The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
The polarization state of the radar antenna is slow changed, which makes the radar can estimate the polarization parameters of the signal. This paper presents a new method based on the observation equation by least squares method, considering the radar observation equation of antenna polarization matrix is built in the complex domain, we puts forward a transformation method to realize real coefficient...
The results on the use of arbitrary waveform generators that are based on FPGA technology for generation of complex signals in modern noise radars are presented. On the basis of these devices we propose a radar scheme with digital generation of noise waveforms for both sounding signal and reference and analog processing. Experimental results show efficiency of FPGA-based application in radar with...
In this paper, we proposed a new algorithm to improve the image quality degradation due to sparse array topology and small fractional bandwidth of commercial radar chip in two-dimensional (2-D) multiple-input-multiple-output (MIMO) impulse radio ultra-wideband (IR-UWB) array imaging system. The new algorithm, which adds a clustering concept and signal windowing method to the existing delay-and-sum...
The feasibility of Forward Scatter Radar (FSR) that exploits pulsars as transmission sources for the purpose of air targets detection is examined. We theoretically calculated the power budget for air target detection using such a FSR system with the higher-gain radio telescopes used as receivers. The numerical results are obtained for three known radio telescopes and three pulsars.
Frequency-Modulated Continuous-Wave Synthetic Aperture Radar (FMCW SAR) is a compact, cost-effective and high-resolution remote sensing system. The Frequency non-linearities of FMCW SAR seriously deteriorate its range resolution. To overcome this problem and integrate the non-linearity correction method into the imaging algorithm, in this paper, we propose a non-linear range-Doppler algorithm for...
Synthetic aperture radar tomography, or volume imaging with a side-looking radar uses a two-dimensional aperture made of several antenna paths along more or less parallel trajectories. The carrier motion providing the along track extension of the aperture, and the across-track extension is provided by multiple cross-track antenna or by repeated acquisition along parallel lines. The relative position...
SAR is a very popular instrument for imaging of the ground surface. Possibility of high-resolution image formation makes it superior tool for various information extraction tasks. In the paper, a problem of automatic target recognition is comprehensively analyzed. An idea of azimuth and range target profiles fusion is proposed. It is demonstrated, that usage of a proper image preprocessing with appropriate...
The article presents an experimental sonar high resolution imaging system capable of producing three-dimensional images of observed objects. The system works in an inverse synthetic aperture configuration with rotating object. In order to achieve a 3-D image the vertical position of the sensor changes during the observation. The architecture of the ultrasonic sensor, simulation as well as experimental...
The paper addresses a problem of ballistic object trajectory estimation on the basis of measurements from a cinetheodolite electro-optical tracking system. The object flight dynamics is modeled using a three degrees of freedom equations of motion. The estimation of object trajectory is performed with the use of an Extended Kalman Filter.
In this paper, we conduct an experimental study with the aim to obtain a large number of estimates of various parameters characterizing the GPS shadows created by three types of moving vehicles. The experimental cars have a similar size and therefore, the obtained estimates have similar values. From the results, it can be seen that the cars can be differentiated by means of their shadow parameters.
Overlapped subarrays have cost benefits compare to non-overlapped subarrays. The main cost of phased array radars are for phase shifter or true time delay modules in the case of wide band radars. In overlapped approach, each phase shifter (or time delay module) might have more than one output and it would reduce costs. Although, overlapped subarrays could fit in reduced space too. A main problem in...
In this paper we present a series of road scene images recorded with a prototype high resolution low-THz imaging radar. The aim of this study is to assess the images in order to identify and extract features of interest for scene characterisation to aid the development of future autonomous vehicles. Images were recorded at multiple radar heights in order to assess the effect of illumination angle...
A new method for generation of binary pseudorandom sequences (BPR-sequences) with quasi-perfect periodic and inverse periodic autocorrelation has been suggested for applications in radars. The method is based upon a modified discrete multi-dimensional chaotic map with two delays. Various BPR-sequences generated according to the method suggested has been analyzed using computer simulation. Spectrums...
This paper studies the impacts of ionospheric scintillation on geosynchronous SAR (GEO SAR). A phase screen model is used to simulate the influence of ionospheric scintillation on GEO SAR. In this model, the ionospheric scintillation status (i.e. the thin phase screen) is generated by employing the Rino equation and the climatological paramters (such as CkL, p and L0). When wave passes through the...
This paper focuses on the estimation of target's motion parameters in a moving transmitter/moving receiver forward scatter radar scenario. An extension of the quasicoherent processing initially developed for stationary FSR mode of operation is introduced. This offers an estimation of the target's trajectory in a general case where transmitter and receiver can be moving. Simulated and real data are...
Monopulse is a widely used algorithm to estimate the target angular co-ordinates in radar application. Formulas exist that give approximate values for the accuracy achievable with monopulse. This paper derives simple but accurate closed formulas to estimate the monopulse accuracy by taking into account the radar detection threshold (and then PD and Pfa) and the target fluctuation models.
In a Multi-Function Radar (MFR), the radar surveillance plays a critical role to optimize the radar performance. The surveillance usually takes more time than other functions. In this paper, we use the Adapt_MFR, an MFR radar simulator, to analyze the benefits of target prioritization. By simulation of a multiple target scenario, we try to find out both the benefits and disadvantages of prioritization...
One of the most fundamental tasks in autonomous driving is the recognition of the road ahead. Using radar data, this is usually done via rule based algorithms. This paper proposes a deep learning approach to estimate the course of the ego lane based on occupancy grids generated by radar sensors. The method is also able to simultaneously give a reliability measurement of the predicted driving path...
This paper tests and demonstrates the ability of a twin set of passive radar systems to monitor real time an area of interest and track medium size targets. The results are based on a real data acquisition campaign performed using two eleven element array antenna based passive radars in the Oslo fjord area in September 2016.
Purpose of the paper is to present a solution for the target height estimation problem for multi-frequency multi-static passive radar. Aim of the proposed estimation strategy is to provide 2D passive sensors, which measure only bistatic range and Doppler, with target height estimation capability via the simultaneous exploitation of multiple FM transmitters (88–108 MHz). Results achieved with simulated...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.