Abstract
We propose the use of inverse scattering for the design of filters, in microstrip technology, with a specified reflective group delay response. The inverse scattering is performed using the layer peeling algorithm. The method is simple and easily implemented numerically . To validate the method, filters with a reflective linear group delay were designed and implemented. The simulation and measurement results are shown to agree well the target response. ©2010 IEEE.

Abstract
A method based on the theory of inverse scattering, more specifically the layer-peeling method, is used for the design of planar microwave electromagnetic bandgap filters in microstrip technology. The method was originally used for the design of fiber Bragg gratings. To validate the method, a 4-pole Chebyshev filter was designed and constructed. The measured results are shown to agree well with the specifications.

Abstract
This paper presents the design of a low-pass microwave filter based on the EBG (Electromagnetic Bandgap) concept. The structure is composed of a microstrip line in one of the layers and two different periodic superimposed EBG structures in the ground plane. The first structure defines the characteristics of the filter in the pass-band whereas the second periodic structure is used to reduce the second harmonic spurious response. The filter exhibits a flat pass-band response and a cut-off rate better than 380 dB/octave. © 2007 IEEE.

Abstract
This paper presents a printed two C-shaped monopoles antennas array for dual-band WLAN application. The two antenna elements are closely spaced at a distance of only 0.09 2.4GHz. High isolation between these two radiation elements is achieved by using the neutralization technique, which has been demonstrated as an effective way to increase the isolation for single band PIFA antennas [1, 2]. In this work, the neutralization technique has been implemented to the printed monopole antenna design. We demonstrate that by introducing two RF switches, we can not only design a compact monopole antenna array with high isolation for single band operation but also can extend this method to design a compact dual band antenna array. The proposed antenna array contains two C-shaped monopoles with a shorting line, on which two RF switches were integrated, connecting two arms of the antenna elements. Experiment results indicate that the proposed antenna array has a 10dB bandwidth that covers the required frequencies for dual-band WLAN applications (2.4/5.2GHz) with isolation higher than 15dB over both operation bands. The proposed antenna has been designed and optimized using Ansoft HFSS. © 2011 IEEE.

Abstract
This study aims to design a compact two antennas array on a USB dongle for WLAN 5.8 GHz application (IEEE 802.11n). The proposed antenna adopts an Inverted-L antenna (ILA) structure, which can be easily integrated into an industry product. The two antenna elements are closely spaced and the high isolation between them is achieved by using the neutralization technique. Moreover, the impedance matching of both antennas is improved by introducing one vertical stub on the neutralizing line. In this way, both the isolation between the two antennas and the impedance matching of each antenna can be improved simultaneously. The experimental results show that this antenna has wide operation bandwidth (S11 <-10 dB) from 5.7 to more than 6 GHz with isolation always better than 10 dB. © 2012 IEEE.

Abstract
The Daphne project has been addressing the adoption of an optical fiber infrastructure for future aircrafts. Beyond the obvious motivation of reduced weight and electromagnetic interference, the availability of a huge amount of bandwidth makes the optical fiber well suited to transport Radio Frequency (RF) signals transparently, while avoiding cumbersome dedicated RF cabling. An integrated optical network may be exploited to transport radio signals from diverse aircraft antennas ranging from satellite/earth communications, collision avoidance, GPS signals for positioning and attitude determination, weather/detection RADAR to corrosion sensors. Such network can also support passenger infotainment and mobile communication services, such as cellular GSM/UMTS/LTE, broadband Wi-Fi (IEEE 802.11) and Ultra-Wide-Band Wimedia/WiGig. Specifically, the optical fiber infrastructure may provide connectivity from external antennas (through remote nodes) to RF transceivers installed in the cockpit and avionics bay (head-end nodes); in the context of the present paper, the transmission of differential GPS signals used to provide aircraft attitude information will be discussed. The use of GPS for aircraft attitude determination has been under discussion for more than 20 years [1]. It consists in performing carrier-phase differential processing of measurements from GPS antennas affixed to the frame of the aircraft, which yields centimeter- or millimeter-level accuracies, provided that integer phase ambiguities are resolved [2]. The attitude algorithm consists in a highly accurate real time kinematic (RTK) technique, given the short baseline distance between antennas, in which the main antenna acts as a Base station and two auxiliary antennas as Rovers. In the present experiment, we used a setup consisting of two-antennas (Base and Rover), which is enough to evaluate the RTK performance. A particular aspect of concern stems from the fact that the transmission of optical signals through a complex optical fiber network is subject to the occurrence of reflections in the multitude of connectors spanning the path between a remote node and a head-end node. Therefore, we will focus our analysis on the performance impact of optical reflections affecting the power level stability of the optical source. © 2012 IEEE.