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Real-time reconfigurable digital heterodyne LFMCW radar systems offer degrees of flexibility in selecting parameters for the transmitted waveform and for the digital receiver signal processing chain. These parameters are tightly-coupled and a change in any of them will affect the rest, and subsequently the entire system. We listed these parameters and performed an analysis to aid radar system designers to optimally select suitable permutations of them depending on their reconfigurability and system requirements. Deramping of a real-sampled up-going LFMCW signal was used as a basis of this study. This paper presents a brief abstract of the analysis results, with examples of the effects of different parameter permutations. We found that this analysis has enabled us to assess FPGA signal processing blocks' reconfiguration parameters, and to identify radar system boundaries/limitations. These findings will be applied to future reconfigurable radar receiver research at TuDelft.

A signal may not be detected and identified due to the presence of serious noise. Coherent integration is an important approach for focusing the energy of the signal in pulse-Doppler radar. For moving targets, the problem of migration through range cells (MTRC) will degrade the coherent integration result. This paper presents a new coherent integration method for multi-channel radar system to focus near field moving targets. The envelope correction coupled with backprojection in spatial and fast-time domain is performed, followed with coherent integration in slow-time domain. The simulated results demonstrate the effectiveness of the method in target detection.

The design and development of a personnel radar detection system based on the identification of micro-Doppler shifts from heartbeat motion is presented here. The paper reviews the phenomenon of micro-Doppler effects measured in radar systems, and describes a specific detection scheme based on this theory. The detection performance for a general radar system is described, and specific results for a prototype system are then presented and analyzed in support of the theory. The signal processing techniques used to estimate heartbeat rates are described in detail and experimental results are provided for actual human targets demonstrating the effectiveness of the system design. The results focus on the detection capability as a function of standoff range to provide a real-world performance measure of the system.

This paper describes a 94-GHz ground-based CW-LFM radar system for cloud monitoring. This system transmits 1 W and the bandwidth is configurable up to 2000 MHz. A two-antenna configuration is used to improve the Tx-Rx isolation and two different antennas are used to avoid parallax errors. An RF characterization of the radar architecture is presented. Lastly, a drone detection experiment and preliminary cloud measurements are carried out to validate the radar operation.

In this paper, we propose a novel waveform design approach for coherent multiple-input multiple-output (MIMO) radar to make radar radiation management and transmit-receive beam refocusing at the radar receiver feasible. The transmitted waveforms are coded in the space domain to form a defocused transmit beam pattern for radiation management, and further in time domain to be orthogonal so that they can be separated and extracted through matched filtering at the radar receiver for transmit-receive beam refocusing processing. The proposed waveform design and beamforming approaches are validated through simulations.

This paper presents a fully-integrated D-Band bistatic frequency-modulated continuous-wave radar (FMCW) radar sensor based on a 130nm SiGe BiCMOS technology for short-range applications. The radar sensor includes transmit and receive antennas integrated in an embedded-wafer-level-ball-grid-array (eWLB) package. The transceiver chip is based on ×30 frequency multiplication, which enables the use of off-the-shelf 4GHz phase-locked-loops. A fully-differential IQ receiver is implemented by means of a differential 3-dB branch line coupler. On-wafer measurements show a maximum output power of 0 dBm. The radar sensor is mounted on a low cost PCB and is used in conjunction with an FPGA based baseband board for analog-to-digital conversion, processing and evaluation of the IF signals. In order to verify the operation, FMCW measurements of static targets are performed with a sweep bandwidth of up to 10 GHz, which corresponds to a minimum range-resolution of 3 cm. The radar chip consumes around 560mW from a 3.3V power supply and the package size is 12mm × 6 mm.

