Electrically Tunable Phase Shifters With Air-Dielectric Sandwich Structure

AbstractElectrically tunable microwave phase shifter was developed by inserting dielectric slab and piezoelectric actuator inside a waveguide. Air-dielectric sandwich structure of dielectric material and thin air gap was placed inside a waveguide, where the thickness of air gap is controlled by the actuator. Small changes in the ratio between the thickness of dielectric material and air gap induce significant changes in the effective dielectric constant of the air-dielectric sandwich structure. Phase shifts of 20∼200 degrees were realized with the dielectric materials such as (Mg, Ca)TiO3 while the thickness of air gap is changed between 0 to 30 μm by piezoelectric control. Since the dielectric ceramics has very small loss (tand ∼ 10-4) and the air gap has practically no loss, the total structure shows low insertion loss.

Download Full-text

Mathematical model to predict the characteristics of polarization in dielectric materials: The concept of piezoelectrcity and electrostriction

10.31221/osf.io/39572 ◽

2019 ◽

Author(s):

Chem Int

Keyword(s):

Mathematical Model ◽

Electric Field ◽

Lead Zirconate Titanate ◽

Dielectric Material ◽

Strain Curve ◽

Dielectric Materials ◽

Lead Zirconate ◽

Simulation Software ◽

Constitutive Law ◽

Basic Material

Model was developed for the prediction of polarization characteristics in a dielectric material exhibiting piezoelectricity and electrostriction based on mathematical equations and MATLAB computer simulation software. The model was developed based on equations of polarization and piezoelectric constitutive law and the functional coefficient of Lead Zirconate Titanate (PZT) crystal material used was 2.3×10-6 m (thickness), the model further allows the input of basic material and calculation of parameters of applied voltage levels, applied stress, pressure, dielectric material properties and so on, to generate the polarization curve, strain curve and the expected deformation change in the material length charts. The mathematical model revealed that an application of 5 volts across the terminals of a 2.3×10-6 m thick dielectric material (PZT) predicted a 1.95×10-9 m change in length of the material, which indicates piezoelectric properties. Both polarization and electric field curve as well as strain and voltage curve were also generated and the result revealed a linear proportionality of the compared parameters, indicating a resultant increase in the electric field yields higher polarization of the dielectric materials atmosphere.

Download Full-text

Analysis of Optimum Precoding schemes in Millimeter Wave System

Recent Advances in Computer Science and Communications ◽

10.2174/2666255813666200102124758 ◽

2020 ◽

Vol 13 ◽

Author(s):

Divya Singh ◽

Aasheesh Shukla

Keyword(s):

Power Consumption ◽

Millimeter Wave ◽

Spectral Efficiency ◽

Phase Shifter ◽

Phase Shifters ◽

Achievable Rate ◽

Wave System ◽

Digital To Analog Converter ◽

Hybrid Precoding ◽

Analog Converter

Background : Millimeter wave technology is the emerging technology in wireless communication due to increased demand for data traffic and its numerous advantages however it suffers from severe attenuation. To mitigate this attenuation, phased antenna arrays are used for unidirectional power distribution. An initial access is needed to make a connection between the base station and users in millimeter wave system. The high complexity and cost can be mitigated by the use of hybrid precoding schemes. Hybrid precoding techniques are developed to reduce the complexity, power consumption and cost by using phase shifters in place of converters. The use of phase shifters also increases the spectral efficiency. Objective: Analysis of Optimum Precoding schemes in Millimeter Wave System. Method: In this paper, the suitability of existing hybrid precoding solutions are explored on the basis of the different algorithms and the architecture to increase the average achievable rate. Previous work done in hybrid precoding is also compared on the basis of the resolution of the phase shifter and digital to analog converter. Results: A comparison of the previous work is done on the basis of different parameters like the resolution of phase shifters, digital to analog converter, amount of power consumption and spectral efficiency. Table 2 shows the average achievable rate of different algorithms at SNR= 0 dB and 5 dB. Table 3 also compares the performance achieved by the hybrid precoder in the fully connected structure with two existing approaches, dynamic subarray structure with and without switch and sub connected or partially connected structure. Table 4 gives the comparative analysis of hybrid precoding with the different resolutions of the phase shifter and DAC. Conclusion: In this paper, some available literature is reviewed and summarized about hybrid precoding in millimeter wave communication. Current solutions of hybrid precoding are also reviewed and compared in terms of their efficiency, power consumption, and effectiveness. The limitations of the existing hybrid precoding algorithms are the selection of group and resolution of phase shifters. The mm wave massive MIMO is only feasible due to hybrid precoding.

