Other forms of modulation also increase the signal bandwidth and enable range to be measured. Phase and/or frequency modulation (FM) may be imparted onto a CW signal for the measurement of range. In much the same way as pulsed modulation allows the time delay between the transmission of the signal and the reception of a target return to be established, so, too, does the use of phase or frequency modulation. The most commonly used form of modulation is a linear frequency modulation (LFM), and it gives rise to FM ranging in CW systems and high pulse repetition frequency (PRF) pulsed radars.

Chapter Contents:

• 10.1 Frequency Modulation Ranging in Continuous Wave Systems
• 10.2 FM Ranging in Pulsed Systems
• References

Inspec keywords: frequency modulation; CW radar

Other keywords: frequency modulation ranging; high-PRF; signal bandwidth; LFM; time delay; CW systems; signal transmission; pulsed modulation; high-pulse repetition frequency pulsed radars; linear frequency modulation; target return reception; range measurement; CW signal

Subjects: Radar equipment, systems and applications; Modulation and coding methods