Optmized patch-like antennas for through the wall radar imaging and preliminary results with frequency modulated interrupted continuous wave

This paper presents optimized patch-like antennas for Through The Wall Imaging (TTWI) radar applications in the frequency range 0.5-2 GHz, and preliminary results using Frequency Modulated Interrupted Continuous Waveform (FMICW). Results of numerical simulations using basic models of the antenna are presented. The antenna optimization was aimed at making the radiation pattern more directional by focusing the energy in a single lobe to be directed towards the wall and the targets to be detected. The optimized antenna was manufactured and its measured parameters are compared with the simulated results which show good agreement. Some preliminary results from the FMICW radar system using this antenna are presented

Review of radar classification and RCS characterisation techniques for small UAVs or drones

This review explores radar-based techniques currently utilised in the literature to monitor small unmanned aerial vehicle (UAV) or drones; several challenges have arisen due to their rapid emergence and commercialisation within the mass market. The potential security threats posed by these systems are collectively presented and the legal issues surrounding their successful integration are briefly outlined. Key difficulties involved in the identification and hence tracking of these `radar elusive' systems are discussed, along with how research efforts relating to drone detection, classification and radar cross section (RCS) characterisation are being directed in order to address this emerging challenge. Such methods are thoroughly analysed and critiqued; finally, an overall picture of the field in its current state is painted, alongside scope for future work over a broad spectrum

Multistatic radar classification of armed vs unarmed personnel using neural networks

This paper investigates an implementation of an array of distributed neural networks, operating together to classify between unarmed and potentially armed personnel in areas under surveillance using ground based radar. Experimental data collected by the University College London (UCL) multistatic radar system NetRAD is analysed. Neural networks are applied to the extracted micro-Doppler data in order to classify between the two scenarios, and accuracy above 98% is demonstrated on the validation data, showing an improvement over methodologies based on classifiers where human intervention is required. The main advantage of using neural networks is the ability to bypass the manual extraction process of handcrafted features from the radar data, where thresholds and parameters need to be tuned by human operators. Different network architectures are explored, from feed-forward networks to stacked auto-encoders, with the advantages of deep topologies being capable of classifying the spectrograms (Doppler-time patterns) directly. Significant parameters concerning the actual deployment of the networks are also investigated, for example the dwell time (i.e. how long the radar needs to focus on a target in order to achieve classification), and the robustness of the networks in classifying data from new people, whose signatures were unseen during the training stage. Finally, a data ensembling technique is also presented which utilises a weighted decision approach, established beforehand, utilising information from all three sensors, and yielding stable classification accuracies of 99% or more, across all monitored zones

Evaluation of Moderate and Low-Powered Lasers for Dispersing Double-Crested Cormorants from Their Night Roosts

The double-crested cormorant (Phalacrocorax auritus) is the primary avian predator on the southern catfish industry, estimated to cause $5 million in damage per year. To date, the most effective strategy for alleviating cormorant depredations in areas of intensive catfish production is coordinated dispersal of cormorant night roosts with pyrotechnics. Many of these night roosts are located in waterfowl refuges or wetland habitat leased for waterfowl hunting. Thus, there is an increasing concern about the effects of cormorant harassment efforts on waterfowl and other wildlife inhabiting these sites in cypress-swamp habitat. To address the need for a roost harassment device that was more species-specific, we evaluated two commercially available low- to moderate-powered lasers in a series of large-pen and field trials for their effectiveness in moving cormorants from test ponds and dispersing cormorants from their night roosts, respectively. In pen trials, laser beams directed at small groups of captive birds produced negligible effects, suggesting that the laser light was not highly aversive. This was consistent with a series of veterinary investigations suggesting no detectable ocular damage to cormorant eyes directly exposed to a selected laser at varying distances down to 1 m. During field trials both lasers, directed at roost trees after sunset, were consistently effective in dispersing cormorants in 1 to 3 evenings of harassment and is comparable to the harassment effort needed with pyrotechnics. Because laser treatment is completely silent and can be directed selectively at cormorants, these devices may be extremely useful for dispersing cormorants in sites where disturbance of other wildlife is a concern. Advantages and disadvantages of lasers relative to pyrotechnics are discussed

