سال انتشار: ۱۳۹۰

محل انتشار: نوزدهمین کنفرانس مهندسی برق ایران

تعداد صفحات: ۵

نویسنده(ها):

Rasool Keshavarz – Electrical Engineering Department, Shahid Bahonar University of Kerman, Kerman, Iran
Mostafa Danaeian –
Masoud Movahhedi –
Ahmad Hakimi –

چکیده:

A dual-band (DB) microstrip branch-line coupler with quadrature phase difference based on the interdigital transmission line (TL) is presented. Interdigital TLs are realized by cascading interdigital capacitors (cells of the structure) in series. The design procedure to reach the dual-band interdigitaltransmission lines at two arbitrary frequencies is presented. Dual-band operation for branch-line coupler is achieved by implementing the interdigital TLs with 3 cells in each branch to provide a phase of – 900 at the lower operation frequency band (2GHz) and – 2700 phase shift at the upper frequency band(3GHz). Branches length is approximately g λ ۰٫۸ and as compared to the conventional DB composite right/left handed (CRLH) branch-line couplers, the proposed structure achievessmaller dimension. Also, simulation results show that the dualband proposed coupler exhibits an amplitude balance of ±۲ dBfrom 1.9 GHz to 2.2 GHz in the lower band and from 2.8 GHz to 3.2 GHz in the upper band. Moreover, at mentioned frequency bands, the phase difference between the coupled and through ports is 900 ±۱۰۰