This paper describes a novel technique for radar imaging of space objects. The approach is founded on using a small satellite near the target of interest as the receive end of a high-power ground-based radar transmitter for imaging. The small satellite is equipped with an open loop receiver for sampling and processing the observed wideband signal and a GPS receiver for orbit determination. It also contains appropriate algorithms for signal processing and receive and transmit antennas for collecting the radar signal and transmitting telemetry to the ground. The discussion in this paper is limited mainly to a point design for simplicity. It should be noted that the reach and capability of the proposed approach go beyond the example presented in this paper.

Frequency Diverse Array (FDA) concepts, first introduced in 2006, present a novel approach to electronic beam steering. FDA differs from other conventional arrays in that it applies a small frequency increment to the center frequency for each individual array element creating range, angle, time and frequency offset dependent beam pattern. A conceptual framework is studied for target acquisition and tracking in AFD radar systems.

In this paper we investigate the potentiality to exploit a passive forward scatter radar (PFSR) based on WiFi transmissions for vehicle classification. In particular, a procedure to extract the vehicle signatures from the received signal is presented. The preliminary results obtained by means of an experimental setup developed and fielded at University of Rome "La Sapienza" show that different targets yield quite different signature shapes that can be fruitfully exploited by a classification stage according to a reasonable strategy.

This live demonstration presents a first-in-kind fully integrated Ku-band Synthetic Aperture Radar (SAR) transceiver chip in 65-nm CMOS that fits for micro-UAVs. The transmitter presents 13.3-dBm output power and 1.48 GHz chirp bandwidth centering at 15 GHz. The receiver front-end attains 23.5-dB gain, −33-dBm IPldB and 5.6-to-6.3dB noise figure. The receiver analog baseband achieves 0.68-to-9.8-MHz programmable passband and 55-dB variable gain range. The integrated ADC has 9.4-bit ENOB. The SAR chip achieves super-resolution of 11.2 cm and consumes only 260-mW power. The ranging and imaging functions of the prototype are showcased.

In this paper the development of a wearable 3D FMCW radar sensor system for firefighters to enhance eyesight in smoky surroundings during hazardous situations is described. In order to obtain a real-time capable, small and lightweight sensor, two orthogonal oriented frequency-scanning meander-line antennas are combined with small broadband 57 GHz to 63 GHz FMCW radar-modules. This arrangement is used to scan both directions, azimuth and elevation, in a fast time-multiplexed mode. The gathered time-domain datasets for both scanning directions are transferred to 2D projections. A following data-processing step merges both of these orthogonal images into a 3D-image of the monitored area. As no mechanical parts are involved, this very simple 2 Channel radar concept is suitable for a high degree of miniaturization. Integration of the whole system into a wearable system deployable for a broad field of applications in security and defense seems to be feasible.

International audience; Noise Radars are electromagnetic systems that use random signals for detecting and locating reflecting objects. Besides high performance with respect to the suppression of range ambiguity in the detection of targets and low range sidelobes, they also present an intrinsic property of low probability of interception by other systems, due to the stochastic nature of their transmit waveforms. Traditional methods and equipment are often ineffective to detect the presence of such kind of radars, both in time and frequency, since they generally adopt an ultra-wide bandwidth (UWB) configuration, spreading its power through a broad portion of the spectrum. Within this context, this paper proposes a probabilistic approach based on a statistical property of random vectors, the circularity, to detect the presence of pulses of this nature in the scenario under study.

By integrating the forward scattering radar (FSR) mode in passive radar can provide many advantages to the conventional passive radar system. The system can benefit from the enhancement in radar cross section (RCS), the low cost and the simple receiver system. In addition, the receiver circuit is less complicated as it does not require a synchronization signal from the transmitter. This paper presents the experimental results for ground target detection and classification in a passive radar system exploiting the effect of forward scatter. The latest 4G Long-Term Evolution (LTE) technology signal is used as the source of the signal transmission. The receiver, the detection and the classification system is explained. Results have shown the system's capability for detecting and classifying ground targets using the FSR technique in passive radar. Hence, it opens up a new frontier in passive radar that can be used for many applications, including border protection, microwave fences, building monitoring and etc.

