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This paper details the design and implementation of a modulator-less beam steering transmitter based on a revised DDS-PLL phase shifter architecture. The proposed topology targets low data rate communications for Internet-of-Things systems, and has been demonstrated using an FPGA evaluation board and a custom PCB with four PLLs centered at 2.453-GHz. Measured system performance for an experimental 32-kbps data rate achieved through a 16-PSK modulation scheme are discussed. The proposed architecture is frequency independent, can be used in multi-band devices and has the potential for being integrated as an RF System-on-Chip. [ABSTRACT FROM AUTHOR]

Copyright of La Radiologia Medica is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of La Radiologia Medica is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article describes a lumped component model which accounts for coupling between inductors in GaAs MMIC design. The model was developed using a full-wave approach. The validity of the proposed circuit has been successfully tested. Experimental results are reported to validate the model. [ABSTRACT FROM AUTHOR]

A simplified model is suggested for describing aperture-coupled patch antennas in CAD applications. The scattering parameters of the antenna are calculated by assuming a single mode distribution for the currents on the slot and on the microstrip-line. The coupling between the slot and the patch is represented by superimposing a contribution from a fundamental mode and that from higher order modes. The former is described by a complex eigenvalue of a cavity model with impedance walls. The latter is described by a parallel plate waveguide model, which properly accounts for the storage of reactive energy close to the slot. Numerical results are presented and compared with experiments. In particular, S-band patches have been fabricated and tested to demonstrate the accuracy of the model. [ABSTRACT FROM AUTHOR]

A novel input buffer for very high speed and high resolution track-and-hold amplifiers has been developed in BiCMOS technology. The configuration retains the benefits of a cascode configuration in terms of distortion and adaptability to various advanced switched-emitter (source)-follower based architectures while maintaining supply requirements similar to a conventional degenerated common emitter amplifier. To demonstrate the advantages of the presented architecture a distortion analysis has been carried out. The closed form formulas show very good agreement with Spectre® simulations using complete models. [ABSTRACT FROM AUTHOR]

Anderson–Fabry disease is an X-linked lysosomal storage disorder resulting from a deficiency of the enzyme a-galactosidase A (a-Gal A) and subsequent cellular storage of the enzyme’s substrate globotriaosylceramide (Gb3) and related glycosphingolipids. We report a case of Anderson–Fabry disease with cardiac involvement evaluated with cardiovascular MRI. Disease progression was observed despite enzyme replacement therapy. [ABSTRACT FROM AUTHOR]

A novel phase shifter topology for digital phased antenna arrays based on a low-power phase control block joint with an innovative PLL design is presented. Experimental results obtained by a prototype are reported validating the architecture capabilities. [ABSTRACT FROM AUTHOR]

The paper introduces an MMIC 90° hybrid based on MIM capacitors and active inductors. The component has been used to implement an integrated variable attenuator operating at 5.8 GHz. Simulations and experimental results are reported to describe the design process and validate the proposed configuration. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 325–327, 2003 [ABSTRACT FROM AUTHOR]

A monolithic 20 GHz 90° hybrid is introduced. The hybrid design is based on a lumped-component approach that makes use of planar coupled inductors. The hybrid model and design technique are discussed. Experiments validating the structure are reported. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 29: 392–394, 2001. [ABSTRACT FROM AUTHOR]

A new topology for phase-shift control in the transmitter module of phased array antennas is introduced. The proposed structure is based on a hybrid DDS-PLL approach. An offset-PLL evolution is proposed in order to preserve phase resolution, along with a maximum phase shift of 360°. Experimental results obtained by a prototype are reported, validating the architecture potentialities. [ABSTRACT FROM AUTHOR]

A new distributed voltage controlled oscillator (DVCO) is presented. The proposed topology allows a very wide tuning range VCO and fine–coarse tuning. The design of a prototype DVCO is discussed and measurements are reported showing improved performance in terms of phase noise, tuning range and power consumption. [ABSTRACT FROM AUTHOR]