Extremely wideband in‐phase power divider using modified Wilkinson design

Abstract

ABSTRACTA planar in‐phase power divider with extreme wideband behavior using modified Wilkinson design is presented. Instead of using T‐junction at the input port of the traditional design, the proposed divider uses broadside coupled microstrip to slotline configuration. Moreover, the impedance matching of the output ports is significantly improved across several octaves bandwidth using three binomial sections, whereas the isolation between those ports is enhanced across that band using three isolation resistors. The utilized structure is suitable for single layer integration as both the input and output ports are located at the same layer. A prototype of the presented device is designed using a proper theoretical approach, built, and tested. The developed device has a compact size with an overall dimension of 40 × 55 mm2 using the substrate Rogers RO4003 (dielectric constant = 3.38, thickness = 0.406 mm). While the device can be used for any wideband application, the developed prototype is designed to operate within the band 1–7 GHz, which is used in most microwave‐based medical imaging applications. The achieved simulated and measured results show that the proposed device has equal power division between the two output ports with less than 0.2‐dB amplitude imbalance, more than 10‐dB return loss and 15‐dB isolation, and less than 2° phase difference between the two output signals across the extremely wide frequency band 1.2–7 GHz. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1799–1802, 2015