Grating Lobe Suppression Method Based on Pattern Sampling and Frequency Conversion Multiplication

Distributed arrays produce a large number of grating lobes in the pattern due to the large spacing of the array elements, which leads to ambiguity in the angle estimation and enhanced interference signals strength. Traditional methods (such as optimization algorithms, virtual array element interpolation) have the defects of poor grating level performance, high computational complexity and limited freedom of optimization. However, the existing frequency conversion technology can adjust the grating lobes position, eliminate the grating lobes, but it is easy to sacrifice the performance of the main lobe or rely on complex hardware. To solve the above problems, this paper proposes a grating lobe suppression method based on pattern sampling and frequency conversion multiplication. By dynamically changing the signal frequency to adjust the grating lobes position, combines the complementary characteristics of the grating lobes position at different frequencies, and uses the multiplication of the patterns to eliminate the grating lobes, and at the same time, introduces the Woodward-Lawson sampling method to generate deep null to further suppress side lobe. Finally, the effectiveness and advancement of the algorithm is verified through simulation experiments.