Removing Grating Lobes in Sparse Sensor Arrays with a Nonlinear Approach

Epcacan, Erdal
Çiloğlu, Tolga
Candan, Çağatay
Mehmetcik, Erdal
Two of the most important criteria for a sensor array beam-pattern are beamwidth and side-lobe level. A narrower beamwidth means a better angular resolution and well separation of close sources. The beamwidth of a sensor array is directly proportional to array aperture, the beamwidth gets narrower as array aperture increases. However, increase in array aperture means increase in number of used sensors due to Nyquist spatial rate and this means increase in cost and computational load. Therefore, sparse arrays which violate Nyquist spatial rate are used. To cancel grating lobes occurred due to violation of Nyquist rate a weight optimization is implemented. In this paper, an approach which does not need weight optimization for grating lobe cancellation is presented. This method is inspired from nonlinear apodization (windowing) method. The necessary information to cancel grating lobes is obtained from a sub-array contained in the sparse array and this sub-array obeys Nyquist spatial rate.


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In this thesis, sparse linear sensor arrays have been studied. The study of sparse arrays in this work can be considered under two main headings: Analysis and comparison of recently proposed coarray based arrays, and the adaptation of the nonlinear apodization method for linear arrays and its use in sparse linear array design. Recently proposed coarray-based sparse arrays are designed with closed form structures without the need for any optimization and have much higher degrees of freedom (DOF) than a unif...
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Pattern reconfigurable antennas improve the performance of the system in applications which have dynamic radiation pattern requirements like multi- input multi-output arrays, phased arrays and body area networks. Characteristic mode theory was shown to be useful when investigating the possible orthogonal radiation patterns on an antenna element. Due to improvements in computation capacity of the modern computers, characteristic mode analysis can be used efficiently during the design of pattern reconfigurabl...
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Citation Formats
E. Epcacan, T. Çiloğlu, Ç. Candan, and E. Mehmetcik, “Removing Grating Lobes in Sparse Sensor Arrays with a Nonlinear Approach,” 2015, Accessed: 00, 2020. [Online]. Available: