4-40 GHz In-Phase/ 180^° Out-of-Phase Power Dividers with Enhanced Isolation

Abstract

This paper demonstrates a single topology to implement ultra-wideband in-phase and 180° out-of-phase power dividers which will be dedicated for ultra-wideband frontends and balanced antenna systems that require a decent amount of isolation between ports. Both power dividers are formed of two couples of microstrip-to-slotline transitions terminated with radial stubs and then cascaded with a multisection Wilkinson power divider. A parametric study of the microstrip-to-slotline transition is performed to identify the main parameters' influence on its frequency response, followed by a full-wave optimization. Both power dividers are designed on RO4003C substrates and both have the same size of × mm 2. Simulation results show that the power dividers can operate between 4 and 40 GHz with less than 6 dB insertion loss and with small amplitude and phase imbalances between output ports. And most importantly, both devices have at least 20 dB of isolation between output ports over the entire bandwidth.

3D-Printed Ultra-Wideband In-Band Full-Duplex Antenna System With Grating Lobes Reduction

“…Similarly, the metallic parts of the coaxial cables were also modeled as PECs, while the dielectric part of the coax was modeled as Teflon (𝜀𝜀 𝑟𝑟 = 2.1, tan 𝛿𝛿 = 0.0002). Moreover, two microstrip-slotline baluns operating in the frequency range from 2 to 20 GHz were also designed and simulated based on [6]. The results of the simulation are depicted in Fig.…”

“…The wideband performance of both the antennas and baluns can be attributed to the wideband behavior of the microstrip-slotline transitions used in both devices. And those transitions were optimized for maximum bandwidth based on a previous study [6].…”

Ultra‐wideband antenna system for in‐band full‐duplex applications

“…So the same transition will be used to feed the Vivaldi antenna, however, note that, a microstrip radial stub with half the size of that used in the balun is adopted here. The size reduction of the microstrip stub reduces the overlap with the slotline stub and, consequently, reduces the power leaked by the transition [33], which means that more power will be fed to the antenna, and this will enhance its efficiency.…”

“…Since the two output microstrip lines are oriented in opposite directions, the two output signals will be inverted with respect to one another over a wide bandwidth. The used balun was designed and optimised, in CST Microwave Studio, based on the parametric analysis performed by us in [33], after that, two baluns were fabricated on a 203.2 thick RO4003C substrate ( = 3.55), and they occupy an area of 40 mm × 40 mm.…”

Wideband Dual-Polarized Full-Duplex Antenna Array

“…The wideband performance of the balun is attributed to the wideband behavior of microstrip-to-slotline transitions. Those transitions can be matched over a decade bandwidth if they are terminated with radial stubs and tuned properly [11]. Moreover, the balun exhibits an insertion loss that increases from 6.24 dB at 2 GHz to 7.32 at 20 GHz.…”