Comparative study of the radiation characteristics between uniform, Tschebyscheff and Binomial amplitude distributions of linear patch antenna array for x-band radar warning receivers

In antenna arrays, the excitation amplitude of the individual elements is one of the major controls that can be used to shape the overall pattern of the antenna. In this paper, 1×10 rectangular patch antenna array is designed and simulated at 9.5 GHZ on specific microwave laminate using uniform, Dolph-Tchebyscheff and Binomial amplitude distributions for specific spacing between elements. The particular spacing are 0.5λ, 0.6λ, 0.8λ and 0.9λ. For each spacing: radiation pattern, beam width, gain, directivity, radiation efficiency and side lobe level are critically investigated and compared for each distribution to justify its usage for radar warning receivers. Simulation is done using ADS 2009 software from Agilent Company. From simulation results, of the three distributions (uniform, binomial, and Dolph-Tchebycheff), a uniform amplitude array yields the smallest half-power beam width. It is followed, in order, by the Dolph-Tchebyscheff and binomial arrays. In contrast, binomial arrays usually possess the smallest side lobes followed, in order, by the Dolph-Tchebycheff and uniform arrays. It is also found that for 0.9λ spacing, DolphTchebyscheff has better efficiency (82.4%), better side lobe level (-32.7 dB) and gain of 16.1 dB with beam width of 7 degrees which makes it the best antenna array solution for RWR systems between the other distributions that have been investigated in this work.