Generation of flexible pulse compression waveforms with computer control

Alternate approaches for a pulse compression waveform generator that can synthesize a general class of coherent waveforms for modern radar systems are compared in terms of cost, complexity, and circuit performance requirements. Equipment was prepared and performance tested for three systems which represent (1) a direct synthesis approach where the computation and control of a synthesizer are accomplished in real time; (2) a synthesis approach where the computation is performed off-line, and the control data is stored in memory ready to be used for real-time synthesizer control; and (3) a phase-locked loop approach where the computation of the loop reference signal is performed off-line, and the reference phase data is stored in memory for use in real-time signal control. Computer simulation tests support the conclusion that the PLL-controlled voltage-controlled oscillator waveform generator is the most advantageous approach.