# Homework Help: Pulse doppler radar: resolution of speed measurements

1. Aug 30, 2011

### KanedaSyndrom

1. The problem statement, all variables and given/known data

Parameters:
Carrier frequency: 5.3*10^9 Hz
Pulse length: 20*10^-6s
PRF: 30*10^6Hz

2. Relevant equations

The question is this:

"100 pulses are reflected from a moving target and received by the radar.

-What is the resolution of a speed measurement determined from these measurements?
-Can a speed of 100 km/h be measured unambiguously?

3. The attempt at a solution

Not much of an attempt because I'm in doubt at a solution since no equations was given in the lecture slides beyond the standard doppler shift formula of:

fd= -fc*2*vr/c

Where,

fd= doppler shifted frequency of the carrier frequency
fc= carrier frequency
vr=movement speed of target, probably in km/h I suspect, but not sure if this is in m/s which would make sense I think.
c= propagation speed of electromagnetic radiation in vacuum.

I'm a bit rusty in this, I knew the answers a few semester ago, but wouldn't hurt getting other eyes on the problem, which is quite simple.