Papers by Keyword: Radar

Abstract: The main technical requirements for the development of an electromagnetic detection method for explosive materials are considered. The main elements of interference that increase the detection error are classified. The probability of detecting explosives at different soil depths is modeled. It was found that the frequency of the scanning signal has the greatest influence. Thus, reducing the scanning frequency increases the probability of detecting an object. However, reducing the irradiation frequency is limited by the resolution for objects of a given size. It is shown that reducing the dielectric constant of the soil does not lead to satisfactory detection probabilities even in the upper soil layer. In the size range of real explosives (0.1–0.5 m), the detection probability decreases by 10-25%. The analysis of the characteristic time signatures of explosives imitations showed that the development of a database of such signatures will reduce the number of false signals. An algorithm for the implementation of the method of electromagnetic detection of explosives consisting of 18 functional blocks and three logical blocks has been developed. The obtained results made it possible to describe the procedure for detecting explosive materials in a contaminated area. The use of the obtained results in humanitarian demining will increase the speed of surveying the territory, increase the probability of detecting explosive objects and reduce the risk of injury to personnel conducting humanitarian demining.

Abstract: The challenges of vision sensors during poor visibility or when faced with transparent objects, along with RADAR sensors’ susceptibility to degradation and jamming constitute major aspects of limitations in object detection systems. Researchers are continuously exploring better methods and materials for object detection to develop fully autonomous vehicles capable of avoiding collisions in scenarios where distance and speed permit. This paper examines the accuracy of measurements taken by the Level metre Ultrasonic sensor, range finder LiDAR and a radar sensor when targeting objects with contrasting levels of visibility. The target objects considered for this experiment are black and light brown coloured plywood and transparent glass; these objects represent opposites in terms of visibility. Results for range finder LiDAR showed minimal variations with the plywood objects, but recorded much higher error margins when targeting the glass object and failed to detect the glass object at a range of 0.6 metre; which was the shortest distance considered for this paper. The ultrasonic sensor recorded an average error margin of 2.03% at distances between 0.6 and 15 metres but recorded an average error margin of 42.48% at 20 metres. It can be stated that for collision avoidance systems, a suite of sensors, including Ultrasonic, LiDAR and RADAR sensors, can effectively detect objects in their path with an accuracy above 97% without the use of vision sensors.

Abstract: An improved rain detection system has been developed using a marine radar. The rain detection system is composed of a Furuno 1932 Mark II marine radar (radar scanner and display units), a radar control circuit, a signal conditioning circuit, an analog to digital converter (ADC), and a computer with a graphical user interface (GUI). The combination of the microcontroller and optocoupler in the radar control circuit was able to replace the omnipad and pushbutton control and it was also employed to activate the radar and the sector blanket mode. The signal conditioning circuit along with the ADC and the clutter removal made the video and navigation signals from the display unit become ADC-counted rain data. By comparing the ADC-counted rain data of the Furuno marine radar with the reflectivity obtained by GMR X Band weather radar, it was found that the Furuno rain detection sensitivity only spans from 30-55 dBZ.

Abstract: Aiming at the problem that the traditional tracking method cannot track high speed high maneuvering target effectively, one modified fixed structure multiple model algorithm (M-FSMM) and one modified variable structure multiple model (M-VSMM) algorithm were proposed. The Constant Velocity (CV) model, Current Statistical (CS) and Modified Coordinate Turn (MCT) model were adopted in the M-FSMM algorithm, by means of Connected Graph (CG) thinking, the model connected graph was made up by models that can describe possible motion, the connected relation was set up and model self-adapting was designed to carry out the variable structure tracking that can quickly jump between models. Monte Carlo simulation results show that the two methods can track high speed high maneuvering target effectively, the computational quantum of M-FVMM algorithm is larger but the tracking accuracy and stability are better than the M-FSMM algorithm. They can be used to track near space hypersonic targets.

Abstract: Based on the chirp signal radar using DDS technology, the waveform of the wideband chirp signal source is analyzed. By analyzing the system error model, the method that selecting the chirp steps in accordance with the digits of DDS phase truncation is proposed. It reduces the system errors caused by the phase truncation.

Abstract: The paper presents a synergistic approach for height tracking within a blast furnace (BF). The Frequency Modulated Continuous Wave (FMCW) radar has been employed to measure the height and surface profile of the burden surface. However the radar signal is easily disturbed, by the radar anomalies, during the process of continuous measurement. The data from rotating chute and charging switch provide information on contextual relevance with radar anomalies. An anomaly detection models has been developed to increase the measurement accuracy by utilizing contextual information. The approach has been validated on real BF. The root mean squared (RMS) error in the measured height is reduced by 17% when using the proposed approach compared to the case without it. The results suggest that the proposed approach successfully adapts to changes in the pattern and characteristics of the burden surface.

Abstract: This paper has introduced a kind of method which can simulate the echo signal of radar receiver by the use of the Digital Radio Frequency Memory (DRFM) and Programable Logic Device (PLD).With the realization of actual circuit,the echo simulator can produce intermediate frequency and video signals.Therefore,with the help of the echo simulator, we can raise the detection ability of radar receiver system considerably. The structure of the simulator is simple but its function is great.The echo simulator can simulate intermediate frequency signals of radar receiver system for the first time.So the simulator can locate where isn’t work well of the radar receive system.

Abstract: Pulse compression technology is one of the key technologies in the field of modern radar signal processing, can effectively solve the contradiction between action distance and resolution. In this paper, a radar digital pulse compression system is designed and implemented based on FPGA with linear frequency modulated signal. The digital pulse compression module is designed using FFT IP core which can be reused in different periods of DPC, respectively performing FFT and IFFT calculation, so that the hardware consumption is saved significantly. Therefore, compared with other systems, the system designed in this paper has the characters of fast processing speed, high degree of modularity, real-time processing and short development cycle.

Abstract: In this paper, to solve the problem of measuring angle for broadband single-pulse radar, we proposed the method comparing the magnitude combined with comparing phase to measuring angle which has a more accuracy measurement. It improves the resolution of the radar angle. We analyzed the theoretical effectiveness from the perspective of function. For the amplitude and phase information which used in target angle measurement, we use two-dimensional FFT algorithm to extract them. Simulation results show that this method can accurately measure the angle of radar target.

Abstract: The main principle of radar non - contact life detection technology is the use of electromagnetic wave by the human body, the echo signal is modulated by the surface movement caused the life activities of the human body, so that some parameters of the return signal change. The research on the non contact detection technology, completed the construction of life monitoring system module of hardware, design of software algorithm, real-time data acquisition, and the use of special software algorithms, to detect these changes, and then extracting parameters of human life.