Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Pulse doppler radar: resolution of speed measurements

  1. Aug 30, 2011 #1
    1. The problem statement, all variables and given/known data

    Pulse radar:

    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


    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.
  2. jcsd
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted