PULSE CHARACTERISTICS

PULSE CHARACTERISTICS

1. Wavelength

   • directly related to beamwidth
     • short wavelength = narrow beam

2. Amplitude

   • Directly related to power
     • High waves = more power

3. Frequency

   • Wavelength and frequency are related
     • decrease wavelength = frequency increase
     • Frequency = c/wavelength

4. Pulse length

   • measured from leading edge to back
     • Pulse length = power
     • Pulse length - range resolution
     • Ideal to have short powerful pulses

5. Pulse Repetition Frequency (PRF

   • Max Unambiguous range
     • greater PRF = shorter unambiguous range
       • Rmax = c/2PRF
   • Listening Time
     • The wait between pulses
       • determined by PRF
   • Antenna Motion
     • Revolution per min
       • increase PRF if rotation is faster
   • Dwell Time
     • Dwell = target presentation
       • PRF = Dwell time
   • Range Folding (Second-Trip Echoes)
     • 1/2 distance traveled
       • Azimuth is good, but range is wrong
         • Typical elongated