Monolithic Phase Shifter Research Articles

A monolithic distributed phase shifter based on right-handed nonlinear transmission lines at 30 GHz

The epitaxial material, device structure, and corresponding equivalent large signal circuit model of GaAs planar Schottky varactor diode are successfully developed to design and fabricate a monolithic phase shifter, which is based on right-handed nonlinear transmission lines and consists of a coplanar waveguide transmission line and periodically distributed GaAs planar Schottky varactor diode. The distributed-Schottky transmission-line-type phase shifter at a bias voltage greater than 1.5 V presents a continuous 0°–360° differential phase shift over a frequency range from 0 to 33 GHz. It is demonstrated that the minimum insertion loss is about 0.5 dB and that the return loss is less than −10 dB over the frequency band of 0–33 GHz at a reverse bias voltage less than 4.5 V. These excellent characteristics, such as broad differential phase shift, low insertion loss, and return loss, indicate that the proposed phase shifter can entirely be integrated into a phased array radar circuit.

A Distributed Phase Shifter Using Bi1.5Zn1.0Nb1.5O7/Ba0.5Sr0.5TiO3 Thin Films

We report the demonstration of a monolithic phase shifter employing Bi1.5Zn1.0Nb1.5O7 (BZN)/Ba0.5Sr0.5TiO3 (BST) thin films on sapphire substrates. The BST and BZN thin films are successively deposited by radio-frequency magnetron sputtering. A distributed phase shifter with a coplanar-waveguide transmission line periodically loaded with the BZN/BST capacitors is fabricated. The return loss of the circuit is better than −13 dB from 1 to 12 GHz, and it provides 65° phase shift with an insertion loss of −4 dB at 12 GHz. The results show that BZN/BST thin films are promising candidate dielectrics for rf/microwave tunable applications.

Phase shifts and wave-packet displacements in neutron interferometry and a nondispersive, nondefocusing phase shifter

A phase shifter in neutron interferometry creates not only a phase shift but also a spatial displacement of the neutron wave packet, leading to a reduced interference contrast. This wave-packet displacement constitutes a major hindrance in measuring large phase shifts. Here we present a nondispersive configuration with two identical phase shifters placed on one path in successive gaps of a symmetric triple Laue (LLL) interferometer. As compared to a single phase shifter, the dual phase shifter generates double the phase shift, yet a net null displacement of the wave packet. The interferometer thus remains fully focused however large the phase shift or the incident wavelength spread, permitting a white incident neutron beam as in the case of a purely topological phase measurement. Misalignment angles of a monolithic nondispersive dual phase shifter are equal and opposite in the two gaps. Its phase therefore remains nondispersive over a much wider angular range and attains a minimum magnitude at the correct orientation, obviating the need to alternate the phase shifter between the two interferometer paths during its alignment. The setup is hence ideally suited for measuring neutron coherent scattering lengths to ultrahigh precision.

Ultrashort laser pulse splitting upon resonant reflection on a mirror-based waveguide grating

A resonant waveguide grating based on a high reflectivity mirror causes a 2pi phaseshift of adjustable slope in the spectrum of an ultrashort light pulse, giving rise to a controllable, lossless temporal pulse splitting. This monolithic phase shifter can simply be placed on the path of the beam as a mirror. A functional element was designed and fabricated. Temporal splitting of a femtosecond laser pulse is experimentally demonstrated. The possibility of obtaining variable delay between subpulses is theoretically discussed.

A phase shifter on a slot line loaded with varactors designed on the basis on nanodimensional films of barium-strontium titanate

A monolithic phase shifter is designed on the basis of a slot transmission line periodically loaded with ferroelectric varactors. The varactors are designed on the basis of nanodimensional films of Ba0.8Sr0.2TiO3. It is found that, in the frequency band from 12.0 to 13.5 GHz, the figure of merit of the phase shifter is more than double that in the case when the thickness of the nanodimensional ferroelectric film used for the varactors is decreased from 36 to 18 nm.

