Reliability study of a tunable Ka-band SIW-phase shifter based on liquid crystal in LTCC-technology

2014 ◽  
Vol 7 (5) ◽  
pp. 521-527 ◽  
Author(s):  
Sebastian Strunck ◽  
Alexander Gaebler ◽  
Onur H. Karabey ◽  
Andreas Heunisch ◽  
Baerbel Schulz ◽  
...  
Keyword(s):  
Liquid Crystal ◽  
Phase Shifter ◽  
Effective Permittivity ◽  
Phase Shifters ◽  
Phased Array Antenna ◽  
Differential Phase Shift ◽  
Differential Phase ◽  
Phase Errors ◽  
Antenna Module ◽  
High Level

A tunable substrate-integrated waveguide phase shifter using low-temperature co-fired ceramic (LTCC)-technology is presented in this paper. By changing the effective permittivity in the liquid crystal (LC)-filled waveguide, the differential phase can be tuned continuously. This is achieved by means of an analog signal applied to the electrodes, surrounding the LC. The design allows for precise tuning of the differential phase, which is proven with a Monte Carlo measurement resulting in phase errors of less than 3° at 28 GHz. Besides that, the ambient temperature dependency of the module is shown. The phase shifter has a high integration level and can be included into a complete and lightweight single-phased array antenna module. The phase shifter is realized with a high level of integration which is available through the multilayer process of the LTCC. It has a length of 50 and provides a differential phase shift of more than 360° at 28 GHz. The figure of merit for tunable phase shifters is >40°/dB.

scholarly journals Microwave Liquid Crystal Enabling Technology for Electronically Steerable Antennas in SATCOM and 5G Millimeter-Wave Systems

Crystals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 514 ◽  
Author(s):  
Rolf Jakoby ◽  
Alexander Gaebler ◽  
Christian Weickhmann
Keyword(s):  
Liquid Crystal ◽  
Phase Shift ◽  
Millimeter Wave ◽  
Phase Shifter ◽  
Beam Steering ◽  
Phase Shifters ◽  
Worst Case ◽  
Differential Phase Shift ◽  
Digital Architecture ◽  
Differential Phase

Future satellite platforms and 5G millimeter wave systems require Electronically Steerable Antennas (ESAs), which can be enabled by Microwave Liquid Crystal (MLC) technology. This paper reviews some fundamentals and the progress of microwave LCs concerning its performance metric, and it also reviews the MLC technology to deploy phase shifters in different topologies, starting from well-known toward innovative concepts with the newest results. Two of these phase shifter topologies are dedicated for implementation in array antennas: (1) wideband, high-performance metallic waveguide phase shifters to plug into a waveguide horn array for a relay satellite in geostationary orbit to track low Earth orbit satellites with maximum phase change rates of 5.1°/s to 45.4°/s, depending on the applied voltages, and (2) low-profile planar delay-line phase shifter stacks with very thin integrated MLC varactors for fast tuning, which are assembled into a multi-stack, flat-panel, beam-steering phased array, being able to scan the beam from −60° to +60° in about 10 ms. The loaded-line phase shifters have an insertion loss of about 3 dB at 30 GHz for a 400° differential phase shift and a figure-of-merit (FoM) > 120°/dB over a bandwidth of about 2.5 GHz. The critical switch-off response time to change the orientation of the microwave LCs from parallel to perpendicular with respect to the RF field (worst case), which corresponds to the time for 90 to 10% decay in the differential phase shift, is in the range of 30 ms for a LC layer height of about 4 µm. These MLC phase shifter stacks are fabricated in a standard Liquid Crystal Display (LCD) process for manufacturing low-cost large-scale ESAs, featuring single- and multiple-beam steering with very low power consumption, high linearity, and high power-handling capability. With a modular concept and hybrid analog/digital architecture, these smart antennas are flexible in size to meet the specific requirements for operating in satellite ground and user terminals, but also in 5G mm-wave systems.