The present work is going to investigate the potential benefits obtainable by taking advantage of the polarization diversity in a Passive Bistatic Radar (PBR) system exploiting Digital Video Broadcasting — Terrestrial (DVB-T) signals. In particular, a PBR demonstrator equipped with a surveillance array antenna able of simultaneously receiving both horizontal and vertical polarizations has been used to experimentally assess the radar performances as a function of the received polarization. The results obtained in a maritime scenario show a different target Signal-to-Interference-plus-Noise Ratio (SINR) variation as a function of the surveillance channel receiving polarization. Therefore, the availability of receiving both Horizontal (H) and Vertical (V) polarizations might improve the target detection performance if a suitable method of combining the signals received at different polarization is adopted.

Automotive radars in the 77–81 GHz band will be widely deployed in the coming years. This paper provides a comparison of the bi-phase modulated continuous wave (PMCW) and linear frequency-modulated continuous wave (FMCW) waveforms for these radars. The comparison covers performance, implementation and other non technical aspects. Multiple Input Multiple Output (MIMO) radars require perfectly orthogonal waveforms on the different transmit antennas, preferably transmitting simultaneously for fast illumination. In this paper, we propose two techniques: Outer code and Range domain, to enable MIMO processing on the PMCW radars. The proposed MIMO techniques are verified with both simulation and lab experiments, on a fully integrated deep-submicron CMOS integrated circuit designed for a 79 GHz PMCW radar. Our analysis shows that, although not widely used in the automotive industry, PMCW radars are advantageous for low cost, high volume single-chip production and excellent performance.

Pulse Doppler radars measure both the targets distance to the transceiver and their radial velocity, through estimation of time delays and Doppler frequencies, respectively. This digital processing is traditionally performed on samples of the received signal at its Nyquist rate, which can be prohibitively high. Overcoming the rate bottleneck, sub-Nyquist sampling methods have been proposed that break the link between radar signal bandwidth and sampling rate. In this work, we extend this concept to the slow time domain. We choose to transmit non-uniformly spaced pulses in one direction, thus allowing to reduce the average time-on-target by exploiting the complementary set of transmitted pulses in another direction. Both software and hardware simulations demonstrate reduced time-on-target and recovery of several delay-Doppler maps within the same coherent processing interval.

We consider radar systems with simultaneous dual-polarization reception capability. A new polarized radar model that includes the influence of the environmental disturbance factor on the received signal is established. It is demonstrated that the degree of polarization of the received signal is related to not only the signal-to-noise ratio but also to the electromagnetic waves' polarization state and to the environmental disturbance coefficient. The validity of the proposed model is demonstrated using real collected radar data.

This paper proposes a scheme to avoid mutual interference in frequency-modulated continuous-wave (FMCW) radar through the modulation of the frequency ramp with time. When multiple FMCW radars are being used simultaneously, the detection of beat frequency can be erroneous because the transmitted signals from other radars mutually interfere with the original signal. To detect the beat frequency of particular radar, we impose an orthogonal pattern in the change of frequency ramp slope. A single burst of FMCW radar comprises hundreds of frequency sweeps, and the slope of frequency ramp is modulated in a predefined matter. Then each radar has its own unique pattern in a spectrogram for a target; therefore the target range can be determined by observing the correlations between the obtained beat frequency spectrogram and a pattern simulated depending on distance. In this study, a sinusoidal pattern is employed to obtain orthogonality between radars. The simulation result shows that a target of interest could be successfully detected in an environment with mutual interference.

