EVALUATION AND IMPROVEMENT OF RADAR BEACON SYSTEMS.
Final rept. 1 Jun 62-31 May 64,
IIT RESEARCH INST CHICAGO IL
Pagination or Media Count:
A previous analysis of the Doppler errors due to beacon antenna rotation, based on a manual Fourier series analysis, has been refined by utilizing a digital computer to precisely calculate 1 the resultant phase of the three-slot antenna, 2 the instantaneous rotational Doppler shifts seen by the coherent radar, and 3 the effect the frequency tracking loop of the FPS-16 coherent radar has in smoothing the input Doppler errors. It is shown that beacon rotation rates of up to one rotation persecond introduce velocity errors of up to sixty times greater than any other error present in the system. Higher rotation rates force the tracking loop into a transition region which ultimately leads to non-linear operation. A summary and review is presented of work in the following areas 1 coherent pulse-radar tracking modifications and characteristics, 2 parameters and design specifications of a coherent beacon, 3 oscillator phase and frequency errors, 4 filtering of velocity errors due to frequency instability, and 5 spectrum broadening due to frequency instability. Theory and experimental results of C-band guide, and stepped guide tunneldiode amplifiers are presented. Particular emphasis is placed on stability criteria for these amplifiers. The dc biasing circuit of C-band tunnel-diode amplifiers is analyzed and tested experimentally. The effect of instability in the biasing circuit is discussed. Author