FLASH images obtained with the antenna, Fig.2B shows images received with the two channels separately. D is a coronal FLASH image obtained with an elliptical 16-channel T/R microstrip array. Figure 1: Antenna (A) and the tuning/matching circuit (B) of one channel. Fig.1C shows the driving voltage (black) necessary to scale the B1+ field to a reference value when the antenna is placed at various...

In this paper, a novel dual-polarized microstrip array antenna is proposed and its characterisitics are investigated. general, antennas have complicated element excitation methods feeding circuits. Both-sided microwave-integrated circuit (MIC) technology such as magic-T can simplify the structure. As integrates magic-Ts, elements two orthogonal feed circuits be arrenged on single-layer substrat...

A shift register of N bit length can be conngured (for most N) with a single exclusive-OR gate to generate periodically 2 N ? 1 diierent states. As each state is directly related to the number of clock pulses received, such a circuit can be used as a counter. The sequential readout of the bit pattern requires nearly no additional logic and many 'shift counters' can easily be daisy chained durin...

Simple configuration and broadband characteristic are required for RF module in passive millimeter-wave imaging. We propose a layer-structured imaging module for simple structure, low profile and easy manufacturing [1]. This module is composed of lens antenna and detector module as shown in Fig.1. Lens and feeding horn antenna are designed to realize high-gain lens-antenna which operates over b...

This paper presents a new structure to implement compact narrowband high-rejection microstrip band-stop filter (BSF). This structure is the combination of two traditional BSFs: Spurline filter and BSF using defected ground structure (DGS). Due to inherently compact characteristics of both Spurline and interdigital capacitance (used as DGS), the proposed filter shows a better rejection performan...

1. Abstract: This paper describes a conformal Finite Difference Time Domain (FDTD) software package and presents its applications to RF antennas and mcrostrip circuit components. The program includes a Visual Basic GUI for graphically inputting the object geometries, setting source and boundary conditions, generating a non-uniform mesh, and post processing of the data. A robust Conformal Finite...

The relative permittivity of LCP material has been characterized within the whole 60 GHz frequency band using the microstrip ring resonator (MRR) method. Using a circuit model, the gap capacitance of the MRR has been taken into account in order to improve the accuracy of the determined relative permittivity. The results show that the relative permittivity of LCP is almost constant (εr ≈ 3.1) wi...

A microstrip structure with a narrow return plane generates large common-mode radiation. The guard trace attached near the signal line can reduce common-mode radiation. In general, the guard trace needs a lot of via connections to the return plane for keeping the guard trace grounded. The guard trace with long intervals of vias causes resonance and additional radiation. We propose a novel techn...

This paper aims to analyse the design techniques of differential transmission lines loaded with metamaterials. Specifically, complementary split-ring resonators (CSRRs) were etched on the ground plane of a microstrip transmission line in order to mitigate both differentialand common-mode propagation in differential signalling. Several prototypes were manufactured and characterised in printed ci...

The propagation factor of the Niobium-based distributed Superconductor-Insulator-Superconductor (SIS) tunnel junction has been studied by modelling at frequencies 70200 GHz. In the modelling, the distributed SIS junction was simulated as a microstrip distributed component. Furthermore, in the studies, the reactive part of the SIS tunnel junction quantum admittance was included in the model circ...