Abstract|The experimental validation of reduced grating lobes in a seven-element, hexagonal, scanning phased array antenna with the one-wavelength element spacing is presented. The base element of the array is a single-layer, dual-mode antenna with self-scanning and nulling properties. For the selected scan angle of ¡30±, the required microstrip transmission line based feeding network, consisting of ring hybrids, power splitters, and branchline couplers, are designed and developed. A prototype of the complete array and feeding network was fabricated and successfully tested to show the e®ectiveness of the grating lobe reduction method using the dual-mode antenna elements in scanning phased array antennas with the one-wavelength element spacing.
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Grating Lobe Mitigation in Scanning Planar Phased Array Antennas
This paper presents the grating lobe reduction in a planar phased array antenna with a rectangular lattice and large element spacing in the order of one wavelength for scan angles up to ±45°. A dual-mode circular microstrip patch antenna is considered as the constitutive element of the phased array, in which two different transverse magnetic modes are exploited simultaneously. The numerical analysis shows that the achieved grating lobe reduction is well below 25 dB for scan angles up to ±45° with large element spacing in the order of one wavelength.
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- Award ID(s):
- 1653915
- PAR ID:
- 10211330
- Date Published:
- Journal Name:
- 2019 IEEE International Symposium on Phased Array System & Technology (PAST)
- Page Range / eLocation ID:
- 1 to 3
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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