COMSOL Study of ULA and NULA in the Presence of Mutual Coupling

Direction-of-arrival estimation has numerous applications ranging from defense to the entertainment industry. Traditionally, DoA can be estimated using Uniform Linear Array (ULA) which can process only N - 1 sources using N sensors. Recently, many NonUniform linear array has been designed to improve the accuracy and resolution limit. NULAs also reduce the effect of mutual coupling which enhances the accuracy of DoA estimation. Here, we have reported the performance analysis of ULA and various NULAs over the different environmental conditions such as in the presence of mutual coupling, correlated noise, etc. The received signals at the sensors for different environmental conditions and angular locations have been generated using the finite element analysis tool, i.e., COMSOL Multiphysics. We have compared the spatial spectra of ULA and NULA structures for single and multiple sources. Afterward, we have examined the estimation performance of ULA and NULA by considering the effect of mutual coupling for single and multiple sources. The experiment results show that the NULA provide better DoA estimation in both the condition, i.e., with mutual coupling and without mutual coupling. Besides, it can also find more number of sources than ULA with the same number of sensors.