This article aims at describing our design of Frequency Modulated Continuous Wave (FMCW) Ground Penetrating Radar (GPR) design, that works at 2.4 GHz. Inspired from a similar radar design built by MIT Lincoln Laboratory [1], our radar maintains the same characteristic of cheapness, but it allows to choose and switch toward a larger number of modulation patterns for obtaining modulations such as saw tooth, triangular, Frequency-Shift Keying (FSK), and Stepped Frequency Continuous Wave (SFCW). In order to control the modulation pattern, and to receive the synchronization pulse together with the detected signal, the transceiver is connected to a laptop by means of Universal Serial Bus (USB), and audio port. Data elaboration can so make use of a custom software code, based on commercial software libraries, specific for data and image treatment. Moreover, the design of the antenna should be treated with care so that the signal reaches a larger depth even if it uses a higher frequency than usually.

Reconfigurable RF circuits are expected to become essential microwave components of next-generation wireless-communications and radar systems. In this paper, the usefulness of a tunable notch filter for interference mitigation is evaluated. In particular, the effects of an unintentional interference tone on the imaging performance of a coherent frequency-modulated-continuous-wave (FMCW) radar are assessed through simulation. The reported study serves to theoretically justify the operational benefits from the integration of reconfigurable notch filters into modern RF front-ends of coherent FMCW short-range radars. A specific experimental setup is also suggested for the practical verification of this analysis in a laboratory environment.

This paper presents a fully integrated active backscatter transponder for the use in a FMCW radar system for localization of passengers in sea in case of a ship sinking emergency. The active reflector tag is based on a cross-coupled oscillator circuit topology operating as a switched injection-locked oscillator (SILO). The circuit was implemented in a 180nm BiCMOS technology. Measurements resulted in an output power of 12.6dBm while consuming a DC power of 69mW, thus achieving a high efficiency of 26 %. Furthermore, the frequency tuning range is 18 %, the start-up time is 5.5 ns and the input referred noise power was measured to −79 dBm.

In this paper a highly integrated and compactly built FMCW radar system working at a center frequency of up to 240 GHz is presented. With an ultra wide tuning range of 40 GHz a range resolution down to 3.75 mm based on a −6 dB width of the target peak can be achieved, which enables this radar system for various high precision distance measurement and high resolution imaging applications. With the use of a highly integrated system architecture and on-chip antennas based on a single MMIC in combination with a PTFE lens antenna system, a very robust and compact realization is possible. Due to the full integration of all high frequency components, an open cavity QFN package can be used to mount the MMIC on a cost effective and easy-to-fabricate FR4 substrate, which also allows for quick and easy rework processes or chip replacements. The low power consumption of 3.5 W at a supply voltage of 5 V in addition to the compact, cost effective realization and the high resolution make this radar suitable for industrial applications.

A quadrature Doppler radar has been assembled using two single channel x-band MDU1020 radars. The combined radars can resolve null point distortion in physiological monitoring. This work demonstrates that physical offset between two single-channel radars can achieve proper phase shift for quadrature radar channels. Tests were performed with both mechanical targets and human subject.

Frequency modulated Continuous Wave (FMCW) is continuous wave RADAR widely used for Intelligent Adaptive Cruise Control (ACC) and Collision Warning System (CWS). The paper presents a design and simulation of millimeter wave FMCW RADAR. Paper introduces a mathematical modeling of a FMCW RADAR including its target model. Design of a 76.5 GHz FMCW RADAR & its target model by using Advanced Design System (ADS) software and target range & velocity at various conditions are employed in the simulated FMCW RADAR system to verify the operation of the system.

Radar has been widely used for military, security and rescue purposes and modern radar should be reconfigurable at multi-bands and have programmable central frequencies and considerable bandwidth agility. Microwave photonics or photonics-assisted radio-frequency technology is a unique solution to providing such capabilities. Here, we demonstrate an all-optical central-frequency-programmable and bandwidth-tailorable radar architecture that provides a coherent system and utilizes one mode-locked laser for both signal generation and reception. Heterodyning of two individually filtered optical pulses that are pre-chirped via wavelength-to-time mapping generates a wideband linearly chirped radar signal. The working bands can be flexibly tailored with the desired bandwidth at a user-preferred carrier frequency. Radar echoes are first modulated onto the pre-chirped optical pulse, which is also used for signal generation and then stretched in time or compressed in frequency several fold based on the time-stretch principle. Thus, digitization is facilitated without loss of detection ability. We believe that our results demonstrate an innovative radar architecture with an ultra-high-range resolution.

