Ehsan ZAREIAN-JAHROMI, Raheleh BASIRI, Parvin SALEHI, Hamidreza KARAMI

Improving side lobe level of X-band microstrip Rotman lens utilizing nonuniform distribution of output ports

A new microstrip Rotman lens with enhanced side lobe level (SLL) is proposed for X-band applications. A proper nonuniform distribution of the initial width of output ports is considered to improve the SLL. The benefit of SLL improvement is not based on using additional attenuators or amplifiers at the output ports. Moreover, an analytical background is presented to investigate the resulting SLL of the proposed structure. The advantage of SLL enhancement is obtained at all noncorner scan angles considering 10 GHz operating frequency. As the middle input port is excited, more than 3 dB of SLL enhancement is achieved at 10 GHz. The proposed structure provides even more accurate scan angles than those of the conventional Rotman lens. The designed structure is simulated using full-wave HFSS 15 software. The comparison between simulated results and measurements of the fabricated proposed Rotman lens shows good agreement.

Keywords:

Antenna arrays beam forming network, beam steering, side lobe level improvement, Rotman lens,

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Turkish Journal of Electrical Engineering and Computer Science-Cover

ISSN: 1300-0632
Yayın Aralığı: Yılda 6 Sayı
Yayıncı: TÜBİTAK

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