Search

The article highlights the classified Wright Project's use of modified B-24D Liberator bombers equipped with advanced electronics for nighttime bombing raids during World War II. Topics covered include the project's deployment to the South Pacific, their innovative radar technology enabling precision attacks on Japanese shipping, and their crucial role in engagements with Japanese naval forces, showcasing their effective tactics under cover of darkness.

The article focuses on significant acquisitions and deliveries as well as orders of airborne radars, naval surveillance and fire control radar, and ground-based radar domain . Other information about investments continue in radars for combat aircraft and airborne surveillance radars is presented.

The article focuses on the progress in the use of radar to detect distant objects. Radar is known to be the accurate measurement of distance which is essential to the planning of space probes. Further advances in radar technology should make it possible to construct maps of the planets. Radar astronomy will not displace rocketry in the active exploration of space.

The article focuses on the millimeter and submillimeter range of radio microwaves. This type of radio microwave was utilized as radar during World War II. Radio waves in this range is capable of giving information about the shapes, sizes and other properties of submicroscopic particles of matter. Short radio wave is generated from centimeter waves and the development of harmonics. Then, it is sent through a waveguide where they are picked up by a cat whisker assembly.

The article offers information about defense and military technology, highlighting the development and emergence of radar technology. Topics being highlighted include potentially major breakthroughs regarding radar detection of stealth aircraft following a report that scientists from the University of Waterloo in Canada were developing so-called quantum radar technology that could detect stealth aircraft.

Presents information on military lobbying. Discussion on the 1989 invasion of Panama; Details of extra planes that would be needed mainly to hit enemy air defenses; Information on the circumvent ground radar; Details of impulse radar.

This paper presents a ultra-wideband (UWB) impulse radio timed-array radar utilizing time-shifted direct-sampling architecture. Time shift between the sampling time of the transmitter and the receiver determines the time of arrival (TOA), and a four-element timed antenna array enables beamforming. The different time shifts among the channels at the receiver determine the object's direction of arrival (DOA). Transmitter channels have different shifts, as well, to enhance spatial selectivity. The direct-sampling receiver reconstructs the scattered waveform in the digital domain, which provides full freedom to the backend digital signal processing. The on-chip digital-to-time converter (DTC) provides all the necessary timing with a fine resolution and wide range. The proposed architecture has a range and azimuth resolution of 0.75 cm and 3 degrees, respectively. The transmitter is capable of synthesizing a variety of pulses within 800 ps at a sampling rate of 10 GS/s. The receiver has an equivalent sampling frequency of 20 GS/s while supporting the RF bandwidth from 2 to 4 GHz. The proposed designs were fabricated in a 0.18- μm standard CMOS technology with a die size of 5.4×3.3 mm2 and 5.4×5.8 mm2 for the transmitter and the receiver, respectively. [ABSTRACT FROM AUTHOR]

Purpose – The purpose of this paper is to develop a new recognition system for identifying advanced radar emitter signals (RES). Design/methodology/approach – Initially, the framework of the new recognition system is outlined. Then, feature extraction using resemblance coefficient and wavelet packet decomposition, and feature selection based on quantum-inspired genetic algorithm, and a classifier combining K-means clustering, support vector machines and Mahalanobis distance are applied to actualize the recognition system. Finally, experiments are carried out on RES. Findings – A valid recognition system with its framework and implementation is presented to solve the difficult problem of advanced RES recognition. Research limitations/implications – Initial investigation is made on modern RES recognition. Further work may be done on decreasing the error rates and enhancing recognition efficiency. Real signals instead of simulated signals can be applied. Practical implications – The system developed here can be applied to electronic reconnaissance systems such as electronic support measures, electronic intelligence and radar warning receiver. Originality/value – The paper presents a novel recognition system and its implementation for modern RES. Extensive experiments conducted on 155 RES with eight intra-pulse modulations show the feasibility and validity of the introduced system. [ABSTRACT FROM AUTHOR]

High-accuracy pulse repetition interval (PRI) estimation is meaningful for enhancing the emitter-identification abilities of modern electronic intelligence (ELINT) systems. The maximum-likelihood estimate (MLE) of PRI can be obtained by locating the peak of periodogram of a point process signal used to model the sequence of the time-of-arrival (TOA) measurements. In this paper, a novel two-step numerical search strategy is proposed to search the peak of the periodogram to ensure maximum-likelihood estimation. Simulation results show that our algorithm outperforms the existing methods, especially under the condition of low signal-to-noise ratio (SNR) or high pulse-missing-rate. [ABSTRACT FROM AUTHOR]