Download Full-text

Microwave phase shifter based on fibre Bragg grating

Electronics Letters ◽

10.1049/el:19981703 ◽

1998 ◽

Vol 34 (21) ◽

pp. 2051 ◽

Cited By ~ 3

Author(s):

B. Ortega ◽

J.L. Cruz ◽

M.V. Andrés ◽

A. Díez ◽

D. Pastor ◽

...

Keyword(s):

Phase Shifter ◽

Bragg Grating ◽

Fibre Bragg Grating ◽

Microwave Phase Shifter

Download Full-text

Memristors as Candidates for Replacing Digital Potentiometers in Electric Circuits

Electronics ◽

10.3390/electronics10020181 ◽

2021 ◽

Vol 10 (2) ◽

pp. 181

Author(s):

Ivo Marković ◽

Milka Potrebić ◽

Dejan Tošić

Keyword(s):

Phase Shifter ◽

Voltage Divider ◽

Frequency Characteristics ◽

Phase Shifters ◽

Pass Filter ◽

Electric Circuits ◽

Digital Potentiometer ◽

Memristive Circuits ◽

Parasitic Effects ◽

Additional Level

Digital potentiometers are substantial components for the design of many mixed-signal electronic circuits and systems. Their capability to program resistance value almost instantly provides hardware designers an additional level of freedom. Unfortunately, this feature is limited to DC and lower frequencies, due to parasitic effects. Nowadays, memristors as continuously tunable resistors are becoming candidates for potentiometer successors. Memristors are two-terminal non-volatile devices which have less significant parasitic effects and a wide resistance range. The memristance value can be changed on the fly. Using nanotechnology, memristor implementation has a nanoscale footprint with nanosecond transition between resistive states. In this paper, we present a comparison between the frequency characteristics of digital potentiometers and the only commercially available memristors. Memristor parasitic effects dominate at higher frequencies which extends the bandwidth. In order to present the advantages of memristive circuits, we have analyzed and implemented tunable circuits such as a voltage divider, an inverting amplifier, a high-pass filter, and a phase shifter. A commercially available memristor by KnowM Inc. is used for this purpose. Experimental results obtained by the measurements verify that a memristor has equal or better characteristics than a digital potentiometer. Memristive realizations of voltage dividers and inverting amplifiers have a wider bandwidth, while filters and phase shifters with a memristor have almost identical frequency characteristics as the corresponding realizations with a digital potentiometer.

Download Full-text

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

International Journal of Microwave and Wireless Technologies ◽

10.1017/s1759078721001094 ◽

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.

Download Full-text

Electrically tunable microwave phase shifter based on layered ferrite-ferroelectric structure

Electronics Letters ◽

10.1049/el:20010746 ◽

2001 ◽

Vol 37 (19) ◽

pp. 1154 ◽

Cited By ~ 9

Author(s):

V. Demidov ◽

P. Edenhofer ◽

B. Kalinikos

Keyword(s):

Phase Shifter ◽

Tunable Microwave ◽

Microwave Phase Shifter ◽

Ferroelectric Structure

Download Full-text

Waveguide dielectric phase shifter with fast piezoelectric control

IEEE MTT-S International Microwave Symposium Digest, 2005. ◽

10.1109/mwsym.2005.1516853 ◽

2006 ◽

Cited By ~ 2

Author(s):

V. Kazmirenko ◽

Y. Poplavko ◽

M. Jeong ◽

S. Baik

Keyword(s):

Phase Shifter ◽

Dielectric Phase ◽

Piezoelectric Control

Download Full-text

A Simple Microstrip Phase Shifter

Australian Journal of Physics ◽

10.1071/ph920105 ◽

1992 ◽

Vol 45 (1) ◽

pp. 105 ◽

Cited By ~ 4

Author(s):

SW Amy ◽

MI Large

Keyword(s):

Low Power ◽

Phase Shifter ◽

Narrow Band ◽

Phase Shifters ◽

Performance Data ◽

Frequency Range ◽

Design Chart ◽

Binary Phase ◽

Gain Variation ◽

And Performance

A novel, inexpensive, series-connected loaded-line (SCOLL) phase shifter has been developed for the Molonglo Observatory Synthesis Telescope. The phase shifter, which operates at 0�843 GHz, consists of a ",3>'/8 length of microstrip with series connected varactors at each end. Although designed as a binary phase shifter, the insertion phase varies almost linearly with varactor reactance, with very little gain variation for phase ranges up to 90�. Thus, driven by a digital-to-analogue (D/ A) converter, a SCOLL becomes a programmable phase shifter of any desired resolution. The same technique would be suitable for narrow-band low power applications in the frequency range 0�1 to 10 GHz. This paper gives the basic theory of SCOLL phase shifters, a design chart, construction details and performance data.

Download Full-text