Pattern Model of Phased Array Antenna Based on Field Strengths Superposition

Aiming at the situation that single frequency and constant amplitude signals are usually used to deduce,simulate and analyze radiation patterns of PAA(phased array antenna),the mathematic model of PAA patterns based on emitting LFM(Linear Frequency Modulation)signals is proposed.The model utilizes the method of field strengths superposition to deduce PAA patterns,expressing the property of far field patterns by complex envelopes of synthetic field strength.It also analyzes the basic pattern characteristics and beam scanning patterns of phase controlling.The MATLAB simulation results indicate that the LFM patterns of PAA generated by this model have narrow main lobe and low side lobe,which agree with actual situation.Under the condition that the LFM amplitudes are constant within the LFM signal duration,complex envelopes of PAA patterns have changing phases and constant amplitudes.The research results provide theoretical basis for phase control schematic design and error analysis of PAA emitting LFM.