In this paper, a new joint radar transmitter and receiver polarization optimization method is proposed based on the optimal detection criterion. First, a fully-polarimetric radar echo model is introduced, and the fully-polarimetric target detection algorithm is designed based on Neyman Pearson criterion, the detection performance is derived and analyzed. Then, a joint radar transmitter and receiver polarization optimization method is proposed to improve the capability of the target detection. Finally, the simulation results demonstrate that the target detection performance can be improved by using this algorithm remarkably. [ABSTRACT FROM AUTHOR]

The article outlines the best practices for the use of the Light Detection and Ranging (LIDAR) and SOnic Detection and Ranging (SODAR), and explains how to maximise the value from these remote sensing assets. It mentions that more developers are using the instruments to support wind resource assessments because they are easy to use and move from site to site. Also, they offer hub-height wind speeds and direction, wind shear and veer, and vertical wind speeds above heights of meteorological tower measurements. It notes that the use of the remote sensing date in an energy assessment will depend on the quality, quantity and representativeness of the validated data.

The article presents author's advices on how to upgrade boat electronics. It is noted that there are three things to be considered, the necessities for a basic system, pleasant add-ons, and whether one prefers to mix and match electronics from various manufacturers or to stick with one brand. A table is presented depicting the possible electronics that one can have based on a given budget, items include chartplotter, radar, and transducers from Garmin Corp., Raymarine PLC and Navico Ltd.

The article focuses on low probability of intercept (LPI) radars and its performance in naval operations. This radar is used to reduce the risk of detection and attack by using a form of pulse compression such as been used by PILOT of Saab AB and SCOUT of Thales Nederland BV. It also mentions the basic LPI techniques, the possible counter and counter-counter measures, and its other way of concealment.

Abstract: This work deals with the spectrum parameters estimation of a weather radar signal, namely velocity, variance and spectrum width. A new tool – based on the Ramanujan sums, , which come from the arithmetic functions of the number theory – has been introduced in signal processing. As compared to pulse pair and Fourier algorithms, new results have been obtained by the use of the Ramanujan-Fourier Transform (RFT) for the Doppler spectrum estimation of a real weather data provided by terminal pulse Doppler radar (WSR-88D). [Copyright &y& Elsevier]

The article focuses on the radar technology used by the U.S. Army against the Japanese air power during the World War II. It mentions that the air defense of the U.S. Army has its meager success against the Japanese bombers, causing them to design radars despite the lack of financial support. It highlights that the Army has finally acquired the SCR-270 Early Warning Radar and provided them an early warning and let them prepared for the upcoming air attackers.

The article discusses the functionalities and performance capabilities needed for the naval radar systems to operate in the littoral. It presents an overview of the research programs that formulated and demonstrated the advanced radar performance requirements needed to meet the challenging battle environments during littoral operations. It indicates that future naval radar systems will be provided by the high littoral performance capabilities following the suitable risk reduction demonstration.

The article presents the latest technological innovation of ImSAR's remote sensing technology. The company demonstrates on how the newly installed remote sensor, called synthetic-aperture radar (SAR), works. It provides details on SAR System (SARS) capacity to receive and trace signals and sound waves. Its range facility also becomes one of the critical examinations for it has limited range area to accommodate. SARS is first initiated in the 1950's but due to its critical mechanism; it was further given importance a decade later. Several SARS missions were facilitated by the National Aeronautics and Space Administration to assure its safeness.

The article presents information on an integrated wave monitoring network for the Hellenic Seas. It discusses the POSEIDON buoy wave monitoring system and the OKEANOS X-band wave radar network. The former is composed of 10 Sea-Watch buoys and 5 Wave-Scan buoys that are equipped with various sensors to monitor wave height and sea-surface conductivity among others. An OKEANOS station uses an X-band radar scanner and the Wavex software. Network integration is expected to improve marine meteorological services and oil spill contingency planning.

The article presents data obtained from the CODAROS SeaSonde High Frequency (HF) radar stations in the Galician coast which was severely affected by the Prestige oil spill in 2002. Two radars were placed in the lighthouses of Finisterre and Silleiro and used an operation frequency of 5 megahertz. Results show that using HF data significantly reduced the search and rescue areas by 49%. It concludes that trajectory models vastly improved when information on currents is integrated and that the radars show time availability higher than 98%.

