[amsat-bb] Digital Satellites Question

[Phil Karn]

On 07/22/2014 08:50 AM, Douglas Phelps wrote:
> And, in a related question, wouldn't more proccessing demand more
> power from the batteries/solar panels?  I know my PC cetainly draws a
> lot more power when the CPO is working hard.

Not really. The biggest load in a communications satellite, or almost
any robotic spacecraft for that matter, is almost always the downlink RF
power amplifier(s). Using them more efficiently can justify almost anything.

Also, even highly efficient digital modes tend to be easy to generate;
many spacecraft do (or did) so purely in hardware. Demodulating and
decoding them is more work so uplink and downlink modes are often
different, each optimized for its purpose.

--Phil