Broadband planar 90 degrees loaded-stub phase shifter

• Published in: Telkomnika Vol. 18; no. 6; pp. 2834 - 2841
• Main Authors: Marini, S. El, Mandry, R., Zbitou, J., Errkik, A., Tajmouati, A., Latrach, M.
• Format: Journal Article
• Language: English
• Published: Yogyakarta Ahmad Dahlan University 01.12.2020
• Subjects: Bandwidths; Broadband; Design; Design analysis; Electrical impedance; Frequencies; Mathematical analysis; Phase shifters; T shape; Transmission lines; Ultrawideband
• ISSN: 1693-6930; 2302-9293
• DOI: 10.12928/telkomnika.v18i6.15691

[...]these designs are so intricate and still require a narrow gap between the coupled lines, especially at the ultra-wideband frequencies. Besides Schiffman configurations, broadside coupled structures is another way to realize broadband phase shifters. In this letter, a novel design of broadband phase shifters exploiting three open stub-loaded transmission line is investigated, detailed theoretical analysis, and design equations are given. [...]one broadband 90° phase shifter highly suitable for applications in L and S bands is designed employing a combination of 0.5λ transmission line with three T-shaped stepped-impedance open stubs 2. The optimal admittance Ys to obtain flat differential phase response within the frequency band ranging from 0.5 to 1.5 f0, can be calculated using (7), Figure 2 (a) shows the calculated admittance for differential phase shifts of 45°, 60°, 75°, 90°, 105°, and 120°. Since the admittance Ys is obtained from (7) as shown in Figure 2 (a), then the return loss of the main line expressed in (3) can be simplified to: According to the analysis mentioned above, the design process is both clear