Microwave monolithic phase shifter for optical transmission at 40 Gb/s

AbstractThis paper deals with a design technique for an integrated planar phase shifter on GaAs substrate at millimetre‐wave frequencies for optical transmission applications at 40 Gb/s. We numerically show how an amplifier can be adequately associated with a nonconstant magnitude phase shifter to avoid a magnitude modulation of the optical signal when tuning the phase shift. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 254–258, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11345

A Ku-Band 5-Bit Phase Shifter Using Compensation Resistors for Reducing the Insertion Loss Variation

This paper describes the performance of a Ku-band 5-bit monolithic phase shifter with metal semiconductor field effect transistor (MESFET) switches and the implementation of a ceramic packaged phase shifter for phase array antennas. Using compensation resistors reduced the insertion loss variation of the phase shifter. Measurement of the 5-bit phase shifter with a monolithic microwave integrated circuit demonstrated a phase error of less than 7.5° root-mean-square (RMS) and an insertion loss variation of less than 0.9 dB RMS for 13 to 15 GHz. For all 32 states of the developed 5-bit phase shifter, the insertion losses were 8.2 ± 1.4 dB, the input return losses were higher than 7.7 dB, and the output return losses were higher than 6.8 dB for 13 to 15 GHz. The chip size of the 5-bit monolithic phase shifter with a digital circuit for controlling all five bits was 2.35 mm × 1.65 mm. The packaged phase shifter demonstrated a phase error of less than 11.3° RMS, measured insertion losses of 12.2 ± 2.2 dB, and an insertion loss variation of 1.0 dB RMS for 13 to 15 GHz. For all 32 states, the input return losses were higher than 5.0 dB and the output return losses were higher than 6.2 dB for 13 to 15 GHz. The size of the packaged phase shifter was 7.20 mm × 6.20 mm.

Design and performance of a Ka-band monolithic phase shifter utilizing nonresonant FET switches

This paper describes design consideration and performance of a Ka-band monolithic phase shifter utilizing nonresonant FET switches. The switches show broad-band on/off characteristics up to 60 GHz without using inductors; thus, robust circuit design is possible for a switched-line phase shifter. To determine circuit topology, we introduce a schematic design approach. As a result, desired phase shift as well as good matching characteristics can be realized. The developed 4-bit monolithic phase shifter demonstrates an overall phase deviation less than 5/spl deg/ rms and an insertion loss variation less than 0.65 dB rms from 33 to 35 GHz. For all 16 states, the insertion loss is measured to be 13.1/spl plusmn/1.1 dB and the VSWR is less than 1.6. The chip size of the monolithic phase shifter is 2.5 mm/spl times/2.2 mm.

X-band RF MEMS phase shifters for phased array applications

In this work, development of a low-loss radio frequency (RF) microelectromechanical (MEMS) 4-bit X-band monolithic phase shifter is presented. These microstrip circuits are fabricated on 0.021-in-thick high-resistivity silicon and are based on a reflection topology using 3-dB Lange couplers. The average insertion loss of the circuit is 1.4 dB with the return loss >11 dB at 8 GHz. To the best of our knowledge, this is a lowest reported loss for X-band phase shifter and promises to greatly reduce the cost of designing and building phase arrays.

Novel monolithic phase shifter combining ferroelectrics and high temperature superconductors

Abstract We describe a monolithic phase shifter which combines the low loss of high temperature superconductivity (HTS) with the variable dielectric properties of a ferroelectric material SrTiO3. Phase shifts greater than 28 degrees per wavelength were observed around 30 K. Benefits of the combination of HTS and ferroelectric materials are described. The compatibility of YBa2Cu3O7-x and other ferroelectric materials is discussed.

Novel monolithic phase shifter combining ferroelectrics and high temperature superconductors

AbstractWe describe a monolithic phase shifter which combines the low loss of high‐temperature superconductivity (HTS) with the variable dielectric properties of a ferroelectric material SrTiO3. Phase shifts greater than 28 degrees per wavelength were observed around 30° K. The compatibility of YBa2Cu3O7‐x and other ferroelectric materials is discussed. © 1992 John Wiley & Sons, Inc.

Control of a GaAs monolithic Ka-band phase shifter using a high-speed optical interconnect

The use of a high-speed optical interconnect in the control of a Ka-band GaAs monolithic phase shifter is described. A 16-b serial control signal was used to modulate the output of a laser transmitter, and the transmitted optical signal was detected and demultiplexed into 16 parallel electrical outputs using a high-speed hybrid GaAs optoelectronic integrated circuit. Four of the parallel output lines were interfaced to the 4-b phase shifter, and high-speed, optically controlled switching of the phase shifter was observed at clock frequencies to 30 MHz using an interferometric technique.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Cryogenic Operation of a Monolithic Slow-Wave Variable Phase Shifter (Short Paper)

A GaAs slow-wave variable phase shifter has been investigated at 4.2, 77, and 300 K ambient temperatures over the 2-18-GHz frequency range. Differential phase shift Delta Theta has been measured and presented as a set of curves parameterized in terms of temperature covering the entire frequency range. Analytical explanations are provided for the phase shift Theta and insertion loss L behavior as functions of temperature, frequency, and bias voltage. The Schottky microstrip line resistivity ratio at 77 K is found to vary between 4 and 6 over the frequency range studied, giving about a 5:1 reduction in resistivity (or a 2:1 reduction in L) by going to liquid nitrogen temperature.

