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This work presents the design of a dual band frequency modulated continuous wave (FMCW) radar receiver (RX) at the 2.4 and 5.8 GHz industrial, scientific and medical (ISM) bands. The designed low noise amplifier (LNA) has a single ended 50 Ω input stage followed by an active balanced-to-unbalanced (balun) stage. The radio frequency (RF) signal is then down-converted to a low intermediate frequency...
An analytical model is presented to calculate phase noise spectrum and jitter of a radar system driven by a phase-locked loop (PLL). The high-pass filtered phase noise of the voltage-controlled oscillator (VCO) is modelled as an Ornstein-Uhlenbeck process. For a triangular FMCW frequency sweep, a non-stationary process is used to calculate the PLL output phase. A condition for the loop filter capacitance...
This paper presents a method of enhancing the aperture size and the effective number of elements of a millimeter wave radar array to make it competitive and complementary as an imaging system for collision avoidance and imaging in adverse environments. We increase aperture size by using a Vernier geometry, with a MIMO overlay to provide adaptive beamforming and multi-target tracking. We reduce the...
Ultra-Wideband (UWB) technology completes available technologies of fast data links on short distances and brings new possibilities, e. g. clear identification and possibility to locate each active element in space precisely. Usual applications include various types of precise positioning systems or radiolocation display systems, however, transferring images in very high definition is also expected...
In this study, combination of three-dimensional ray tracing and electron density estimator IRI (International Reference Ionosphere) is used to obtain the ionosonde output, ionogram. The developed structure is able to generate both vertical ionograms where the receiver and transmitter are in the same location and oblique ionograms where the transmitter and receiver are in the different locations. The...
In an increasingly dense and complex environment identification of the radars by Radar Warning Receivers (RWR) has utmost importance. In this study the process of obtaining the meaningful pulse sequences from radars with jitter and agile Pulse Repetition Interval (PRI) types is investigated. The effectiveness of the deinterleaving algorithm can be measured by one of the critical elements, which is...
In this paper, FGPA implementations of amplitude and phase comparison direction finding methods are presented. In amplitude comparison direction finding (AC-DF), the power ratio between the receiver channels is compared with the values in the look-up-table that is generated using antenna patterns. In phase comprison direction finding (FC-DF), basically the phase difference is extracted between channels...
Pulse deinterleaving is the process of identifying which received pulses belong to which emitter sources. Pulse deinterleaving techniques generally consist of multi-parameter algorithms that utilize pulse parameters such as angle of arrival, frequency, pulse width and pulse amplitude and interval-only algorithms. In conventional multi-parameter deinterleaving pulse width and pulse amplitude parameters...
This paper presents the design of a Phase Locked Loop (PLL) system and frequency synthesizer for an architecture that aims to miniaturize a digital radar test bed implemented using discrete microwave components. The designed PLL architecture acts as a frequency synthesizer to provide three distinct frequencies of 800 MHz, 2.0 GHz, and 2.4 GHz to the respective chips of the digital radar system. Full...
RADAR, an acronym for Radio Detection and Ranging, is used for various purposes both military as well as civilians. A fire-control radar (FCR) is specifically designed radar to provide information (mainly target azimuth, elevation and range) to a fire control system in order to calculate a firing solution (i.e. information on how to direct weapons such that they hit the target(s)). This Paper mainly...
We present a composite suite of technologies for spectral coexistence of existing communication and radar systems using the Xampling framework. For a stand-alone communication system, we consider a cognitive radio (CRo) that receives multiband signals with unknown carrier frequencies and directions of arrival, and demonstrate joint spectrum sensing via CompreSsed CArrier and Direction-ofarrival Estimation...
This contribution is based on an novel imaging system able to create real time radar images for personnel security screening recently presented. The imaging is performed as the person being screened continuously moves across a corridor populated with transmitters and receivers, and taking advantage of the person's movement to increase the number of observation angles. As part of a preliminary study...
We demonstrate a compact design for enhancing the 3dB beamwidth of a 60 GHz single-chip millimeter-wave frequency modulated continuous wave (FMCW) radar with integrated on-chip antennas. We use thin (Xfreespace/5) dielectric periodic lenses on top of the epoxy cover of the single-chip radar to change the effective material properties of the epoxy, which changes the field distribution and hence the...
In this paper, we discuss some conditions for LPI signals, and propose a system with multiple users requiring these LPI properties using the optimal families of polyphase sequences recently discovered by Park et. al. We discuss and prove the bound on the key space for candidates, and conclude that our system is more secure than those employing encrypted sequences using AES-128 against brute-force...
Range imaging (RIM), which uses multiple frequencies, enables wind profiler radars (WPRs) to measure wind and turbulence with enhanced range resolution. Adaptive clutter suppression, which controls sidelobes by using subarrays, is useful for mitigating clutter contamination. In order to apply RIM and adaptive clutter suppression not only to scientific researches but also to operational monitoring...
Ultra-wideband RF systems offer a multitude of advantages over narrow band systems. One major point is that these systems can perform multiple functions, like communications, radar and others all using the same aperture. This big advantage of these systems is at the same time their biggest handicap: The wideband receivers are open to much more types of signals compared to narrow band systems. Due...
Today's electronic warfare (EW) systems require fast electronic intelligence (ELINT) to measure frequency parameters of radars and to scan predefined frequency bands for possible target radar emissions. Target radar signals are usually strictly time limited events and ELINT systems should be able to catch these emissions and categorize the source radar according to its threat library in a very short...
Radars are known for target detection but with time it found applications in other areas as well. In this paper, we demonstrate a method to send data over radar signal for communication without interfering with the original purpose of target detection. The proposed radar system is implemented using software defined radio (SDR).
This paper introduce design, implementation and measurement of front end crystal video receiver (CVR) that operates in the frequency range of 8–10 GHZ to intercept short duration pulse radar signals. The proposed receiver is designed with two outputs, video signal for real-time signal processing and an amplified version of the received signal for frequency measuring and/or determine the presence of...
This article describes the outdoor mapping method of robot group using omnidirectional radio link communication. The issues of designing the radar system based on wearable radio communication devices with adding new functionality without changing the hardware are discussed. The method for providing the energetically concealed location of network objects detection is suggested. The calculations show...
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