In this research, real time automatic frequency parameter extraction methods for electronic support systems are implemented on FPGA. The frequency parameter is extracted by using digital instantaneous frequency measurement (DIFM) and fast fourier transform (FFT) methods. Estimation performances of these two different methods for different type of radars at different signal to noise ratios (SNR) are analyzed. This design is implemented on Xilinx Virtex-6 based processing board that samples in 2.5 GHz. Experimental results of the design for FPGA implementation are presented.

In this paper a method for contour extraction of objects with a high degree of surface roughness in the range of 60 GHz Radar is presented. The proposed algorithm is based on an active contour model (snake) with external forces called component normalized gradient vector flow (CN-GVF). The snake algorithm extracts the contour of the object under test (OUT) based on wavefront Radar imaging methods. Experimental validations were performed with two fully integrated wideband frequency modulated continuous-wave (FMCW) single-chip Radar transceivers with an operational band from 57 GHz to 64 GHz, a corner cube retroreflector and a target object with a high degree of surface roughness.

Portable through wall radar display and control system is bridge between the radar signal process system and users. On the one hand, radar display and control system receives the origin image signal and present it to users after processed it, on the other hand, the system receives the users' instructions and passes it to the signal process system.

Design concepts and algorithms were developed to address the eye tracking analysis issues that arise when (1) participants interrogate dynamic multielement objects that can overlap on the display and (2) visual angle error of the eye trackers is incapable of providing exact eye fixation coordinates. These issues were addressed by (1) developing dynamic areas of interests (AOIs) in the form of either convex or rectangular shapes to represent the moving and shape-changing multielement objects, (2) introducing the concept of AOI gap tolerance (AGT) that controls the size of the AOIs to address the overlapping and visual angle error issues, and (3) finding a near optimal AGT value. The approach was tested in the context of air traffic control (ATC) operations where air traffic controller specialists (ATCSs) interrogated multiple moving aircraft on a radar display to detect and control the aircraft for the purpose of maintaining safe and expeditious air transportation. In addition, we show how eye tracking analysis results can differ based on how we define dynamic AOIs to determine eye fixations on moving objects. The results serve as a framework to more accurately analyze eye tracking data and to better support the analysis of human performance.

Vehicle speed detection in a highway can be performed using either laser or radio-frequency (RF) signals. Since laser speed detectors are prone to weather conditions and easy to jam, they are not preferred in practical applications. However, FMCW radars in the GHz frequencies provide excellent distance and speed measurement performance where high accuracy and reliability are needed. In this study, we propose RF front-end architectures for improved K band low probability intercept radar. To improve FM signal linearity, a predistorter based FM chirp signal generator is used. At the baseband, signal conditioning is adjusted for increasing radar range up to 1000 meters. To simulate the entire system, a pyramidal horn antenna is designed.

Passive radars, i.e., radars that use existing transmitters as illuminators of opportunity, have witnessed a fast progress in the last decade. Recent developments in many countries [1-5] refer to systems that use commercial transmitters (e.g., FM radio, DAB, DVB-T, GSM) and apply advanced signal processing technology to the received signal. The technology, known also by passive coherent location (PCL), is reaching its maturity stage, as some final products appear on the market [6, 7]. Most of these systems are stationary, ground-based passive radars.

We present the design and implementation of a portable, digital, real-time random noise radar system operating in the ultrahigh frequency range for through-the-wall detection and imaging. Noise radar technology is combined with modern digital signal processing approaches to architect a system to covertly perform range imaging of obscured stationary and moving targets as well as to detect the presence of humans via micro-Doppler detection combined with empirical mode decomposition. We model the propagation and sampling nonidealities in the system and propose techniques to overcome the effect of these nonidealities. Experimental results demonstrate the system's capability to image target scenes and characterize human activity from different stand-off distances.

