A Broadband Magnetic Coupling Microstrip to Waveguide Transition Using Complementary Split Ring Resonators

Abstract

A novel broadband microstrip to waveguide transition is proposed in this paper. A microstrip circuit is inserted into a waveguide along the axis of the broadside wall, and the referred waveguide is WR-90 standardized rectangular waveguide. The microstrip circuit consists of a pair of symmetric step-like patches, a microstrip probe, and a metal ground plane. The transition has a smaller size as it is end-inserted. Meanwhile, the traditionally stepped metal ridge in the waveguide is replaced with bistratal symmetric patches, integrated design of patches, and microstrip probe. Therefore, the welding loss and structural instability have been avoided. Complementary split ring resonators are loaded in the patches to broaden the bandwidth and increase efficiency. Measured results show that the proposed microstrip to waveguide transition achieves a −15 dB return loss with the bandwidth of 8.65-12.33 GHz, and its insertion loss is better 0.5 dB over the band of 8.13-12.13 GHz. Furthermore, this design features lightweight, low cost, and simple processing methods. INDEX TERMS Microstrip to waveguide transition, complementary split ring resonators (CSRRs), end-inserted transition.

A Dual-Band Compact Four-Port Mimo Antenna Based on Ebg and CSRR for Sub-6 GHZ Applications

“…On the one hand, CSRR is a ubiquitous meta-structure widely used for adjusting the impedance parameters of the metal patch for better matching. On the other hand, when the CSRR is excited, there is a capacitive effect on the external and internal metal of the structure, and at the same time, there will be an inductive coupling effect between the two structures, resulting in an obvious electrical resonance effect and an electromagnetic stopband [9]. In order to further ameliorate impedance matching, a new L-shaped structure of CSRR is introduced in the ground plane to contribute to the radiation in antenna 2 by guiding surface wave propagation.…”

An Economic Low-profile Elliptical Microstrip Antenna-to-RWG Transition for Microwave Laboratory and X-Band Applications

“…The microstrip lines (MSL) are increasingly being used to build hybrid and monolithic circuits (MICs), which has necessitated the creation of an interface that connects waveguides and MSL [1]. Microstrip line to rectangular waveguide (RWG) transitions come in a variety of forms, including inline (0˚) [2][3][4][5][6][7][8], out-of-line (90˚), E-plane, and H-plane transitions [9][10][11][12][13]. All transitions differ from each other by the way they share/couple their energy [14].…”

“…Al., have demonstrated an inline X-band transition to broaden the bandwidth and increase efficiency. The microstrip probe complementary split ring resonators (CSRRs) were loaded into the patches for this purpose [2]. By keeping all the literature in mind this work presents a low-cost, compact, waveguide length invariant MSL-to-RWG transition for laboratory, space, and satellite communication, RADAR, Amateur Radio, front end connector for transmitter/receivers; MMIC/MIC circuits interconnect for X-band application.…”

Implementation of left handed transmission lines based on waveguide TM modes

“…The characteristics for the CSRRs including their equivalent‐circuit models have been studied and explained extensively 17–19 . The implementation of LH TL using rectangular waveguide TE10 mode and SRR has been proposed 20–28 …”

“…[17][18][19] The implementation of LH TL using rectangular waveguide TE10 mode and SRR has been proposed. [20][21][22][23][24][25][26][27][28] The main novelty of this work is to introduce TM mode and CSRRs simultaneously to achieve high-Q and feasible double negative passband below the cutoff. Figure 1 summarizes the different combination of waveguide and SRR/CSRR and their related character.…”