scholarly journals Potential of Liquid-Crystal Materials for Millimeter-Wave Application

2018 ◽  
Vol 8 (12) ◽  
pp. 2544 ◽  
Author(s):  
Toshiaki Nose ◽  
Ryota Ito ◽  
Michinori Honma
Keyword(s):  
Liquid Crystal ◽  
Millimeter Wave ◽  
Microstrip Line ◽  
Phase Shifter ◽  
Substrate Surface ◽  
Antenna System ◽  
Phase Shifters ◽  
Phased Array Antenna ◽  
Electric Circuits ◽  
Line Type

In this study, we reviewed three topics regarding the application of liquid-crystal (LC) materials to millimeter-wave (MMW) devices. It is essential to develop useful measurement methods for refractive indices of LC materials in the MMW region. Herein, a novel measurement method using optical short is demonstrated using a Si semiconductor substrate. There are two approaches to develop MMW LC devices. One is the quasi-optical approach, which involves scaling up the optical components, and the other approach involves integrating the LC materials into high-frequency electric circuits. A three-dimensional (3D) printer is used to fabricate the Fresnel lens, which is a typical quasi-optical device useful in the MMW region, where we can develop the tunable lens by introducing LC materials. A planar-type MMW waveguide is advantageous for integrating the LC materials to develop LC MMW devices using the second approach. We investigated a useful microstrip-line-type LC phase shifter by developing a novel conversion circuit to introduce the LC material onto the dielectric substrate surface. A phase shifter is an important MMW component that is used to attain a phased array antenna system, and a minimal twin antenna array is demonstrated using the microstrip-line-type LC phase shifters.

scholarly journals Temperature Characterization of Liquid Crystal Dielectric Image Line Phase Shifter for Millimeter-Wave Applications

Crystals ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 63
Author(s):  
Henning Tesmer ◽  
Rani Razzouk ◽  
Ersin Polat ◽  
Dongwei Wang ◽  
Rolf Jakoby ◽  
...  
Keyword(s):  
Liquid Crystal ◽  
Millimeter Wave ◽  
Insertion Loss ◽  
Phase Shifter ◽  
Ground Plane ◽  
Temperature Dependent ◽  
Differential Phase ◽  
Dependent Behavior ◽  
The Impact ◽  
Temperature Dependent Behavior

In this paper we investigate the temperature dependent behavior of a liquid crystal (LC) loaded tunable dielectric image guide (DIG) phase shifter at millimeter-wave frequencies from 80 GHz to 110 GHz for future high data rate communications. The adhesive, necessary for precise fabrication, is analyzed before temperature dependent behavior of the component is shown, using the nematic LC-mixture GT7-29001. The temperature characterization is conducted by changing the temperature of the LC DIG’s ground plane between −10∘C and 80 ∘C. The orientation of the LC molecules, and therefore the effective macroscopic relative permittivity of the DIG, is changed by inserting the temperature setup in a fixture with rotatable magnets. Temperature independent matching can be observed, while the insertion loss gradually increases with temperature for both highest and lowest permittivity of the LC. At 80 ∘C the insertion loss is up to 1.3dB higher and at −10∘C it is 0.6dB lower than the insertion loss present at 20 ∘C. In addition, the achievable differential phase is reduced with increasing temperature. The impact of molecule alignment to this reduction is shown for the phase shifter and an estimated 85% of the anisotropy is still usable with an LC DIG phase shifter when increasing the temperature from 20 ∘C to 80 ∘C. Higher reduction of differential phase is present at higher frequencies as the electrical length of the phase shifter increases. A maximum difference in differential phase of 72∘ is present at 110 GHz, when increasing the temperature from 20 ∘C to 80 ∘C. Nevertheless, a well predictable, quasi-linear behavior can be observed at the covered temperature range, highlighting the potential of LC-based dielectric components at millimeter wave frequencies.

