The Simulation Method Of Phased Array Antenna Radiation Pattern Using Spatial Filtering

The element structure of phased array antenna is complicated, and its radiation pattern changes according to the variety of scan angle. Therefore, how to simulate the radiation pattern of phased array antenna correctly and instantaneously becomes a key problem in the simulation of phased array radar. In addition, as the electronic environment of radar becomes more and more complex, spatial filtering is utilized more and more widely in phased array radar system. Then, how to take advantage of the spatial filtering ability in the simulation of radiation pattern is also a problem that attracts our attention.In this paper, we give some primary analysis of spatial filtering, and simulation results are provided. We propose an instantaneous simulation method for radiation pattern and discuss primarily how to take advantage of the spatial filtering ability in the simulation of radiation pattern.Firstly, we introduce the fundamental principles of spatial filtering and perform some simulation. The principles, criteria and algorithms of adaptive beamforming are analyzed, and a special form of adaptive array, the sidelobe cancellation system, is analyzed in detail. The effect of target and the mainlobe jamming on sidelobe cancellation is discussed. And using block matrix as a solution, the form of block matrix when the auxiliary array is line array and area array is provided. Taking the the patriot radar system as an example, how the number, power and relative position of jamming, along with the receiver noise can affect the cancellation is analyzed. Finally, the jamming method is discussed primarily.T As the shape invariance of phased array antenna radiation pattern in sine-space coordinate system, considering the variety of antenna gain and beam width with beam scanning, a simulation method of fitting and approximation is proposed. A simulation method of the pattern which is not circinal symmetric is also proposed. At last ,it takes the antenna of GBR radar system and AN/SPY-1 radar system for example to do the simulation experiment.. The simulation results for GBR radar antenna and AN/SPY-1 radar antenna are provided.Finally, based on the analysis of the beamforming principle in phased array radar system, we discuss how to take advantage of the spatial filtering ability in the simulation of radiation pattern. For adaptive array, it is possible to realize the spatial filtering ability at subarray through subarray division. As for the sidelobe cancellation system, its simulation method is different because of its particularity. We can calculate the sum-and-difference beam pattern of main array first, and then get the adaptive weighted coefficients of auxiliary array .according to jamming angle through adaptive algorithms, and finally perform cancellation to obtain The sum-and-difference beam pattern.