The article presents a study that validates the measurement of the directional wave spectrum using high frequency (HF) radars. It provides examples of these validations through WEllen RAdar (WERA) and Pisces high frequency oceanographic radar systems using buoy and model data. A discussion on how to measure to measure the directional spectrum with HF radars is offered. Implications of the results for wave models are offered.

Abstract: We study the use of semi-sparse models, i.e., models having a few coefficients that are significantly larger than the rest, for estimation of range profiles in radar and other active sensing applications. The estimation of such range profiles is equivalent to estimation of a vector of regression coefficients in an underdetermined linear system. Each coefficient corresponds to a certain range bin in the illuminated area. If a range bin contains a target the reflections from that bin will, in some applications, result in a value of the corresponding coefficient which is significantly larger than the value corresponding to a target-free range bin. Under the assumption of a mixture of semi-sparse linear Gaussian models, we derive the minimum mean square error (MMSE) estimate of the range profile. We then find computationally efficient approximations of this MMSE estimate. As a by-product we also obtain a maximum a posteriori (MAP) target detector that does not require the choice of any detection threshold. The performances of our methods are illustrated via numerical examples. [Copyright &y& Elsevier]

Abstract: This paper extends previous Sensor Resource Management (SRM) work by addressing information flow from sensor inputs to SRM, through four levels of the US DoD’s Joint Directors of Laboratories (JDL) sensor fusion model. The method flexibly adapts to several domains/problems. Human situation awareness information needs are linked to sensor control in a manner similar to perception management. The key to effective integration of JDL levels is the timely determination of the highest priorities via threat projection accomplished via Probabilistic Accumulative Situation Calculus (PASC), which quantifies threat intent using an appropriate level of automated context-based reasoning. The accuracy of the threat projection is improved over time using self-learning techniques. The multiple sensor system levels are unified primarily using the structure of quantified priorities. Algorithms are presented for a radar sensor resource allocation and adjustment method in which the dwell time per track parameter is the key radar sensor resource to be managed. A developed application of the method to an Integrated Air Defense System (IADS) sensor system problem is detailed, with simulation results shown to demonstrate the effectiveness of the method. [Copyright &y& Elsevier]

The article evaluates electronic systems and units that are expected to make a big impact on navigation and safety in 2008, including digital radar technology, the Sim-Net-ready NX40 GPs chart plotter from Simrad and the GPM400 module, a black-box processor from Raymarine.

The article features the state-of-the-art naval radars. Most of the naval vessels have their radars used for warfare and defense and these innovative and new generation of naval radars include SAMPSON multi-function active phased array radar in HMS Daring, SEA GIRAFFE AMB multi-role radar in Visby class corvette, and the SMART-L radar in LCF frigate.

Synthesizers for the generation of frequency- or phase-modulated signals are required in communications, sensing, and many other fields and applications. The widespread use of phase-locked loops (PLLs) as major building blocks in current systems requires accurate models and methods for eliminating the influence of statistical and deterministic errors in the synthesized signals. We propose a novel iterative phase-error-measurement and -compensation procedure applicable in PLL-based synthesizers, for which the mathematical background is presented, and a detailed algorithmic description is given in this work. From a mathematical PLL system model and its response to a periodic excitation by the modulating signal, a method for measuring the instantaneous output signal phase and the actual transfer function of the PLL is derived. It is shown how this knowledge can advantageously be used for pre-distorting the synthesizer input signal to eliminate deterministic errors and to obtain an accurate output phase curve. [ABSTRACT FROM AUTHOR]

The article discusses the developments of Radio Direction And Ranging (RADAR) from World War II in 1939-1945 until 21st century. It was emphasized that radar started with antennas sized several tenths of meters and magnetrons to generate frequencies which evolved into digital form with small fixed faces and electronically switched beams for tasks versatility. The Raytheon engineers have produced APG-65, a multi-function radar which could do both air-to-air missile guidance and ground mapping.

The article reports on the significance of utilizing Automatic Identification Systems (AIS) and Vessel Traffic Systems (VTS) in naval ships in the U.S. The AIS and VTS are designed with high-technologies that provide accurate information and data to warships as well as help towards effective operation of marines. In addition, the integration of radar systems contribute towards easy transmission of relevant data and processing capability. Also, both systems promote safe navigation for all ships.

The article provides information on the bistatic and multistatic radar systems used by the U.S. military. It does not require expensive transmitters and are relatively immune to physical and electronic attack due to its inherent passivity and distributed nature. It is claimed that this radar system will be able to detect stealthy targets.

