AP 3302 Pt. 3
Section 1
CHAPTER 3
Factors affecting the performance of Pulse-Modulated Radars
Pulse
Duration
The pulse duration selected for a particular radar depends upon several factors, the most important being summarised below:
a. Minimum range. The time interval equivalent to one radar mile is10.75 us. Thus if we are using a pulse duration of 10.75 us any target at a range less than one mile will not be seen because the transmitter will still be firing when the target echo arrives back at the aerial.
Since the aerial is still connected by the T-R switch to the transmitter the echo will not provide any input to the receiver (Fig 19). Short-duration pulses are needed for short-range working.
