Substrate Integrated Waveguide Phase Shifter Research Articles

Electronically Controlled 35-bit Substrate Integrated Waveguide Phase Shifter

Electronically Controlled 35-bit Substrate Integrated Waveguide Phase Shifter

Phase Shifting Enhancement of a Substrate-Integrated Waveguide Phase Shifter Based on Liquid Crystal

A novel technique to enhance the phase shifting range of a liquid crystal (LC)-based, substrate-integrated waveguide (SIW) phase shifter by inserting inductive posts (IPs) is presented for the first time. The IPs inserted in the LC-based SIW phase shifter produce a phase advance based on the relative permittivity of the LC, resulting in an additional differential phase shift. At 28 GHz, the proposed structure with IPs achieves a ratio of maximum differential phase shift (∆ϕmax) to maximum insertion loss (ILmax) (FoM1) = 52.82 °/dB and ratio of maximum differential phase shift to length (FoM2) = 2.62 °/mm. Compared with conventional LC-based SIW phase shifters that lack an IP and use the same amount of LC, the FoM1 increased by 16% and the FoM2 increased by 55%. In addition, compared to the typical structure that uses additional LCs instead of IPs, the FoM1 decreased by 7%, and FoM2 increased by 21%. Therefore, inserting IPs into the LC-based SIW phase shifter can reduce the dimensions of the phase shifter and the amount of LCs required to achieve the desired differential phase shift. We believe this work can contribute to the design of compact and efficient SIW phase shifters for future telecommunication systems.

A Balanced Substrate Integrated Waveguide Phase Shifter with Wideband Common-Mode Suppression

In this paper, a slotted substrate integrated waveguide (SIW) is used to create a balanced phase shifter with wideband common-mode (CM) suppression. Differential-mode (DM) impedance matching and CM suppression are achieved by utilizing the fact that TE20 mode and TE10 (TE30) mode can only transmit DM signals and CM signals, respectively, and by increasing the bandwidth for CM suppression via slots. Furthermore, a wideband phase shift with low phase deviation can be obtained due to the phase slop counteract between the slot and the delay line. Compared with the state-of-the-art, the proposed one has the advantages of wideband CM suppression, wide phase shift range, and a simple and easy-to-make structure. Five prototypes covering the frequency of 3.5 GHz are designed with the relative operating bandwidth for 45° ± 2° (90° ± 4.5°, 135° ± 6°, and 180° ± 8°) phase shifter of 20% (20%, 20%, and 20%), with the minimum insertion loss of 0.41 dB (0.5 dB, 0.58 dB, and 0.59 dB), with the minimum return loss greater than 15 dB, and with the relative bandwidth for 15-dB CM suppression of 59% (59%, 58%, and 57%).

Broadband and compact folded substrate integrated waveguide phase shifter and its application to 180° directional coupler

Abstract In this paper, a broadband, low insertion loss, and compact folded substrate integrated waveguide (FSIW) phase shifter is proposed for the first time. By loading the complementary split-ring resonators (CSRRs) on the middle metal layer of the FSIW, a closed-type slow-wave transmission line (TL) is obtained, which can provide a wideband phase shift (39%) compared with the equal-length fast-wave one. The enclosed structure of the CSRR-loaded FSIW prevents the CSRRs from radiation as suffered in the previous reported CSRR-loaded TLs, resulting in a low insertion loss. This feature greatly reduces the amplitude imbalance between the main line and the reference line of the phase shifter. In addition, no transition structure is required between the FSIWs with and without CSRRs for broadband impedance matching, which makes the phase shifter more compact and easier to integrate with other FSIW devices. To validate the performance of the proposed phase shifter and to illustrate its ease integration, a novel FSIW 180° directional coupler that consists of an FSIW 90° coupler and an FSIW 90° phase shifter is designed, fabricated, and measured. The measured results agree well with the simulated data.

Reconfigurable Phased-Array Antenna Using Continuously Tunable Substrate Integrated Waveguide Phase Shifter

A low-cost $1 \times 4$ phased array incorporating continuously tunable substrate integrated waveguide (SIW) phase shifters is presented in this paper. Through seamless integration between antenna elements, phase shifters, and an SIW feeding network, the proposed phased array is assembled in a multilayered monolithic structure. To obtain a wide phase variation range, the electronically controllable phase shifter is constructed by introducing varactor diodes into a reflection-type architecture, which can also offer a simple solution to constitute the biasing circuit of the diodes. Due to the merits of adequate bandwidth and good radiation performance, an aperture-coupled patch antenna with multi-resonance characteristic is selected as the array element. Accordingly, a prototype of the proposed phased array was fabricated by applying standard printed circuit board (PCB) facilities. The measured results demonstrate that a continuous beam scanning range from −45° to 45° covering the whole operating band of 5.09–5.98 GHz is obtained. Meanwhile, a gain of up to 11 dBi and an impedance bandwidth of 16.1% are achieved. Owing to the features of continuous wide-angle steerable beam, easy fabrication, and integration, the proposed phased-array antenna is attractive for 5G Wi-Fi applications.

