Demands from 5G means cheaper low earth orbit (LEO) satellites are needed to perform multiple satcomms functions.

The need for ubiquitous coverage for many of the proposed 5G use cases – in particular the Connected Car – has necessitated a plan to include other connectivity solutions such as WiFi and satellite communications in future hybrid networks, in order to ensure that there will be no holes in the 5G coverage map. The low earth orbit (LEO) satellites that are being developed for the space segment are of necessity very different from the high-cost, high-reliability geostationary (GEO) satellites that have traditionally been used for satcomms, or even the medium earth orbit (MEO) craft that make up the GPS, Glonass and Galileo constellations used for satellite navigation. One of the key challenges for the new satellites is the need to use commercial-off-the-shelf (COTS) components rather than radiation-hardened, space-qualified components, whose cost would be prohibitive. Rigorous functional qualification of the full system will of course still need to be carried out, to ensure adequate reliability for space deployment.

Although satellites can deliver virtually blanket coverage, and potentially also the high data rates demanded for 5G, they do have a disadvantage in terms of latency. Due to the long distances involved, latency for an LEO is typically 30ms – better than the 40ms that is typically achieved by 4G LTE, but poor compared with the 5G target of less than 1ms.

LEO satellite main players

There are a number of players in this new LEO satellite field – the main ones include: OneWeb Satellites (a joint venture between OneWeb and Airbus); SpaceX; Inmarsat; Eutelsat, Intelsat and eightyLEO. Facebook is also involved, via a joint venture with Eutelsat, although they suffered a considerable setback when their first satellite was destroyed during takeoff.

The former satellite mobile comms operators Iridium and Globalstar – rescued from bankruptcy after the failure of their initial business plans – are both also reported to be working on supporting 5G networks with LEO satellites. Most, if not all, of the LEO satellites are expected to have payloads operating in Ka-band (26 – 40GHz).

Last month, Elon Musk’s SpaceX launched the first two prototype global internet satellites (known as known as Microsat 2a and 2b) of its Starlink network into orbit, as secondary payloads on the company’s next Falcon 9 launch.

OneWeb is expected to launch the first of its test satellites later in 2018, with plans to begin preliminary operations in 2019.

eightyLEO is a German start-up, launched at the beginning of 2015 by CEO Matthias Spott with a vision of a satellite network specifically serving the IoT. It plans to launch the first three demonstration satellites of its ‘Kaskilo’ constellation in late 2018 or early 2019.

Microwave supply chain

Teledyne Defence, based in Shipley, UK, announced in June 2016 that it had been awarded a major supply contract by OneWeb Satellites, to supply communications repeater equipment to support OneWeb’s planned deployment of 900 small satellites for global broadband Internet access. As part of this contract, Teledyne has designed and is now supplying a complete customised MMIC chipset for this first generation of satellites, which are in pilot production in OneWeb’s facility in Toulouse. Mass production of the satellites will be split between Toulouse and a larger operation in Florida. The Teledyne MMICs have been processed in different European foundries and also at WIN Semiconductor. Discussions have now commenced about a follow-on constellation (Generation 2), consisting of around 2000 satellites, which are likely to operate at a higher carrier frequency to provide increased bandwidth.

Another company in the British Isles that is active in microwave devices for 5G satellite applications is Arralis, based in Limerick, Ireland, which announced at last year’s Paris Air Show a €650,000 first-phase contract with the European Space Agency (ESA) for its Leonis Ka-band chipset, said to be an enabler for massive data rate communications both for commercial applications including 5G and for science missions. The chipset includes all the MMICs and circuits required to build both the satellite and ground front ends, to connect with high power amplifiers and antennas. The Leonis chipset comprises devices that are all fabricated on a low noise, space-qualified GaAs process, and was specifically developed to meet the requirement for low-cost K/Ka-band satellite equipment that can readily interface with existing digital Internet hardware. The transmit (17 – 21GHz) and receive (27 – 31GHz) band coverage allows for both ground-to-space and space-to-ground applications. In addition to 5G communications via LEO satellites, the chipset is also said to be suitable for use in airborne high speed WiFi, drone constellations and SAT-Drone-Ground data networks, satellite-to-automotive connectivity, connected vehicles, last mile solutions, and IoT and M2M communications.

EuMW Forum

Space applications also featured prominently on the conference programme at European Microwave Week in Nuremberg, with a session entitled, “The 2017 Defence, Security and Space Forum” addressing the application of RF and microwave technology to “The Internet of Space”. Recognising that vast areas of the globe, ranging from oceans and deserts through to inhabited areas that suffer poor infrastructure development, have little or no Internet connectivity, the session discussed the new class of satellite communication services that is addressing this challenge using platforms ranging from LEO to GEO satellites. Speakers included representatives from Airbus, Deloitte, eightyLEO, Keysight Technologies, Qorvo, MACOM and Rohde & Schwarz, with a lunchtime presentation from Asif Anwar of Strategy Analytics.

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