Phased-array antennas using novel PSoC-controlled phase shifters for wireless applications

2021 ◽  
pp. 1-13
Author(s):  
Aparna B. Barbadekar ◽  
Pradeep M. Patil
Keyword(s):  
Insertion Loss ◽  
Phase Shifter ◽  
Phased Array ◽  
Phase Shifters ◽  
Control Circuit ◽  
Power Divider ◽  
Phased Array Antenna ◽  
Phased Array Antennas ◽  
Array Antennas ◽  
Low Insertion Loss

Abstract The paper proposes a system consisting of novel programmable system on chip (PSoC)-controlled phase shifters which in turn guides the beam of an antenna array attached to it. Four antennae forming an array receive individual inputs from the programmable phase shifters (IC 2484). The input to the PSoC-based phase shifter is provided from an optimized 1:4 Wilkinson power divider. The antenna consists of an inverted L-shaped dipole on the front and two mirrored inverted L-shaped dipoles mounted on a rectangular conductive structure on the back which resonates in the ISM/Wi-Fi band (2.40–2.48 GHz). The power divider is designed to provide the feed to the phase shifter using a beamforming network while ensuring good isolation among the ports. The power divider has measured S11, S21, S31, S41, and S51 to be −14, −6.25, −6.31, −6.28, and −6.31 dB, respectively at a frequency of 2.45 GHz. The ingenious controller is designed in-house using a PSoC microcontroller to regulate the control voltage of individual phase shifter IC and generate progressive phase shifts. To validate the calibration of the in-house designed control circuit, the phased array is simulated using $s_p^2$ touchstone file of IC 2484. This designed control circuit exhibits low insertion loss close to −8.5 dB, voltage standing wave ratio of 1.58:1, and reflection coefficient (S11) is −14.36 dB at 2.45 GHz. Low insertion loss variations confirm that the phased-array antenna gives equal amplitude and phase. The beamforming radiation patterns for different scan angles (30, 60, and 90°) for experimental and simulated phased-array antenna are matched accurately showing the accuracy of the control circuit designed. The average experimental and simulated gain is 13.03 and 13.48 dBi respectively. The in-house designed controller overcomes the primary limitations associated with the present electromechanical phased array such as cost weight, size, power consumption, and complexity in design which limits the use of a phased array to military applications only. The current study with novel design and enhanced performance makes the system worthy of the practical use of phased-array antennas for common society at large.

scholarly journals Analysis and Optimization of Thin-Film Ferroelectric Phase Shifters

1999 ◽  
Vol 603 ◽  
Author(s):  
R. R. Romanofsky ◽  
F. W. Van Keuls ◽  
J. D. Warner ◽  
C. H. Mueller ◽  
S. A. Alterovitz ◽  
...  
Keyword(s):  
Insertion Loss ◽  
Room Temperature ◽  
Phase Shifter ◽  
Ferroelectric Phase ◽  
Phase Shifters ◽  
Phased Array Antenna ◽  
New Type ◽  
Novel Devices ◽  
K Band

AbstractMicrowave phase shifters have been fabricated from (YBa2Cu3 O7-δ or Au)/SrTiO3 and Au/BaxSr1−xTiO3 films on LaAlO3 and MgO substrates. These coupled microstrip devices rival the performance of their semiconductor counterparts at Ku- and K-band frequencies. Typical insertion loss for room temperature ferroelectric phase shifters at K-band is ≈5 dB. An experimental and theoretical investigation of these novel devices explains the role of the ferroelectric film in overall device performance. A roadmap to the development of a 3 dB insertion loss phase shifter that would enable a new type of phased array antenna is discussed.

scholarly journals Design of 3-Bit Digital RF Phase Shifter for Wireless Communication

2019 ◽  
Vol 8 (2) ◽  
pp. 2292-2296
Keyword(s):  
Phase Shift ◽  
Wireless Communication ◽  
Transmission Line ◽  
Phase Shifter ◽  
Phased Array ◽  
Low Cost ◽  
Phase Shifters ◽  
Phased Array Antenna ◽  
Radio System ◽  
Digital Phase