Novel Substrate-Integrated Waveguide Phase Shifter and its Application to Six-Port Junction

A complementary split-ring resonator (CSRR)-loaded substrate-integrated waveguide (SIW) phase shifter and its application to a six-port junction is presented and demonstrated in this article. Different from the prior evanescent-mode analysis, this article concentrates on the TE10-mode analysis of CSRR-loaded SIW, and a slow-wave effect is observed. The CSRR offers a simple resolution to a slow-wave structure in SIW and can be verified by the CSRR equivalent-circuit model theory. Hence, an equal-length wideband 90° phase shifter (35%) can be realized by a proper design of the fast-slow-wave hybrid transmission line (TL). The phase velocity decrease caused by the slow-wave effect contributes to the length reduction of the phase shifter as well and makes it more compact. Furthermore, the widespread application of CSRR also helps generalize the slow-wave effect, and a more compact phase- shifter-based half-mode substrate-integrated waveguide (HMSIW) is obtained. To experimentally validate this concept, a dual-layer six-port- junction-based HMSIW is designed, simulated, and fabricated. The application of the slow-wave TL in a six-port design helps in the bandwidth enhancement and size reduction of the component, which makes it more applicable to demanding systems with complex requirements such as detecting and transceiver systems. The measured results are in accordance with the simulated data.

3-D empty substrate integrated waveguide phase shifter with equal length

3-D empty substrate integrated waveguide phase shifter with equal length

Characterization of a 4 × 4 substrate integrated waveguide Butler matrix at 60 GHz for two‐dimensional beam steering

A 4x4 substrate integrated waveguide (SIW) Butler matrix for two-dimensional (2-D) beam steering operating at 60 GHz is developed and experimentally evaluated in this article. The SIW beamforming network is a Butler matrix that is implemented with new designs of its constituent components in order to achieve a compact design. Namely, an SIW phase shifter that uses periodic rectangular slots is introduced for the first time at 60 GHz to replace the more area-consuming meandered SIW. The phase shifter prototype, fabricated and measured as a proof of concept, demonstrates achieving an additional 20.3° of phase shift with using only 3 apertures without increasing the length or meandering the SIW line. The hybrid coupler and crossover sections of the SIW Butler matrix are also optimized to reduce the overall area of Butler matrix by 53.9%. The SIW Butler matrix prototype is fabricated and measured demonstrating achieving the differential output phase values needed to switch the beam of a 2-D array in four quadrants while keeping the insertion loss magnitude imbalance of below 1.47 dB from simulations and 3.34 dB from measurements.

A Multibeam End-Fire Magnetoelectric Dipole Antenna Array for Millimeter-Wave Applications

A novel substrate integrated waveguide (SIW)-fed end-fire magnetoelectric (ME) dipole antenna is proposed. The antenna consisting of an open-ended SIW and a pair of electric dipoles has a simple structure that can be integrated into substrates conveniently. Both the open-ended SIW and the electric dipoles are effectively radiated together. Excellent performance, including a bandwidth of 44%, symmetrical radiation patterns that are almost identical in two orthogonal planes, low backward radiation, low cross polarizations, stable gain of around 5 dBi, and wide beamwidth of around 110°, are also obtained. An $8 \times 8$ SIW Butler matrix is then designed. Modifications to the geometry of the matrix provide more spacing to locate SIW phase shifters and phase compensation structures with wide bandwidth. By employing the proposed end-fire ME-dipole antenna array and the $8 \times 8$ Butler matrix, an eight-beam antenna array is realized. The fabricated prototype demonstrates that wide bandwidth, stable radiation patterns with cross polarizations of less than −28 dB and gain varying from 9 to 12 dBi can be obtained. The proposed multibeam end-fire ME-dipole antenna array would be an attractive candidate for millimeter-wave wireless applications due to its good performance, ease of integration, and low fabrication cost.

