I learnt that satellite can be equipped with transponder of different bands (L, C, Ku, Ka), and in term of bandwidth, L < C < Ku < Ka. My question is, am I correct to assume that, with a higher bandwidth, the equipment cost should be higher? i.e. Ka band transponder should be the most expensive and L band transponder is the cheapest. And a satellite equipped with only L band transponders should be cheaper to develop that that equipped with Ka band transponders. Thank you.

  • $\begingroup$ This is a good question - but do you mean only the cost of the transponder in the satellite itself, or the cost of one or many ground stations that must also operate on the same bands. Many times uplink and downlink can be in different bands as well. $\endgroup$ – uhoh Aug 11 '16 at 4:38
  • 1
    $\begingroup$ I mean the cost of development for transponder in satellite itself, and the cost of satellite equipped with Ka band compared with that of L band as a whole. Thanks. $\endgroup$ – Stephen Chung Aug 11 '16 at 4:53
  • $\begingroup$ In general, the higher the frequency, the more difficult (and more expensive) it becomes to design a circuit that works well at that frequency. I don't have numbers though. $\endgroup$ – Hobbes Aug 11 '16 at 10:17

Hobbes is correct. Higher frequency transponders are more expensive to design and test than low frequency transponders. This is simply because as the wavelength decreases, smaller components within the transponder will have an effect (often unintended). You can build a VHF or UHF radio using a handful of cheap parts. The flip side of this is that higher frequency bands contain more bandwidth, so it is relatively easier to obtain the rights to a large chunk of Ka band than it would be in C or S band.

The transponder is often just a fraction of the entire mission, so it's cost is usually insignificant or minor in comparison to other costs. Also, since higher bandwidth satellites can deliver more data to more users, the cost of the transponder is quickly repaid. Think about the number of users dish satellite has and the revenue they generate.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.