Statistical Analysis of the Effect of Phase Quantization on Array Antenna Sidelobes.

摘要

General expressions for the mean and variance of the power at an arbitrary location in the pattern are derived for a linear array of isotronic equispaced elements. The phases of the element excitation coefficients are assumed to be set by digital phase shifters, causing random phase errors uniformly distributed in the interval of plus to minus the least significant bit of the phase command. Approximations valid for small phase errors (N bit > 4) are obtained. For large arrays, the variance of the power at a location where the error-free pattern has a null is approximately equal to the square of the mean of the power. The theoretical results are compared with Monte Carlo computer simulations. The Kolmogorov-Smirnov test usually shows close agreement between the simulation and the theoretical results. However, the test also shows that the depths of multiple nulls are not statistically independent when there are multiple nulls in the error-free pattern; the probability distribution of the depth of the least deep null is closer to the distribution predicted for a single null than it is to the distribution for multiple nulls. (Author)