On 12/18/2017 04:34 PM, Henry Spencer wrote:
The current high-end "in vogue" techniques all involve DSP with arrays of coherent receivers, and beam-forming in DSP in FPGAs, or in Software, depending on
Yes, in principle, although the implementation can get complicated. It's called a phased-array antenna.
If you want to do all the combining in software, that means you need a separate receiver for each antenna. It is usually considered preferable to have a controllable phase shifter behind each antenna and combine the signals electronically immediately after that, so they can go into a single receiver, but some systems do postpone the combining. (One reason for doing so is that you can then do the combining in multiple different ways to receive from several sources simultaneously.)
There are limits to this -- in particular, the farther off the centerline you try to "point the beam", the broader and sloppier the beam, and hence the poorer the receive performance.
Henry
