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MRF volume 4 issue 1 Cover and Front matter
High-range resolution multichannel DVB-T passive radar: aerial target detection
A method for improving range resolution in passive radar system is to jointly use more than one transmission channel of the same illuminator of opportunity (IO). This paper specifically focuses on the exploitation of multiple adjacent digital video broadcasting-terrestrial (DVB-T) channels for achieving high-range resolution profiles with a passive radar system operating in air surveillance scenar
Verification of ADS-B positioning by direction of arrival estimation
ADS-B provides convenient means of air traffic control (ATC) for its low cost and simple ground station hardware. In a low percentage of cases, aircraft positions transmitted via ADS-B are error prone due to e.g. faulty wiring with onboard navigation systems. In the proposed approach, direction of arrival (DOA) estimation is used to verify ADS-B airborne positions. The potential positioning error
Efficient location strategy for airport surveillance using Mode-S multilateration systems
In this paper, the use of regularization methods to solve the location problem in multilateration systems, using Mode-S signals, is studied, evaluated, and developed. The Tikhonov method has been implemented as a first application to solve the classical system of hyperbolic equations in multilateration systems. Some simulations are obtained and the results are compared with those obtained by the w
A multimodal sensor system for runway debris detection
For foreign object detection on runways, highly sensitive radar sensors give the opportunity to detect even very small objects, metallic and non-metallic, also under adverse weather conditions. As it is desirable for airport applications to install only small but robust installations along the traffic areas, millimeter-wave radars offer the advantage of small antenna apertures and miniaturized sys
Some OFDM waveforms for a fully polarimetric weather radar
Retrieval of cloud parameters in weather radar benefits from polarimetric measurements. Most polarimetric radars measure the full backscatter matrix (BSM) using a few alternating polarized sounding signals. Using specially encoded orthogonal frequency division multiplexing (OFDM) signals however, the BSM can be measured in a single simultaneous transmission of two orthogonally polarized signals. B
Enhancing sensitivity for emitter geolocation
Angle of arrival (AOA), time of arrival (TOA), and frequency of arrival (FOA) can be measured for a signal from multiple platforms. By combining such measurements it is possible to obtain high-accuracy emitter position estimates. This requires a data link with low latency and sufficient data-rate, and synchronization of the platforms in space, time, and search pattern. Typically several of the pla
Low-power 8-bit 5-GS/s digital-to-analog converter for multi-gigabit wireless transceivers
We present a method to realize a low-power and high-speed digital-to-analog converter (DAC) for system-on-chip applications. The new method is a combination of binary-weighted current cells and R-2R ladder and is specially suited for modern BiCMOS technologies. A prototype 5 GS/s DAC is implemented in 0.13 ?m SiGe BiCMOS technology. The DAC dissipates 26 mW and provides an SFDR higher than 48 dB f
Transient analysis of the EM field coupling to multi-conductor transmission lines using the NILT method
A simple and efficient numerical inversion Laplace transform (NILT) algorithm is implemented in MATLAB environment based on the quotient difference method to solve the problem of electromagnetic (EM) field coupling to lossy or lossless multi-conductor transmission lines (MTL) illuminated by an EM incident field. Two major points are treated in this work for the lossy MTL system excited by an incid
Active frequency-tripler MMICs for 300 GHz signal generation
Two frequency-tripler monolithic microwave integrated circuits (MMICs) reaching sub-millimeter-wave output frequencies of 315 GHz are presented. The convenient integration of transistor?based field effect transistor (FET) frequency multipliers into multifunctional MMICs is shown by integration of a single?stage frequency-tripler with a buffer amplifier generating ?0.5 dBm of peak output power at 2