Compact Size, Equal-Length and Unequal-Width Substrate Integrated Waveguide Four Channel Phase Shifter

Objectives: In the past decade, Substrate Integrated Waveguide (SIW) phase shifters have attracted a lot of attentions, they are key components extensively deployed in phased array antennas, electronic scanning radars and other applications. In this paper a novel SIW four channel phase shifter is proposed. Methodology: It consists of five ports from which four ports act as output channels and the remaining is applied as a feed port. Also this substrate is integrated with a waveguide phase shifter designed to operate at 10 GHz. Phase channels are made by SIW with equal length and unequal width. The width of the phase channels differ from each other and can be controlled. The equations and the process of the whole design are preceeded by mathematical analysis. The propagation constant of the output signals and output phases in output channels have been adjusted by changing only the width of the output arms. Findings: As a result, a novel phase shifter is obtained. The experimental results of the prototype at 10GHz represents 22.5, 45, 67.5 degrees phase difference between one of the outputs in comparison to other outputs respectively. The measured bandwidth is 1.3 GHz bandwidth which has conformity with the simulation results. With the change of the position, the number of added vias and the width of output channels, a different phase shift can be obtained. The measurement of return loss and transmission coefficients are in good agreement with the simulation results in the proposed band. Application/Improvements: Therefore, such a SIW phase shifter is a good candidate for development of a compact size and integrated microwave systems.

An Integrable SIW Phase Shifter in a Partially Magnetized Ferrite LTCC Package

There is a growing need for small size integrable phased antenna arrays for emerging satellite communications on-the-move applications. Traditional ferrite-based phase shifters are generally bulky due to the need of electromagnets for biasing, yielding them unsuitable for this kind of application. In this paper, a novel compact light-weight substrate integrated waveguide (SIW) based phase shifter realized in a multi-layer ferrite low-temperature co-fired ceramic package with embedded bias windings is reported. By using embedded windings and operating the material in a partially magnetized state, the required bias magnetic field could be significantly reduced from typically about 1000 Oe to less than 50 Oe. Moreover, the presented phase shifter has two modes of operations corresponding to two different biasing scenarios of the SIW, namely, symmetric and anti-symmetric bias. Under anti-symmetric bias, the phase shifter can achieve high nonreciprocal phase shift, whereas under symmetric bias, the phase shift is reciprocal, but the available phase shift is less than the anti-symmetric case. The fabricated prototype operates in the 11.5–13.5-GHz range and has a peak figure of merit (phase shift per decibel of loss) of 102 $^{\circ}/{\hbox{dB}} $ and a maximum phase shift per unit length of 153 $^{\circ} /{\hbox{cm}}$ , which are more than five times the previously reported figures for this technology. Due to the use of embedded windings, the presented phase shifter offers a huge size reduction from the order of ${\hbox{cm}}^{3}$ to ${\hbox{mm}}^{3}$ , making it particularly useful for mobile phased-array applications.

A Digital SIW Phase Shifter Implemented by Switching Transverse Slots via PIN Diodes

AbstractA new idea of Substrate integrated waveguide (SIW) based digital phase shifter by controlling the transverse slots etched over the top metallic surface of SIW is proposed. A PIN diode is mounted on each transverse slot. Slots are made “enabled” or “disabled” by switching the state of PIN diode. A detailed explanation and demonstration is presented in this paper. As a result, a digital four bit phase shifter can be realized. Furthermore, equivalent circuit model for proposed device has also been discussed. Insertion loss is as low as 1.5 dB for a wide bandwidth of 31% (6.75–9.25 GHz), with a phase imbalance of ±4° and amplitude imbalance of ±0.5 dB. Simulation results agree well with the measured results.

Continuously tunable SIW phase shifter based on the buried varactors

A continuously tunable substrate integrated waveguide (SIW) phase shifter based on the buried varactors is proposed. A number of varactors buried within the substrate are introduced into the SIW section. Varactor diode is a nonlinear device, of which the capacitance varies with applied voltage of an exponent factor negative fractional value. The distribution of electric and magnetic fields can be changed with varied capacitance, which results in the phase-shifted. As one example, a phase shifter with four varactors is designed and implemented. Simulation and experimental results are in good agreements. The measured results show a return loss mostly better than 10 dB and an insertion loss less than 2.3 dB within a frequency range from 1.6 to 2.6 GHz (about 47.6% relative bandwidth). The maximum phase range is about 30° at the center frequency.

