Elementary search radars employ a continuous periodic pulse transmission with a rotating antenna. As the antenna scans across a target, the amplitudes of both transmitted and received pulses are modified by the antenna beam pattern; this converts the uniform periodic pulse train generated by the radar transmitter to an amplitude-modulated pulse train of finite duration. The pulse train duration is determined by the antenna scan rate and beamwidth; the number of pulses in the train is a function of both train duration and the radar pulse repetition frequency. Pulse-train amplitude modulation results in a variation of received pulse signal-to-noise ratio as a function of time. In previous chapters, optimum receiver processing and performance were investigated for uniform pulse trains; these results are extended to amplitude-modulated trains in this chapter.

Chapter Contents:

• 15.1 Introduction
• 15.2 Implementation
• 15.3 Parameter Optimization
• 15.4 Performance Evaluation
• 15.5 Detection Probability for Uniform Integration of Constant Amplitude Pulses
• 15.6 Detection Probability for a Single Loop-Integrator Assuming a Gaussian Pulse Train Envelope
• 15.7 Detection Probability for a Double-Loop Integrator Assuming a Gaussian Pulse Train Envelope
• 15.8 Comparison of Single- and Double-Loop Integrators
• Problems
• References

Inspec keywords: radar antennas; amplitude modulation; search radar

Other keywords: uniform periodic pulse train; amplitude-modulated pulse train; elementary search radars; continuous periodic pulse transmission; received pulse signal-to-noise ratio; weighted integrators; radar transmitter; antenna scan rate; rotating antenna; finite duration; antenna beamwidth; antenna beam pattern; transmitted pulse amplitude; pulse train duration; received pulse amplitude; radar pulse repetition frequency; pulse-train amplitude modulation

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