First Measurements with NeXtRAD, a Polarimetric X/L Band Radar Network

NeXtRAD is a fully polarimetric, X/L Band radar network. It is a development of the older NetRAD system and builds on the experience gained with extensive deployments of NetRAD for sea clutter and target measurements. In this paper we will report on the first measurements with NeXtRAD, looking primarily at sea clutter and some targets, as well as early attempts at calibration using corner reflectors, and an assessment of the polarimetric response of the system. We also highlight innovations allowing for efficient data manipulation post measurement campaigns, as well as the plans for the coming years with this system

Valores fisiológicos en sangre y orina de rana toro en cautiverio, <i>rana catesbeiana</i> (<i>Anura: ranidae</i>)

Con el propósito de obtener valores sanguíneos y urinarios de referencia, 302 muestras de ejemplares sanos de Rana catesbeiana del nordeste argentino (9-21 meses de edad, 50% de cada sexo), fueron analizadas por espectrofotometría, electroforesis, densitometría, refractometría y microscopía. Fueron obtenidos intervalos de confianza (p<0,05) para hematocrito (28,6-31,6%), eritrocitos (0,40-0,44 T/L), VCM (686-732 fL), hemoglobina (6,41-7,20 g/dL), HCM (151-164 pg), CHCM (22,6-24,0%), leucocitos (18,7-22,3 G/L), neutrófilos (58,4-63,4%), linfocitos (23,9-29,8%), monocitos (2,1-3,8%), eosinófilos (4,6-7,0%), basófilos (2,9-4,1%), fibrinógeno (0,59-0,99 g/dL), proteínas totales (4,19-4,49 g/dL), albúmina (1,49-1,67 g/dL), globulinas (2,64-2,97 g/dL), creatinina (4,09-5,56 mg/L), urea (76,1-92,4 mg/L), ácido úrico (11,5-15,4 mg/L), triglicéridos (0,34-0,52 g/L), colesterol total (0,56-0,67 g/L), C-HDL (0,03-0,05 g/L), C-LDL (0,34-0,44 g/L), alfa lipoproteína (6,01-8,67%), beta lipoproteína (91,3-93,9%), glucosa (0,45-0,54 g/L), Na (116-121 meq/L), K (3,42-3,81 meq/L), Cl (100-116 meq/L), Ca (7,98-8,61 mg/dL), P (8,31-9,36 mg/dL), Mg (2,26-2,55 mg/dL), Fe (105- 178 ug/dL), ALP (144-170 UI/L), ALT (10,0-14,8 UI/L), AST (42,8-53,4 UI/L), GGT (7,8-10,6 UI/L), LDH (99-135 UI/L), CHE (151-185 UI/L), CPK (365-500 UI/L), tiempo de sangría (289- 393s), tiempo de coagulación (452-696s), tiempo de protrombina (76-128s), densidad urinaria (1,0061-1,0089) y pH urinario (6,38-6,96). Algunos intervalos fueron semejantes a los obtenidos en anfibios, aves o mamíferos, pero otros resultaron muy diferentes. Ciertos parámetros registraron variaciones fisiológicas atribuibles a edad, sexo, estación del año y sistema de manejo y alimentación. Se resalta la utilidad de los parámetros estudiados para evaluar estados sanitario, metabólico y nutricional de la rana toro en cautiverio.Samples of healthy Rana catesbeiana (302 specimens, 9-21 months-old, 50% each sex) from the north-east of Argentina, were analyzed by spectrophotometry, electrophoresis, densitometry, refractometry and microscopy in order to obtain blood and urine reference values. Confidence intervals (p<0.05) for PCV (28.6-31.6%), RBC (0.40-0.44 T/L), MCV (686- 732 fL), hemoglobin (6.41-7.20 g/dL), MCH (151-164 pg), MCHC (22.6-24.0%), WBC (18.7- 22.3 G/L), neutrophils (58.4-63.4%), lymphocytes (23.9-29.8%), monocytes (2.1-3.8%), eosinophils (4.6-7.0%), basophils (2.9-4.1%), fibrinogen (0.59-0.99 g/dL), total protein (4.19-4.49 g/dL), albumin (1.49-1.67 g/dL), globulins (2.64-2.97 g/dL), creatinine (4.09-5.56 mg/L), urea (76.1-92.4 mg/L), uric acid (11.5-15.4 mg/L), triglycerides (0.34-0.52 g/L), total cholesterol (0.56-0.67 g/L), HDL-C (0.03-0.05 g/L), LDL-C (0.34-0.44 g/L), alpha lipoprotein (6.01-8.67%), beta lipoprotein (91.3-93.9%), glucose (0.45-0.54 g/L), Na (116-121 meq/L), K (3.42-3.81 meq/ L), Cl (100-116 meq/L), Ca (7.98-8.61 mg/dL), P (8.31-9.36 mg/dL), Mg (2.26-2.55 mg/dL), Fe (105-178 ug/dL), ALP (144-170 IU/L), ALT (10.0-14.8 IU/L), AST (42.8-53.4 IU/L), GGT (7.8- 10.6 IU/L), LDH (99-135 IU/L), CHE (151-185 IU/L), CPK (365-500 IU/L), bleeding time (289- 393s), coagulation time (452-696s), prothrombin time (76-128s), urinary density (1.0061- 1.0089), and urinary pH (6,38-6.96), were obtained. Some intervals were similar to those obtained in amphibians, birds or mammals, but others were very different. Physiological variations attributable to age, sex, season, and handling and feeding system, were registered on certain parameters. The usefulness of the parameters studied to evaluate sanitary, metabolic and nutritional state on captive bullfrog should be emphasized.Facultad de Ciencias Veterinaria

