CiteULike: dcastro's phase-shifter

Active Integrated Circulating Antenna based on Non-Reciprocal Active Phase Shifters

A Ohlsson — 2008-05-08T06:51:24-00:00

Antennas and Propagation, 2007. EuCAP 2007. The Second European Conference on (2007), pp. 1-5.

An active circulator is presented in this paper to be integrated with a patch antenna. This antenna tries to overcome the non reciprocity behaviour of active antenna in a compact way.

Improved wide-band Schiffman phase shifter

Yong-Xin Guo — 2008-04-16T19:16:31-00:00

Microwave Theory and Techniques, IEEE Transactions on, Vol. 54, No. 3. (2006), pp. 1196-1200.

In this paper, one improved wide-band Schiffman phase shifter is presented by modifying the ground plane underneath the coupled lines. In this new design, with the ground plane under the coupled lines removed, the even-mode impedance will be increased substantially. Meanwhile, we propose that one additional isolated rectangular conductor is placed under the coupled lines to act as one capacitor so that the odd-mode impedance is decreased. The proposed new design was simulated by the full-wave electromagnetic software IE3D and validated by the measurement. Compared with the cascading microstrip multisection coupled-line configuration, our newly proposed planar one with a patterned ground plane is small in size and, meanwhile, has a good performance. As an example, one Schiffman phase shifter on a double-sided printed circuit board is designed, simulated, fabricated, and measured. The measured amplitude and phase imbalance between the two paths are within 0.5 dB and 5/spl deg/, respectively, over the frequency band from 1.5 to 3.1 GHz, or around 70% bandwidth. The measured return loss is found to be better than -12 dB over the operating frequency band.

Composite right/left-handed transmission line metamaterial phase shifters (MPS) in MMIC technology

J Perruisseau-Carrier — 2007-11-07T07:50:58-00:00

Microwave Theory and Techniques, IEEE Transactions on, Vol. 54, No. 4. (2006), pp. 1582-1589.

This paper presents the modeling and design of one-dimensional metamaterial phase shifters (MPSs) in monolithic-microwave integrated-circuit technology based on the composite right/left-handed transmission-line approach. From a theoretical point-of-view, we show that existing design expressions are restricted to phase shifters behaving as effective media, which is the case only if sufficiently large L and C loading elements can be designed in the given technology and at the frequency of interest. Therefore, we propose new design expressions, which are exact on the basis of the circuit model of a unit cell in the structure. We show that the new expressions must be used to design integrated MPSs and the theory is verified by means of measurements of one- and two-cell phase shifters exhibiting a 0/spl deg/ phase shift at 17.5GHz. The designed one-cell phase shifter provides a -10-dB input return-loss bandwidth larger than 10% with phase shifts of +29/spl deg/ and -30/spl deg/ at 16.5 and 18.5 GHz, respectively. The insertion loss is -1.3 dB at the center frequency and -1.7 dB at the limit of the bandwidth.

A new broadband differential phase shifter fabricated using a novel CRLH structure

Yong-Zhuo Zou — 2007-11-07T07:47:38-00:00

Journal of Zhejiang University - Science A, Vol. 8, No. 10. (29 October 2007), pp. 1568-1572.

Abstract Broadband phase shifters are mostly proposed and fabricated based on the scheme proposed by Shiffman, which uses a coupled line with far ends connected together and a uniform transmission line to give a differential phase shift. Based on the unique dispersion property of the composite right/left-handed (CRLH) metamaterial structure, a new configuration is presented in this paper for fabricating the broadband differential phase shifter, which employs a novel CRLH metamaterial structure as one of the differential phase-shift arms, instead of the conventional coupled line. The new circuit can achieve a phase shift of 90� in an operational bandwidth as broad as one octave and its phase deviations are quite small. An original design of the novel broadband phase shifter is presented, in which the artificial CRLH structure was implemented by microstrip quasi-lumped elements. Both the simulated and measured results of the 90� broadband differential phase shifter are presented.

Compact linear lead/lag metamaterial phase shifters for broadband applications

MA Antoniades — 2007-10-23T07:56:07-00:00

Antennas and Wireless Propagation Letters, Vol. 2 (2003), pp. 103-106.

A compact one-dimensional phase shifter is proposed using alternating sections of negative refractive index (NRI) metamaterials and printed transmission lines (TL). The NRI metamaterial sections consist of lumped element capacitors and inductors, arranged in a dual TL (high-pass) configuration. By adjusting the NRI-medium lumped element values, the phase shift can be tailored to a given specification. Periodic analysis is applied to the structure and design equations are presented for the determination of the lumped element parameters for any arbitrary phase shift. To validate the design, various phase shifters are simulated and tested in coplanar waveguide (CPW) technology. It is demonstrated that small variations in the NRI-medium lumped element values can produce positive, negative or 0/spl deg/ phase shifts while maintaining the same short overall length. Thus, the new phase shifter offers some significant advantages over conventional delay lines: it is more compact in size, it exhibits a linear phase response around the design frequency, it can incur a phase lead or lag which is independent of the length of the structure and it exhibits shorter group delays.