We propose an algorithm for conversion of the data obtained by using a centimeter-wave radar designed to measure precipitation intensity to the data obtained by using a radar with a knife-edge beam. This opens up the way for simulation of satellite-based measurements with a knife-edge beam radar at the development stage with high confidence. Processing of the converted centimeter-wave radar data confirmed the efficiency of the algorithms used to reconstruct the dispersion of swelling tilts. A technique is proposed to form a panoramic image of the sea surface, and its operability is proved by analysis of the centimeter-wave radar data. This technique will allow one to reveal and study manifestations of large-scale wave processes on the sea surface.

The virtual target signal generator was developed to verify the shipborne tracking radar performance. It was used to DRFM(Digital RF Memory) method to generate the virtual moving targets. The target signal includes Doppler shift and RCS according to the target motion. And the signal generator can make jamming signal and clutter to test shipborne radar performance at real environmental condition. This paper described the functional diagram and the hardware configuration items to meet the test requirements for the tracking radar. And it showed the critical design points for the sub-systems. The signal generator which was developed in this paper shared the operational information of the radar with the radar command and control part. To test the frequency agility of the radar, it had the local oscillator which could do high speed frequency switching according to radar information. By communicating between the signal generator and the radar command and control part, the local oscillator of signal generator could be controlled every pulse. It reduced the instantaneous bandwidth of signal generator and minimized the spurious. So it lowered the probability of generating wrong targets.

In this paper, we discuss using field-programmable gate arrays (FPGAs) to process either time- or frequency-domain signals in human sensing radar applications. One example will be given for a continuous-wave (CW) Doppler radar and another for an ultrawideband (UWB) pulse–Doppler (PD) radar. The example for the CW Doppler radar utilizes a novel superheterodyne receiver to suppress low-frequency noise and includes a digital downconverter module implemented in an FPGA. Meanwhile, the UWB PD radar employs a carrier-based transceiver and a novel equivalent time sampling scheme based on FPGA for narrow pulse digitization. Highly integrated compact data acquisition hardware has been implemented and exploited in both radar prototypes. Typically, the CW Doppler radar is a low-cost option for single human activity monitoring, vital sign detection, etc., where target range information is not required. Meanwhile, the UWB PD radar is more advanced in through-wall sensing, multiple-object detection, real-time target tracking, and so on, where a high-resolution range profile is acquired together with a micro-Doppler signature. Design challenges, performance comparison, pros, and cons will be discussed in detail.

A new approach is proposed, namely CSSF MIMO radar, which applies the technique of step frequency (SF) to compressive sensing (CS) based multiple-input multiple-output (MIMO) radar. The proposed approach enables high resolution range, angle and Doppler estimation, while transmitting narrowband pulses. For the case of slowly moving targets, a technique is proposed that achieves significant complexity reduction by successively estimating angle-range and Doppler in a decoupled fashion.

Electronic ISBN: 978-1-4673-9526-7INSPEC Accession Number: 15805767; International audience; The concept of personal radar has recently emerged as an interesting solution for next 5G applications. In fact the high portability of massive antenna arrays at millimeter-waves enables the integration of a radar system in pocket-size devices (i.e. tablets or smartphones) and enhances the possibility to map the surrounding environment by guaranteeing accurate localization together with high-speed communication capabilities. In this paper we investigate for the first time the capability of such personal radar solution using real measured data collected at millimeter-waves as input for the mapping algorithm. Index Terms—Millimeter-wave propagation measurements, massive antenna arrays, indoor mapping, personal radar.

Phase coded radar signal is one of the pulse-pulse modulation signal in the radar system. Based on the characteristics of matched filtering, we theoretically analyze the basic principle of the phase coded compression radar system. In the Matlab platform, we set up a simulation model which is used for matching filter, when the radar transmitting signal is Barke code signal. The simulation results show that Echo signal can obtain certain pulse compression ratio. By the matched filter, the main lobe amplitude of 13 bits Barker code signal is 22 times the rate of side-lobe. 13 bits Barker codes by the matched filter have the maximum pulse compression ratio.