Valores fisiológicos en sangre y orina de rana toro en cautiverio, <i>rana catesbeiana</i> (<i>Anura: ranidae</i>)

Con el propósito de obtener valores sanguíneos y urinarios de referencia, 302 muestras de ejemplares sanos de Rana catesbeiana del nordeste argentino (9-21 meses de edad, 50% de cada sexo), fueron analizadas por espectrofotometría, electroforesis, densitometría, refractometría y microscopía. Fueron obtenidos intervalos de confianza (p<0,05) para hematocrito (28,6-31,6%), eritrocitos (0,40-0,44 T/L), VCM (686-732 fL), hemoglobina (6,41-7,20 g/dL), HCM (151-164 pg), CHCM (22,6-24,0%), leucocitos (18,7-22,3 G/L), neutrófilos (58,4-63,4%), linfocitos (23,9-29,8%), monocitos (2,1-3,8%), eosinófilos (4,6-7,0%), basófilos (2,9-4,1%), fibrinógeno (0,59-0,99 g/dL), proteínas totales (4,19-4,49 g/dL), albúmina (1,49-1,67 g/dL), globulinas (2,64-2,97 g/dL), creatinina (4,09-5,56 mg/L), urea (76,1-92,4 mg/L), ácido úrico (11,5-15,4 mg/L), triglicéridos (0,34-0,52 g/L), colesterol total (0,56-0,67 g/L), C-HDL (0,03-0,05 g/L), C-LDL (0,34-0,44 g/L), alfa lipoproteína (6,01-8,67%), beta lipoproteína (91,3-93,9%), glucosa (0,45-0,54 g/L), Na (116-121 meq/L), K (3,42-3,81 meq/L), Cl (100-116 meq/L), Ca (7,98-8,61 mg/dL), P (8,31-9,36 mg/dL), Mg (2,26-2,55 mg/dL), Fe (105- 178 ug/dL), ALP (144-170 UI/L), ALT (10,0-14,8 UI/L), AST (42,8-53,4 UI/L), GGT (7,8-10,6 UI/L), LDH (99-135 UI/L), CHE (151-185 UI/L), CPK (365-500 UI/L), tiempo de sangría (289- 393s), tiempo de coagulación (452-696s), tiempo de protrombina (76-128s), densidad urinaria (1,0061-1,0089) y pH urinario (6,38-6,96). Algunos intervalos fueron semejantes a los obtenidos en anfibios, aves o mamíferos, pero otros resultaron muy diferentes. Ciertos parámetros registraron variaciones fisiológicas atribuibles a edad, sexo, estación del año y sistema de manejo y alimentación. Se resalta la utilidad de los parámetros estudiados para evaluar estados sanitario, metabólico y nutricional de la rana toro en cautiverio.Samples of healthy Rana catesbeiana (302 specimens, 9-21 months-old, 50% each sex) from the north-east of Argentina, were analyzed by spectrophotometry, electrophoresis, densitometry, refractometry and microscopy in order to obtain blood and urine reference values. Confidence intervals (p<0.05) for PCV (28.6-31.6%), RBC (0.40-0.44 T/L), MCV (686- 732 fL), hemoglobin (6.41-7.20 g/dL), MCH (151-164 pg), MCHC (22.6-24.0%), WBC (18.7- 22.3 G/L), neutrophils (58.4-63.4%), lymphocytes (23.9-29.8%), monocytes (2.1-3.8%), eosinophils (4.6-7.0%), basophils (2.9-4.1%), fibrinogen (0.59-0.99 g/dL), total protein (4.19-4.49 g/dL), albumin (1.49-1.67 g/dL), globulins (2.64-2.97 g/dL), creatinine (4.09-5.56 mg/L), urea (76.1-92.4 mg/L), uric acid (11.5-15.4 mg/L), triglycerides (0.34-0.52 g/L), total cholesterol (0.56-0.67 g/L), HDL-C (0.03-0.05 g/L), LDL-C (0.34-0.44 g/L), alpha lipoprotein (6.01-8.67%), beta lipoprotein (91.3-93.9%), glucose (0.45-0.54 g/L), Na (116-121 meq/L), K (3.42-3.81 meq/ L), Cl (100-116 meq/L), Ca (7.98-8.61 mg/dL), P (8.31-9.36 mg/dL), Mg (2.26-2.55 mg/dL), Fe (105-178 ug/dL), ALP (144-170 IU/L), ALT (10.0-14.8 IU/L), AST (42.8-53.4 IU/L), GGT (7.8- 10.6 IU/L), LDH (99-135 IU/L), CHE (151-185 IU/L), CPK (365-500 IU/L), bleeding time (289- 393s), coagulation time (452-696s), prothrombin time (76-128s), urinary density (1.0061- 1.0089), and urinary pH (6,38-6.96), were obtained. Some intervals were similar to those obtained in amphibians, birds or mammals, but others were very different. Physiological variations attributable to age, sex, season, and handling and feeding system, were registered on certain parameters. The usefulness of the parameters studied to evaluate sanitary, metabolic and nutritional state on captive bullfrog should be emphasized.Facultad de Ciencias Veterinaria