A Novel MMIC X-Band Phase Shifter

A novel configuration for monolithic phase shifters is presented. The layout and fabrication of a single chip, four-bit X-band phase shifter, measuring 3.7 x 2.3 mm, is described in some detail. The first samples to be assessed exhibited full 360° coverage at the design frequency, operation throughout X-band, good matches, and an insertion loss less than 5 dB.

C-band 6-bit GaAs monolithic phase shifter

Design, fabrication, and performance of a 6-bit GaAs monolithic phase shifter for use in the 5-6-GHz frequency range are described. The chip includes an analog control bit (0-11°) for phase correction in a closed-loop configuration and five digitally controlled phase bits. A ± 1° phase variation was achieved for the 11.25°, 22.5°, and 45° bits while for the 90° and 180° bits the phase variation was ±6° over 5 to 6 GHz. The return loss was better than 15 dB and insertion-loss flatness was within ± 1 dB over this frequency band. The phase error over a temperature range of 25-80°C and the 5-6-GHz frequency band was less than ± 0.5°, ± 1°, ± 1°, ± 2°, and ± 2° for the 11.25°, 22.5°, 45°, 90°, and 180° bits, respectively, with a maximum of .8-dB insertion-loss variation.

C-Band 6-Bit GaAs Monolithic Phase Shifter

Design, fabrication, and performance of a 6-bit GaAs monolithic phase shifter for use in the 5-6-GHz frequency range are described. The chip includes an analog control bit (0-11° ) for phase correction in a closed-loop configuration and five digitally controlled phase bits. A +- 1° phase variation was achieved for the 11.25°, 22.5°, and 45° bits while for the 90° and 180° bits the phase variation was +- 6° over 5 to 6 GHz. The return loss was better than 15 dB and insertion-loss flatness was within +- 1 dB over this frequency band. The phase error over a temperature range of 25-80°C and the 5-6-GHz frequency band was less than +- 0.5°, +- 1°, +- 1°, +- 2°, and +- 2° for the 11.25°, 22.5°, 45°, 90°, and 180° bits, respectively, with a maximum of .8-dB insertion-loss variation.

A novel MMIC X-band phase shifter

A novel configuration for monolithic phase shifters is presented. The layout and fabrication of a single chip, four-bit <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">X</tex> -band phase shifter, measuring 3.7 × 2.3 mm, is described in some detail. The first samples to be assessed exhibited full 360 ° coverage at the design frequency, operation throughout X-band, good matches, and an insertion loss less than 5 dB.

Wide-Band Monolithic Phase Shifter

A wide-band monolithic phase shifter operating in the 2-8 GHz frequency range is described. Six GaAs FET's per bit are used as switch elements in a bridge configuration which alternatively becomes a high-pass or a low-pass section. Their low-impedance state is modeled as a resistor, the high-impedance state as a combination of capacitors and resistors. In the design approach, the high-impedance state equivalent shunt capacitor is not resonated. Instead, these capacitors become part of the resulting high-pass, low-pass sections. In this way, the maximum theoretical bandwidth that a high-pass, low-pass section can provide is achieved despite the nonideal switching elements.

Wide-band monolithic phase shifter

A wide-band monolithic phase shifter operating in the 2-8- GHz frequency range is described. Six GaAs FET's per bit are used as switch elements in a bridge configuration which alternatively becomes a high-pass or a low-pass section. Their low-impedance state is modeled as a resistor, the high-impedance state as a combination of capacitors and resistors. In the design approach, the high-impedance state equivalent shunt capacitor is not resonated. Instead, these capacitors become part of the resulting high-pass, low-pass sections. In this way, the maximum theoretical bandwidth that a high-pass, low-pass section can provide is achieved despite the nonideal switching elements.

A Monolithic Single-Chip X-Band Four-Bit Phase Shifter

X-band GaAs monolithic passive phase shifter with 22.5°, 45°, 90°, and 180° phase bits are developed using FET switches. By cascading all four bits, a four-bit digital phase shifter with 5.1+-0.6-dB insertion loss is realized on a single 6.4 x 7.9 x 0.1-mm chip.