Dual-layered substrate-integrated waveguide six-port with wideband double-stub phase shifter

A dual-layered six-port front-end circuit on the basis of substrate-integrated waveguide (SIW) technology is presented and demonstrated. The use of SIW technology allows the development of a compact circuit with low radiation loss at millimetre-wave frequencies. The six-port architecture makes use of multilayer couplers that provide a wide coupling area through two slots; a new broadband SIW phase shifter composed of two H-plane stub lines and a reference line; and two SIW power dividers. The six-port design is free from loads as in the case of classic modified six-port architectures with eight ports. To validate the proposed concept, an integrated broadband six-port front-end circuit prototype was designed, fabricated and measured. Simulation and measurement results show that the proposed six-port circuit can easily operate at 60 GHz for V-band system applications. The two-layered structure presents interesting technological features including low profile, small volume and footprint and high-density integration.

Design of a Two-Element Antenna Array Using Substrate Integrated Waveguide Technique

The design of a two-element antenna array using the substrate integrated waveguide (SIW) technique and operating at 10 GHz is presented. The proposed antenna array consists of two SIW phase shifter sections with two SIW slot antennas. The phase shifting is achieved by changing the position of two inductive posts inserted inside each element of the array. Numerical simulations and experimental measurements have been carried out for three differential phases between the two antenna array elements, namely, 0°, 22.5°, and 67.5°. A prototype for each differential phase has been fabricated and measured. Results have shown a fairly good agreement between theory and experiments. In fact, a reflection coefficient of better than 20 dB has been achieved around 10 GHZ. The E-plane radiation pattern has shown a beam scan between 5° and 18° and demonstrated the feasibility of designing an SIW antenna phased array.

Broadband Substrate Integrated Waveguide 4$\,\times\,$4 Nolen Matrix Based on Coupler Delay Compensation

A broadband Nolen matrix in substrate integrated waveguide (SIW) technology is proposed and studied in this paper. Being feeding networks, Nolen matrices usually introduce significant phase dispersion in their standard form, thus limiting effective bandwidth. In this work, broadband frequency operation is achieved with adequate coupler delay compensation, resulting in a more parallel matrix topology. Consequently, H-plane couplers with continuous aperture are preferred in the proposed design as opposed to the cross-couplers previously used in the serial configuration. The SIW couplers and phase shifters of a balanced amplitude 4×4 Nolen matrix are designed at 77 GHz for radar applications. The resulting matrix that combines these elementary building blocks is fabricated and measured, and measured characteristics are in good agreement with theoretical and simulated predictions. This first design achieves excellent results over a 11.7% frequency bandwidth centered at 77 GHz. This modified Nolen matrix combines advantages of standard Nolen and Butler matrices and may be used as a building block for generalized orthogonal matrices.

Broadband Self-Compensating Phase Shifter Combining Delay Line and Equal-Length Unequal-Width Phaser

In this paper, a broadband self-compensating phase shifter is presented and developed on the basis of substrate integrated waveguide (SIW) technology. Since the SIW is a dispersive guided-wave structure, the effective bandwidth of SIW phase shifter is usually narrow. Phase shifts generated by two different structures, namely delay line and equal-length unequal-width phase shifter, are discovered in this work to present interesting opposite tendencies versus frequency. Therefore, an appropriate combination of them will make the phase shift almost constant over a very wide band. Design equations and process are given following a mathematical analysis. To demonstrate the interesting and useful features of the proposed technique, a 90° and a 45° self-compensating phase shifters are designed as showcases with standard printed circuit board process. For the 90° version, the measured amplitude and phase imbalance between the two paths are within 0.2 dB and 2.5° , respectively, within the frequency band from 25.11 to 39.75 GHz, or around 49% bandwidth. The return loss is found to be better than 12 dB within the frequency band of interest. The 45° one has the similar excellent performance. The measurements demonstrate that this type of SIW phase shifter is superior to all of its counterparts.

Design and implementation of a substrate integrated waveguide phase shifter

The design and implementation of a phase shifter based on the substrate integrated waveguide (SIW) technique operating at 10 GHz are presented. The proposed phase shifter consists of a SIW section with two inserted metallic posts. The phase shifting in this configuration is achieved by changing the diameter and the position of these posts. Numerical simulations have been carried out for different diameters and positions, which have shown good agreement with the theory. A parametric study was also conducted to assess the impact of errors made on the diameter and position of the two metallic posts. To prove the concept, prototypes were fabricated and measured. Experimental results agree well with simulations and S11 was better than –14 dB, S21 better than –1.08 dB and the phase error was less than 1.5°.