Abstract: This paper examines the problem of adaptive beam scheduling to minimise target tracking error with a phased array radar. It is shown that this can be posed in a framework that is similar to a particular type of dynamic programming problem known as the restless bandit problem. We will show that when the problem is put in this framework it has an indexable solution under certain circumstances. [Copyright &y& Elsevier]

This article focuses on the fighters and radars that could eventually gain active electronically scanned array (AESA) airborne electronic attack capabilities by forecasting the 10-year future of the fighter radar market as of February 2006. The article also predicts the market shares of U.S. companies that would benefit from the massive funding likely to follow today's initial nonkinetic radar weapon concept studies.

The article focuses on the industrial uses of ground penetrating radar (GPR). Many years ago, GPR had been relegated to the world of academic research and very specialized applications, but it is now recognized as a practical tool for mainstream testing, mapping and locating of subsurface and infrastructural discontinuities. The technologically advanced GPR products being delivered to the current markets are aided by programmable computer chips, improved analysis software and years of knowledge. GPR is one of the safest and user-friendly non-destructive testing tools available.

Abstract: Embedded software processing requirements will exceed 1 trillion operations per second in the 2005–2010 time frame. Consequently, efficient use of processors and memory, at all levels, is essential. In many defense environments, e.g., radar, as well as medical and other real-time embedded systems, operations are primarily array-based. Although languages support high level, monolithic, array based computation through classes, functions, templates (C++), and grammars (Fortran 95, ZPL), limited optimizations occur to eliminate array valued temporaries, which for embedded real time systems, is enormous. Without an underlying theory of arrays, e.g., an algebra and index calculus, it is difficult, if not impossible to provide such optimizations. This paper presents a Mathematics of Arrays and Psi Calculus. Together they are used to reason about array based computation in radar; the algorithm, decomposition, mapping to processors and memory, performance. [Copyright &y& Elsevier]

In situ dielectric constant variations of hot mix asphalt layers versus time were studied. The dielectric constant of the considered hot mix asphalt layers were nondestructively estimated using ground penetrating radar data collected over a controlled test pavement—the Virginia Smart Road. It was found that the dielectric constant of various hot mix asphalt layers decreased linearly with time but remained within the typical limits. For all tested hot mix asphalt types, the variation slope was relatively small, with a maximum decrease of approximately 0.8 over a one year period. The main cause of the hot mix asphalt dielectric constant decrease versus time was found to be the aging of the asphalt binder, which causes the reduction of its susceptibility to be polarized by the applied electric fields, thus decreasing its ability to store electric energy and consequently decreasing its dielectric constant. [ABSTRACT FROM AUTHOR]

Reports on the installation of the Lockheed Martin SPY-1, phased-array radar in Norman, Oklahoma to look for tornadoes in the region. Development of the Tactical Environmental Processor, a weather-detection system; Utilization of the TEP; Statement of Tom McNellis, manager of the radar technology program office at Lockheed Martin Maritime Systems and Sensors; Usability of the computer models to make weather predictions.

Shipboard/landbased radars require adaptive signal processing to suppress interference consisting of external directional jammers and background clutter. Using a structured covariance matrix form, which includes partial knowledge of the internal noise and temporal clutter covariance matrix, a fast converging adaptive signal processor is developed that can take two forms: (1) simultaneously adaptively weight the spatial (antenna elements) and temporal (pulses) inputs to form an output or (2) adaptively weight the spatial (antenna elements) inputs and nonadaptively pulse-Doppler process thereafter to form an output. In either case it is shown using a simplistic mismatched clutter/jamming model that the convergence performance (within 3 dB of optimum) of the new adaptive processors (AP) is almost the same as that of the fast converging processor when no clutter was present in the data inputs. For both cases, the algorithms converge for typical scenarios under consideration in just a few independent sample vectors per input channel. [Copyright &y& Elsevier]

This article focuses on Russia's early warning system radars. In an incident Norwegian and the U.S. scientists launched the Black Brant XII sounding rocket from a small island off Norway's northwest coast on January 25, 1995, they intended for it to harmlessly collect scientific data about the Northern Lights. But when Russia's early warning system radars detected the rocket, they generated an alarm that entered the nuclear forces command and control system and reached the highest levels of government. A Cold War hangover, launch-on-warning was designed to provide additional protection to nuclear forces by ensuring that a retaliatory attack could be initiated before a first strike obliterated its targets. Implementing launch-on- warning required substantial investment in a network of early warning radars and satellites-plus a command and control system that would allow missiles to be on constant "hair-trigger alert."

