ThinKom Solutions has revealed a new solution for land-based gateways, designed to accommodate the rising numbers of low Earth orbit (LEO_ and medium Earth orbit (MEO) satellite constellations. Described as an “array of arrays”, the ThinKom solution could provide a better performing alternative to the commonly seen dish farms.
Bill Milroy, Chairman and Chief Technology Officer of ThinKom Solutions commented in a press release,
“The proliferation of cubesats, nanosats, microsats and other miniaturized satellites will require a new way of thinking when it comes to gateway antenna technology. The answer is not to deploy more and larger dish farms. Instead, we’re proposing an entirely new paradigm that’s designed for the future yet employs currently available proven phased array technology.”
The system is based on ThinKom’s already proven phased array antenna technology, which is already in use by 15 different airlines on more than 1,300 aircraft worldwide. The technology has been proven in real life situations, having clocked up more than 10m hours of reliable operation.
The problems with parabolic dish farms
The current generation gateways rely on large parabolic dishes to connect to geostationary (GEO) satellites. The nature of these dishes means they can only link to one pathway per dish. Due to their cumbersome and complex drive mechanisms, these dishes are unable to rapidly repoint to another source, limiting their usefulness with faster moving LEO satellites.
These systems themselves are big and heavy, and because one dish can block the signal to another, they need to be sited with sufficient separation between them. As such, a ‘dish farm’ will occupy a large area of real estate, something which only adds to the cost of installation and maintenance.
Such multi-dish gateways are not only expensive to purchase and maintain, but can take months to set up too. The nature of the large dishes means they are susceptible to inclement weather such as snow and ice, and even a moderate wind could put their integrity at risk. This leads them to require robust concrete bases or purpose-built protective structures to prevent damage from wind and weather.
ThinKom’s solution promises to be smaller, more lightweight and easier to deploy. They’ll take up less space, require less maintenance and will be cheaper to install too. Most importantly, they’re already being used and have been proven to be a successful technology.
ThinKom’s phased-array antennas
The approach taken by the Californian company is to pack multiple phased array antennas into a single combined unit. With all the units working intelligently together, the antenna is capable of tracking multiple LEO, MEO and GEO satellites simultaneously. It can support multiple links, and uses software to modify the number of beams and radiation properties to meet the throughput demands in terms of the number of satellites in view.
The nature of this new gateway solutions means it uses far less energy than an electronically scanned array. Overall, it presents look angles of between five and 90 degrees elevation and a full 360 degree outlook in azimuth.
The fixed convex shape of the array gives it maximum low elevation coverage and naturally sheds rain and snow to reduce required maintenance. Although the system is reconfigurable for specific situations, ThinKom says that a standard array of less than two meters tall with a footprint of less than seven square meters is equivalent to eight 2.4m parabolic dishes or four larger 4.5m dishes.
This small size profile opens more opportunities to install gateways in previously unsuitable locations, such as rooftops of buildings. Individual units can be swapped out without service interruption, thanks to the in-built redundancy, which the manufacturer hopes could completely eliminate downtime.
“Most importantly, we’re not out to reinvent the wheel. This solution uses our patented, proven phased-array antenna technology that is in service today, minimizing R&D and time-to-market.”
ThinKom’s ThinAir Ka2517 Ka-band phased arrays have successfully completed a battery of ground and air tests and are now commercially available. Earlier this year, testing demonstrated data speeds of 185 Mbps downlink and 35 Mbps uplink with zero dropped data packets over a geostationary Ka-band satellite.
In July, testing with the Telesat LEO satellite saw the antenna successfully acquire, track and maintain end to end connectivity, with data rates of up to 370 Mbps downlink and 110 Mbps uplink achieved. The system also successfully switched between the LEO satellite and a GEO satellite and back again, with switching times of under a second.