In sci.physics Hal Murray wrote:
No, but I have enough years of experience with RF in general and radar
in particular to know building a phased array requires precise phase
(or frequency) control and you can't do that with an ultra wideband
device, which has a bandwidth of 500 Mhz.

What is the bandwidth of modern radars? I'd expect it to be
wide and using spread spectrum tricks to make jaming harder.

Depends on what bandwidth you are talking about.

For the instananeous transmitted frequency, narrow.

Some military stuff has used frequency hopping since WWII to make it
harder to jam.

Frequency hopping is a spread spectrum technique and the bandwidth
over time is wide.

You could make a spread spectrum, phased array radar, but the frequency,
phase, and amplitude of all the emitters has to be precisely controlled
to form the beam, which implies that for a given pulse, all the
emitters are transmitting very close to the same frequency.

The next pulse may be hundreds of megahertz away, but that's what
processors are for.

--
Jim Pennino

Remove .spam.sux to reply.