Angle Accuracy of Antenna Noise Corrupted Ultra-Wideband Monopulse Receiver

In the ultra-wideband monopulse receiver, the incident signal is received with two receiving antennas in sum and difference mode. The received signals' phase and energy are then compared to find the incident signal. The received signals, however, are susceptible to antenna noise. In this paper, we establish the relationship between the angle accuracy of the proposed receiver and the signal-to-noise ratio. The receiver modeled in this paper consists of two co-located ridged-horns, with their sum/difference signals received by cross-correlation receivers and processed by an ideal amplitude-comparison monopulse processor. The derived angle accuracy is compared with monopulse measurements at angles-5° to +5° at 1° intervals. Measurements verify the derivations, showing a root-mean-square error of 0.43° (measured) vs. 0.46° (theoretical) at boresight; 0.13° (measured) vs. 0.09° (theoretical) at -5°; and 0.17° (measured) vs. 0.09° (theoretical) at +5°.