DOA Estimation Using Antenna Arrays: A Universal Array Designing Framework

The use of antenna arrays is pivotal in array signal processing, with the different antenna arrays having their own structural advantages. The uniform linear arrays (ULAs) are more robust against antenna failures, but their degrees of freedom (DOFs) and array aperture, which are crucial for the direction of arrival (DOA) estimation, are limited. On the other hand, the sparse arrays can offer more DOFs and a larger array aperture but may not necessarily be as robust as ULAs. Hence depending on the given requirement, the properties of certain antenna arrays need to be exploited for direction finding. However, most of the existing antenna array configurations are deprived of a universal design approach. This manuscript introduces a universal array designing framework (UADF), which can employ different antenna arrays and exhibit multiple desirable properties. The UADF is based on effectively cascading three identical levels that can be nested to another
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-times, with only its initial level to be configured by the antenna array. Thus, it inherits the characteristics of configuration used in the initial level and simultaneously embeds a good balance between key features in terms of low cost, easier construction and extension, reliability, robustness, more DOFs, larger continuous virtual aperture, and higher spatial efficiency. Moreover, the UADF enjoys closed-form expressions for the array configuration and DOFs. We employed different antenna arrays to demonstrate the usefulness of UDAF, which is also confirmed via numerical experiments.