In chapter 12, we explore how a radar determines range. We have already covered in chapter 1 the basic idea behind determing range: the time delay for a radar pulse to get to a target at range R and return is
t = 2R/c.
We have seen that this gives the correct result for unambiguous PRFs. In most situations, we need the higher average power gained by using a higher PRF. Your text in this chapter explains how ranging can be done successfully with carefully chosen ambiguous PRFs.
The problems for this chapter will cover the techniques used for ranging in MPRF radar operation. In MPRF operation, there are many ambiguities which must be resolved to determine range. A typical MPRF radar must resolve 10 to 50 ambiguities to determine the correct range.
We have already covered LPRF ranging. To gain a complete understanding of radar ranging, you must also understand how ranging is done in HPRF operation. HPRF Ranging is treated in Chapter 14.
A helpful tool is available for calculating the relationship between distance, time, and frequency in a pulsed radar system. Link to the timing calculator to experiment or solve some problems.
Spreadsheets will help with the problems in this chapter and will allow you to explore this type of problem further.