A prototype radar display unit was implemented using inexpensive off-the-shelf components, including a nonlinear estimation algorithm for the target tracking in a clutter environment. Two custom designed boards; an analog signal processing board and a DSP board, can be plugged into an expansion slot of a personal computer (PC) to form a maritime radar display unit. Our system provided all the functionality specified in the International Maritime Organization (IMO) resolution A422(XI). The analog signal processing board was used for A/D conversion as well as rain and sea clutter suppression. The main functions of the DSP board were scan conversion and video overlay operations. A host PC was used to run the tracking algorithm of targets in clutter, using the discrete-time Bayes optimal (nonlinear, and non-Gaussian) estimation method, and the graphic user interface (GUI) software for Automatic Radar Plotting Aid (ARPA). The proposed tracking method recursively found the entire probability density function of the target position and velocity by converting into linear convolution operations.

The purpose of this paper is to propose and analyze a novel field-capable method for measuring the spurious emission levels of weather radar. The method consists of time- and frequency-domain measurements. The time-domain measurements determine radar parameters, such as pulse duration, duty cycle, pulse repetition rate, and antenna rotation time; these are then used in the frequency-domain sweep measurements to obtain the relative level of radar spurious emissions in a given bandwidth with a minimum measurement time for a given average percentage of measured bandwidth. A large dynamic range (≥100 dB) is obtained by using a calibrated bandstop (BS) filter for controlled attenuation of the pulse spectrum at the nominal frequency. Results are shown for commercial weather radar at 5 GHz. This paper shows the need for radar signal filtering to prevent interference with other radio systems, such as radio local access network (RLAN) worldwide interoperability for microwave access (WiMAX), ultrawideband (UWB), and terrestrial radio relay systems, particularly those operating just above or below the nominal frequency of radar. The results give important information for radar system planning and communication network operations.

Trends in current weather research involve active phased-array radar systems that have several advantages over conventional radars with klystron or magnetron transmitters. However, phased-array radars generally do not have the same peak transmit power capability as conventional systems so they must transmit longer pulses to maintain an equivalent average power on target. Increasing transmits pulse duration increases range gate size but the use of pulse compression offers a means of recovering the otherwise lost resolution. To evaluate pulse compression for use in future weather radar systems, modifications to a weather radar simulator have been made to incorporate phase-coding into its functionality. Data derived from Barker-coded pulses with matched and mismatched filters were compared with data obtained from uncoded pulses to evaluate the pulse compression performance. Additionally, pulse compression was simulated using data collected from an experimental radar to validate the simulated results. The data derived from both experimental and simulated methods were then applied to a fuzzy logic tornado detection algorithm to examine the effects of the pulse compression process. It was found that the fuzzy logic process was sufficiently robust to maintain high levels of detection accuracy with low false alarm rates even though biases were observed in the pulse-compressed data.

Orthogonal frequency-division multiplexing (OFDM) signal coding and system architecture were implemented to achieve radar and data communication functionalities. The resultant system is a software-defined unit, which can be used for range measurements, radar imaging, and data communications. Range reconstructions were performed for ranges up to 4 m using trihedral corner reflectors with approximately 203 m of radar cross section at the carrier frequency; range resolution of approximately 0.3 m was demonstrated. Synthetic aperture radar (SAR) image of a single corner reflector was obtained; SAR signal processing specific to OFDM signals is presented. Data communication tests were performed in radar setup, where the signal was reflected by the same target and decoded as communication data; bit error rate of was achieved at 57 Mb/s. The system shows good promise as a multifunctional software-defined sensor which can be used in radar sensor networks.