The article informs that in the ultimate flight simulation, everything's real but the view from the cockpit. This is NASA's Synthetic Vision Systems (SVS), a technology designed to fundamentally change how people look at the world. Electronic screens such as head-up displays, a transparent panel mounted in front of the windscreen that allows pilots to see their instruments while keeping an eye on goings-on in the real world, have been around for years. SVS, however, dispenses with the real entirely. Instead it shows the pilot a highly detailed simulation of the world outside created by fusing real-time images from radar, infrared sensors and a huge 3D digital map. With this system, clouds and thunderstorms melt away. Night becomes day. Every twist and turn of a flight, and every potential hazard, can be pointed out in big, red, flashing letters.

Reports on new technology called Celldar, a combination of cellular technology and radar. Development by Roke Manor Research Ltd. in England; Difference between Celldar and radar; Passive system with benefits for the military because of invisibility to anti-radar weapons; Various uses for the technology; Inexpensiveness of passive systems; Robot spy plane and AWACS capabilities; Civilian applications; Possible alternative to GPS systems; Suggestion of use to support pay-for-use road tax plans.

The article offers information on several electronic fishing radar equipments including Raymarine radar tablet from Raymarine PLC, Fusion 700 and 205 series marine entertainment systems from Fusion Electronics Ltd. and the Cobra HH450 Dual VHF/GMRS radio from Cobra Co.

Reveals the true face of the planet Venus from radar images provided by the spacecraft Magellan. The yellow clouds of carbon dioxide that obscure the planet; Magellan's mapping of every bit of Venus; Surface features of Venus; Volcanic evidence; Details.

Recounts how Britain used a newfangled system called radar to defend itself against German bombers 50 years ago. Development of Radio Detecting and Ranging (RADAR); Role of Robert Watson Watt and the radar team; Hermann Goring's Luftwaffe strategy; Radar's role in World War II.

The article offers a look at the developments in radar systems in relation to the unmanned aerial vehicle (UAV) industry in the U.S. as of December 2013. Topics discussed include the small tactical radar (STR) system, the ground moving target indication (GMTI) system, and the Foliage Penetration (FOPEN) radar system. Also mentioned are General Atomics Aeronautical Systems Inc. (GA-ASI), the integration of optronics in radars, and the defense electronics specialist Cassidian.

The article discusses the importance of keeping security surveillance equipment updated to protect an airport's perimeters. It features the Navtech Radar introduced by Valencia Airport in Spain to ensure the safety of the premises. It notes the incidents of intruders breaking through airport perimeter fencing for criminal purposes which only shown the severe weaknesses in the monitoring and protection of entire airport complexes.

The article reports on the development of gadgets such as radars, sonar, mobile telephone, and magnetic mine at the Bell Telephone Laboratories in the U.S. From the British technology magnetron, the modern radars was developed. The author explores the advantages and enhancements in these technologies.

The article analyzes the worthiness of the sonar and the radars systems. Some evidence suggests that a submarine may pick up its own noisy engines at full speed. Or its own wake in the zigzag dodging to escape enemy boats. The Defense Department still does not explain what the "overeager sonarmen" of the "Turner Joy" actually saw. Sonar operators today face even tougher tasks. Nuclear submarines slink quietly through ocean depths and sonar strains harder to detect faint echoes in the surprisingly noisy world of the sea. On top of this, the enemy has an arsenal of sound decoys and counter measures to mask sub and torpedo noises. These sound "spooks" create false targets, blot out the sounds of the real threat.

The article report developments in the study of angels which is a clouds of dots that appears from time to time on powerful radar sets employing higher frequencies. Some scientist suggested that various meteorological conditions is the responsible for the angels. Three British workers have studied the dots and concluded that angels are simply radar pictures of migrating birds, chiefly small songbirds.

The article offers information on the Thunderhead Balloon System, the Lightning Balloon System and Vista F10 radar system from Raven Aerostar.

The article reports that Northrop Grumman Corp.'s E-8C Joint Surveillance Target Attack Radar System, or Joint STARS, has proven its mettle and usefulness for more than two decades and through multiple conflicts. Joint STARS has two primary functions, said Dave Nagy, vice president of Northrop Grumman's Military Aircraft Systems business development.

The article focuses on the Advanced Capability Build 12 (ACB12) upgrade which will blend open architecture with a fully integrated ballistic-missile defense capability on Aegis ships in the U.S. It says that the U.S. Navy will install the ACB12 upgrade on 14 cruisers and the first 28 Arleigh Burke destroyers in the beginning of 2012. It also mentions that newer destroyers will feature integrated S- and X-band radars.