This paper describes a monolithic-microwave integrated-circuit (MMIC) active phase shifter using a variable resonant circuit with a large amount of variable phase. We first propose a novel active phase-shifter configuration that uses a variable resonant circuit with second-order all-pass network characteristics. Phase can be changed with a constant amplitude by varying the capacitance or the inductance of the resonant circuit. Next, an experimental MMIC active phase shifter with input active matching is presented. A phase shift of over 100/spl deg/ and an insertion loss of 4/spl plusmn/1 dB are obtained from 2.2 to 2.8 GHz. The chip size is less than 1.0 mm/sup 2/. Finally, an experimental 360/spl deg/ MMIC active phase shifter is presented. Over the bandwidth of 40 MHz at 2.44 GHz, the insertion gain is 2.0/spl plusmn/0.7 dB and the phase error is within /spl plusmn/4/spl deg/ when measured in 30/spl deg/ steps.

An MMIC active phase shifter using a variable resonant circuit [and MESFETs]

X-Band high power, low loss and fast switching twin-toroid type ferrite phase shifter is designed and fabricated. Differential phase shift (DPS), insertion loss, high power characteristics and impedance matching are determined and optimized using finite element solver in CST Microwave Studio. The effect of high order modes propagating in the structure is examined and methods to suppress these modes are investigated. 15dB return loss is obtained for all phase states and operating temperature range in 12% bandwidth at X-Band. Switching time smaller than 10us is achieved using a digitally controlled high current driver circuit.

X-Band high power ferrite phase shifter

This paper presents a novel 3D integration approach for a low-cost 3-bit true time delay (TTD) phase shifter for 11.5 - 13GHz communication phased-array antenna. The module is realized with surface-mountable PIN diodes and introduces signal delay from 1 to 7λ at the center frequency of the work-band, which represent delay from 80 to 560 ps with increment 80 ps. The proposed phase shifter implements on-board TTL compatible digital drivers. The solution is based on a MCM approach, realized using standard MCM-D, MCM-L or PCB technology. The substrate material is either 98% alumina ceramic (Al203), or Rogers TMM10i, both materials having similar RF properties, allowing to transfer the design between the different technologies without further fine-tuning of the layout. The high-frequency board-to-board transitions utilize BGA technology, making the module compatible with the existing SMT assembly process. The module occupied aria is 50x25mm.

MCM low-cost true time delay phase shifter

Future communication systems at W-band are demanding highly directive antenna systems with beam-steering capability For the hardware implementation of analogue beam-steering at millimetre waves, the microwave liquid crystal (LC) technology is ideally suited It takes advantage of specifically synthesised LCs for microwaves in combination with appropriate device and biasing concepts, where the orientation of the LC, and therefore, its effective permittivity can be continuously tuned It has low dielectric losses above 10GHz with a decreasing trend with increasing frequency To exploit these unique characteristics, the focus of this scientific work is set for the first time on the investigation of an LC-based network with mixed discrete beam-switching and continuous beam-steering capability between the switching states for high-gain antennas at W-band It consists of a Butler matrix combined with continuously tuneable phase shifters and a novel type of RF switch, an interference-based Single-Pole n-Throw (SPnT) The interference principle of the SPnT allows a continuously adjustable power splitting ratio, and hence, the
generation of multiple beams

Different technologies are investigated for the realisation of this mixed network Due to its high level of integrability and compact designs, the standard low temperature co-fired ceramic technology is examined, however, for a first proof-of-concept at Ka-band only For W-band, two low-loss technologies are investigated: tuneable metallic and dielectric waveguides While metallic waveguides are well suited for the realisation of low-loss non-tuneable feeding networks, dielectric waveguides are better suited for the realisation of tuneable LC components at (sub)millimetre waves, since no metallic boundaries are limiting the integration of an electrical biasing network As non-tuneable core part, a Butler matrix with an average insertion loss of 35 dB at 102 GHz is realised, which is based on a novel multifunctional crossover design, allowing a miniaturised in-plane realisation of the overall mixed network As key component for tuning of the mixed beam-switching and beam-steering network, a step-index dielectric waveguide phase shifter is presented With a phase
shifter figure-of-merit of 100 °/dB at 102 GHz, this fully electrically biased phase shifter is going far beyond the state-of-the-art for electrically tuneableW-band phase shifter

To stay on the same technology platform and to allow an in-plane realisation from the input port up to the radiating elements, the interference-based SPnTs are additionally investigated by a hybrid implementation of metallic and dielectric waveguides It exhibits an insertion loss of 3dB, while providing an isolation of 27 dB Hence, this hybrid metallic and dielectric waveguide technology reveals a
high potential not only for the presented LC-based mixed beam-switching and beam-steering network, but also for LC-tuned continuous beam-steering networks at frequencies above 100 GHz, since low-loss metallic waveguide feeding networks can be generally combined with high-performance tuneable dielectric waveguides

Liquid Crystal Mixed Beam-Switching and Beam-Steering Network in Hybrid Metallic and Dielectric Waveguide Technology

Over the last few years, artificial materials (metamaterials) demonstrating so-called left-handed behaviour have been reported [1,2]. Left-handed materials have a peculiar property in that their group velocity is negative with respect to their phase velocity. During the course of an investigation into a new rectangular waveguide phase shifter, it was discovered that the ferrite also supports left-handed propagation, albeit over a very limited range of frequencies. Left-handedness thus also appears to be possible in natural materials, not just in artificial ones. In this paper, the salient features of the ferrite medium inside the phase shifter are presented, and the longitudinal component of the Poynting vector is examined throughout the guide's cross-section at multiple frequencies.

Left-handed behaviour in a ferrite-filled, antisymmetrically-biased rectangular waveguide phase shifter

Microwave and millimeter wave phase shifters-volume I-dielectric and ferrite phase shifters, by Shiban K. Koul and Bharathi Bhat, Artech House, Boston. 1991, 388 pages. Price: U.S. $88.00 or Europe £66.00. ISBN 0-89006-31 9-2

Microwave and millimeter wave phase shifters. Volume II: Semiconductor and delay line phase shifters, by Shiban K. Koul and Bharathi Bhat, Artech House, Boston, 1991. xxi + 276 pages. Price: U.S. $88.00 or Europe £66.00. ISBN 089006-585-3

Adalbert Beyer

Papers

Microwave and millimeter wave phase shifters-volume I-dielectric and ferrite phase shifters, by Shiban K. Koul and Bharathi Bhat, Artech House, Boston. 1991, 388 pages. Price: U.S. $88.00 or Europe £66.00. ISBN 0-89006-31 9-2

Microwave and millimeter wave phase shifters. Volume II: Semiconductor and delay line phase shifters, by Shiban K. Koul and Bharathi Bhat, Artech House, Boston, 1991. xxi + 276 pages. Price: U.S. $88.00 or Europe £66.00. ISBN 089006-585-3