Ku-band vs. Ka-band – What’s the Real Story?

Comparing Ku-band and Ka-band satellite capacity is a high interest topic right now in the satellite industry. In fact, a previous story we wrote on this topic is one of the best read pages on SATCOM Frontier.

A new study just released sheds new light on this important topic. Presented late last month at the International Conference on Satellite and Space Communications (ICSSC) 2012 in Rome, Italy, the study shows that the differences between Ku-band and Ka-band have much more to do with spot beam size than frequency band.

Ku-band currently dominates the aeronautical mobile satellite systems (AMSS) broadband market. The satellite bandwidth is leased by many companies from Fixed Satellite Service (FSS) providers like Intelsat and AMERICOM. These Ku-band satellites utilize continental scale wide beams.

New Ka-band systems coming onto the market promise to deliver substantially greater throughput than current Ku-band offerings. This fact has led some in the industry to conclude that Ka-band capacity is a superior evolution of Ku-band capacity.

However, this study demonstrates that the superior performance of Ka-band is the result of customized satellites and multiple spot beams. A Ku-band satellite using similarly sized spot beams can equal or exceed the performance of Ka-band satellites.

All this is not to say that one frequency is better or worse than the other. There are certainly scenarios in which Ka-band SATCOM is advisable. In fact, the new Intelsat Epic platform will offer C-, Ku- and Ka-band frequencies.

However, correcting the current misunderstanding of many around the performance characteristics of these frequencies is important. It could provide an evolution path to greater satellite capacity with current Ku-band satellites, thereby avoiding the need for expensive changes to terrestrial infrastructure.