International Journal

This paper presents a novel assessment method that minimizes test-fixture-induced errors in non-coaxial power combiner measurement by extending the port reduction method. This method involves terminating certain ports to acquire the scattering matrix of an -port network from the scattering matrix measured at a reduced port order. The entire DUT scattering matrix is obtained from multiple scanning

Spatial telemetry links on nanosatellites require more and more reconfigurable beam antennas to improve the Earth coverage. The bi-mode Agile Radiating Matrix Antenna (8.0?8.4 GHz) was successfully designed to solve such kind of problems by using an isoflux mode associated with a switchable directive one. However, such an antenna introduces some manufacturing problems , mainly due to the small ava

We investigate the frequency diverse array (FDA) for joint radar and communication systems. The basic idea is to use the transmitter/receiver modules of the radar system for communication purpose during listening mode as a secondary function. The radar will be performing its routine functions during the active mode as a primary function. An FDA at the transmitter side will be used to produce an or

In this paper, a completely reconfigurable comb-line bandpass filter is presented. Due to the modularity, different standard coupling matrix topologies like the folded form, cascaded triplets, and the cul-de-sac form can be implemented and tested. Circuit-based coupling matrices like the extracted pole topology can easily be realized as well. Different types of input-/output- and cross-couplings c

The surface impedance characteristics of a wire grid composed of infinitely long parallel conducting wires embedded in lossless and lossy frequency-dispersive chiral background media have been investigated. Using wavefield decomposition approach for a chiral background and with the application of impedance boundary conditions for a wire grid, an analytic expression for the surface impedance of a w

This paper presents the design and analysis of a miniaturized, coplanar waveguide-fed ultra-wideband monopole on-chip antenna with band-notch characteristics. By incorporating a ?U?-shaped slot in the feedline, a band-notch is realized in the frequency range of 7.9?8.4 GHz to avoid interference from the X-band uplink satellite communication system. The proposed antenna achieved good voltage standi

This paper investigates the generation of passive intermodulation (PIM) in coaxial connectors during vibration. A series of experiments were designed and the simulation model and method were proposed for understanding these phenomena. We found that PIM is mainly influenced by the contact stress and contact surface roughness during vibration. Thus, a power spectral density method is presented to id

In this article, we propose three-dimensional antenna systems for determining the position of electromagnetic radiation source at an unknown location. Received signal power at different antennas and position of radiation source are used as training data for Artificial Neural Network (ANN). It is found that, a well-trained ANN is computationally efficient and capable of predicting the unknown locat

A new design method of an ultra-wideband circularly-polarized planar multiple-input-multiple-output (MIMO) antenna is presented in this paper. The proposed MIMO antenna consists of four unit cell antennas, being comprised of a microstrip feed line and a square slotted ground plane. In the proposed unit cell design, a circular stub is protruded from the ground plane strip for achieving circular pol