Measurements of multistatic X&L band radar signatures of UAVs

This paper illustrates the results of a series of measurements of multistatic radar signatures of small UAVs at L and X band. The system employed was the multistatic multiband radar system, NeXtRAD, consisting of one monostatic transmitter-receiver and two bistatic receivers. Results demonstrate the capability of the system of recording bistatic data with baselines and two-way bistatic range of the order of few kilometres

Measurements and discrimination of drones and birds with a multi‐frequency multistatic radar system

This article presents the results of a series of measurements of multistatic radar signatures of small UAVs at L‐ and X‐bands. The system employed was the multistatic multiband radar system, NeXtRAD, consisting of one monostatic transmitter‐receiver and two bistatic receivers. NeXtRAD is capable of recording simultaneous bistatic and monostatic data with baselines and two‐way bistatic range of the order of a few kilometres. The paper presents an empirical analysis with range‐time plots and micro‐Doppler signatures of UAVs and birds of opportunity recorded at several hundred metres of distance. A quantitative analysis of the overall signal‐to‐noise ratio is presented along with a comparison between the power of the signal scattered from the drone body and blades. A simple study with empirically obtained features and four supervised‐learning classifiers for binary drone versus non‐drone separation is also presented. The results are encouraging with classification accuracy consistently above 90% using very simple features and classification algorithms

Measurements of the Multistatic X&L Band Radar Signatures of UAVS

This paper illustrates the results of a series of measurements of multistatic radar signatures of small UAVs at L and X band. The system employed was the multistatic multiband radar system, NeXtRAD, consisting of one monostatic transmitter-receiver and two bistatic receivers. Results demonstrate the capability of the system of recording bistatic data with baselines and two-way bistatic range of the order of few kilometres