Efficient Computation of Array Factor and Sidelobe Level of Linear Arrays [EM Programmer's Notebook]

The implementation of code to efficiently compute the array factor and sidelobe level (SLL) of linear antenna arrays in MATLAB and GNU Octave is considered in this article. The use of a fast Fourier transform (FFT) to compute the array factor is shown to be more efficient than other approaches. The automatic determination of the sidelobe region as a necessary step to computing the SLL is addressed. A number of code-optimization techniques in MATLAB and Octave are evaluated, including vectorization, memory allocation, and the use of built-in functions. Finally, an efficient function that can be used for the computation of the array factor and SLL of linear arrays in MATLAB and Octave is presented.