
Together, these three “hotspot” countries contribute more than 50 percent of the 216,269 tons of macroplastics that end up in the Mediterranean Sea each year, overwhelmingly as a result of “mismanaged waste.”
When it comes to microplastics — over 13,000 tons of which finds its way into the sea — Egypt fares little better, ranking second only to Italy (3,000 tons a year), with 1,200 tons. Tyre dust accounts for more than half of the total of microplastics, followed by textiles (33 percent) and the plastic microbeads used in cosmetics (12 percent).
Although bottles and other plastic waste are omnipresent on Mediterranean beaches, most of the polluting plastic is beneath the surface, fouling sediment and disrupting the life cycles of multiple species of fish and aquatic plants.
Time for us all to start picking up after us, folks!
This is Dave Reece ZS1DFR reporting for HAMNET in South Africa.