We propose an approach to the problem of range coordinate registration (CR) for HF band over-the-horizon sky-wave radar (OTHR-SW) signals on a single pulse basis. The approach is based on the a priori knowledge of the displacement of the sea/land transitions within the area illuminated by the radar antenna beam. It takes advantage of the geomorphological structure of the surveillance area, which is exploited to build a surface correlation mask that is in turn used as a geographic reference for the received radar echo. The method is based on the maximization of the cross-correlation between the received radar echo and the surface mask signatures. We describe first an extended numerical model of the whole HF OTHR-SW scenario for simulating the received signal, then we show the results of the application of the method under simplifying operative hypotheses that allow to point out the minimum requirements in terms of received signal-to-noise ratio (SNR) and differential sea/land backscattering coefficient for achieving given accuracies in the range estimates.

Passive radars utilising illuminators of opportunity are being actively studied in the field of radar. In the last few years, many illuminator sources have been employed for passive radar applications. However, there have been no published results on the use of the long-term evolution (LTE) signal as a novel source for passive radar applications. For the first time an experimental investigation into the feasibility of LTE-based passive radars for detecting a moving target is presented. A theoretical analysis was conducted on a captured LTE signal in the atmosphere. This was then followed by a field experiment. The preliminary results show that the LTE signal is capable of being an illuminator for passive radars.

A real-time aircraft radar simulation applied in naval training is presented. The implemented algorithm works on a 3D synthesized environment, described by large sets of polygons—a typical scene can have a million of triangles—and the lobe is discretized with a cluster of rays. The radar display is recreated solving fast ray–polygon intersections (a variation of Ray-Shooting), and mapping them on the screen. This work proposes a new polygonal simplification method and a geometric classification algorithm in order to solve the intersections efficiently. This methodology leads to high fidelity images and real-time radar simulation, which operates at the specified 15 revolutions per minute rate. The results were tested with trained aircraft pilots. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 21: 606–613, 2013

The colocated uniform linear array (ULA) multiple-input multiple-output (MIMO) radar has been demonstrated to provide enhanced performance in theory. Similar to a bistatic radar, performance of the separated transmit/receive (STR) ULA-MIMO radar is affected not only by the transmitted multiple orthogonal waveforms, but also by the position of the target. In this correspondence, the ambiguity function of the STR-ULA-MIMO radar is investigated and the corresponding range-velocity ambiguity function (RVAF) is deduced. The range and velocity resolution of RVAF for the STR-ULA-MIMO radar is discussed. Because the shape of RVAF for the STR-ULA-MIMO radar is related to the position of the target, a new algorithm for adaptively designing the orthogonal frequency-hopping waveforms according to the position of the target is proposed. This algorithm improves the range and velocity resolution and the integrated sidelobe level (ISL) of the matched filter output at the corresponding position.

With limitation of frequency bandwidth, the range accuracy of typical radars is limited. In this paper, for short distance measurements, the use of an AM(Amplitude Modulated) radar which provides improved range accuracy is proposed. The AM radar signal consists of a carrier frequency signal and double-sideband components. The fabricated AM radar operates with +10 dBm output power and 35 dB receiver gain at 24.128 GHz center frequency with 20 MHz bandwidth, and the range accuracy is measured as .

In this chapter, results from simulation studies are presented which were conducted to assess the operational validity of the remote tower concept at a very early maturity level. The goal was to gain empirical evidence to lead further developmental activities and to learn about the critical design issues and human factors of the remote tower control concept. A high-fidelity simulation study with 12 tower controllers was conducted to assess the operational validity of an experimental workplace for remote tower control. The core of this workplace is a panoramic display, presenting high resolution video data of the remotely controlled airport. Besides the feasibility of the concept, the study addressed the relevance of the view outside the tower window and the benefit of information augmentation. Eye tracking, questionnaire, and interview data were gathered. Results indicate that the concept is valid for control of smaller airports with little air traffic. The augmentation of callsigns onto the video panorama reduced head-down times for the radar display.