ThinKom ThinAir Ku-band antenna. Photo: ThinKom

Antennas that function with satellites in both Geostationary Orbit (GEO) Non-Geostationary Orbit (NGSO) as a hybrid solution are essential for using the growing supply of satellite capacity in space, ThinKom CTO Billy Milroy said in a Via Satellite webinar on Tuesday. 

Milroy said ThinKom has verified that both its Ka-band ThinAir 2517 and Ku-band ThinAir 3030 airborne satellite antennas are interoperable between different orbits. The Ka-and 2517 VICTS (Variable Inclination Continuous Transverse Stub) antenna was tested on a Gulfstream III aircraft with SES satellites in both GEO and SES’s O3b satellites in Medium-Earth Orbit (MEO). He said the antenna seamlessly roamed back and forth between GEO and MEO satellites, handed off MEO to MEO, and worked with applications running in the background. The antenna tracked LEO and MEO satellites and demonstrated 370+ Mbps forward link on Telesat LEO1. 

The Ku- band 3030 VICTS array system was tested with OneWeb satellites in LEO for both inter-satellite and intra-satellite beams. It demonstrated a forward link of greater than 350 Mbps and return link greater than 125 Mbps, with latencies less than 50 ms. 

ThinKom has demonstrated make-before-break and even full duplex two satellites simultaneously with both terminals. Milroy also said the antennas can do dual, simultaneous, make-before-break handoffs, but it adds cost and makes the system 20% larger. 

He said the high agility of ThinKom’s antennas with independently pointable transmitter receivers can be exploited to use the best attributes of the orbits. 

“Think about using the GEO satellite for the forward link, but use a MEO or LEO satellite for the return link. This allows you to cut the latency in half and actually exploit the best attributes of both to the relative merits on the return link, and the forward link. We’re actually able to do that because these systems are very highly agile,” Milroy said.  

But Milroy said ThinKom doesn’t see the value in a multi-band, Ku- and Ka-band combined array, because both bands are worldwide capable in GEO and NGSO systems and a multi-band array brings too much added weight, cost, and compromise in performance. 

“There’s no free lunch. To get Ku- and Ka- you have to do something, the radome is more challenged, we don’t think it’s worth it,” Milroy said. “We think that folks who would buy a dual Ku-/Ka- solution would eventually regret [it]. … We’re an agnostic terminal supplier, they’re both great. And if you pick one based on whatever its merits are, you’ll be happy.”