The advantage of geosynchronous orbit is that satellites appears stationary. Satellite dishes or antennas tracking the satellite don’t need to move. Any orbits other than geosynchronous require antennas to move to track the satellite. Historically, this added a lot to the complexity and cost of the antenna (although the Soviets employed the “Molniya Orbit” for decades which required dishes to nod up and down from the horizon).
As companies contemplate placing thousands of satellites into low earth orbit, and all of the advantages that confers (less latency, smaller satellites, lower cost), a major challenge appears: How do you design an antenna to track satellites, including frequent handoffs from one satellite to another? And if the antenna is moving in a plane or car, how does that factor in?
Fortunately, there is great progress in a new generation of “steerable antennas”, also described as a “phased array antennas”. Researchers have essentially built the “steering” elements, until now managed through motors, onto a chip. Flat panel antennas are being designed which can track satellites, including through the frequent passing from one to another.
The technology is well-demonstrated, and a number of agreements are being signed between antenna technology firms and satellite companies, such as recent agreements between ALCAN and SES or between Phasor and LeoSat.
Technology firms are still wrestling with costs for steerable flat panel antennas, although with millions likely to be purchased for broadband access, companies are optimistic that prices will fall to a few hundred dollars.