In this paper, a 3-bit digital phase shifter based on switched transmission line technique using coplanar waveguide is proposed. The design has the resonant frequency of 10 GHz which can be used in wireless communication applictaions. Recent developments in radio frequency components development has raised as a significant way for constructing low loss phase shifters. MEMS phase shifters whose insertion loss is low and high isolation uses minimum power. This helps to bring low cost and light weighted phased array antennas. The transmission line length and wavelength decides the characteristics of phase shift. The phase shifter design consists of coplanar waveguides having center conductor width of 100µm and the gap of 14 µm on a FR-4 epoxy substrate with thickness of 1.6mm. The design is simulated using ADS to yield phase shift of 45, 90 and 180. The benefits of digital phase shifters include achieving flat phase over a wide bandwidth as well as having higher power handling and linearity with uniform performance. The phase shifters are used in different fields which includes microwave devices, feeder of radio system, phased array antenna, coherent radio system, etc.

scholarly journals Acoustic Wave Reflection Control Based on Broadband Differential Phase Shifters

2021 ◽  
Vol 7 ◽  
Author(s):  
Zifu Qin ◽  
Xiaohan Liu ◽  
Chu Ma
Keyword(s):  
Phase Shift ◽  
Acoustic Waves ◽  
Phase Shifter ◽  
Wave Reflection ◽  
Phase Shifters ◽  
Complex Phase ◽  
Reflected Waves ◽  
Differential Phase ◽  
Location Patterns ◽  
Working Frequency

Controlling the flow of acoustic waves has broad applications in acoustic imaging, communication, energy harvesting, audio systems, etc. Metasurfaces have been developed for wave control. In this work we propose the design of broadband differential phase shifters for acoustic reflected waves, which can achieve nearly constant phase shift values over a broad frequency ranges. We further demonstrate the design of a broadband differential π phase shifter that works in the frequency range of (10 kHz, 16 KHz) and its applications in acoustic metasurfaces for steering and focusing of reflected acoustic waves. The metasurfaces we designed have the following advantages: 1) The metasurface is formed with binary patterns instead of more complex phase discretization steps, thus the metasurface realization is less complex for fabrication and assembly. 2) The phase shift values of the two basic phase shifter elements are broadband, thus we do not need to fabricate new elements for each frequency. Rearranging the same elements into different location patterns would allow us to tune the working frequency of the metasurfaces.

Microwave Phase Shifters Using Ferroelectric (Ba,Sr)TiO3 Films

2002 ◽  
Vol 720 ◽  
Author(s):  
Won-Jeong Kim ◽  
Eun-Kyoung Kim ◽  
Seung-Eon Moon ◽  
Seok-Kil Han ◽  
Su-Jae Lee ◽  
...  
Keyword(s):  
Phase Angle ◽  
Phase Shifter ◽  
Metal Layer ◽  
Bias Field ◽  
Phase Shifters ◽  
Metal Loss ◽  
Differential Phase ◽  
Bst Films ◽  
Dc Bias ◽  
Dc Bias Field

AbstractThe ferroelectric (Ba0.6Sr0.4)TiO3 (BST) films were prepared on (001) MgO single crystals by pulsed laser deposition. Coplanar waveguide (CPW) type phase shifters controlled by external dc bias field were fabricated on BST films using a 2 μm thick metal layer to reduce metal loss. Microwave properties of the CPW phase shifter were measured using a HP 8510C vector network analyzer from 0.1 – 20 GHz. The fabricated CPW phase shifters (8 mm long) exhibited differential phase angle of 100 ° at 10 GHz with a dc bias field of less than 80 kV/cm between center and ground conductors. Furthermore, a stable differential phase angle (102 ± 3.5 o) was observed from another CPW while changing the power of incident microwave from -10 to +30 dBm. Gap size dependent dielectric constant of the BST film was observed and a simple correction method was suggested in the paper. These results demonstrate the possible application of ferroelectric tunable devices on a high power tunable wireless telecommunication.

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