• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.176-176
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• 2000

Generally, discrete-time processing is applied to the uniformly-sampled signals. But, radars emit pulse trains with irregular time instances. In this paper, we formulate the radar pulse train as a stochastic discrete-time dynamic linear model. The estimation task can be done via linear signal processing using Kalman Filter and some considerations. As a result, we can estimate the pulse repetition interval of a pulse train and predict the time instances of the next pulses to be received.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.99-99
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• 2000

An effect ive filter algorithm that can manage radar beam pointing efficiently is needed to track multi-target in the air. For effective beam management the filter has lobe good enough to predict future position of target and based on this filter output radar beam is control led to point toward the predicted target position in the air. In this paper, we investigate the ${\alpha}$-${\beta}$ filter known for its brief filter structure with the steady-state Kalman filter gain, the ruv filter, and the coordinate-transformed filter that can decouple the measurement noise variance.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.27 no.12
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• pp.1105-1111
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• 2016

In modern warfare, various target tracking radars are used for target location tracking. So, the importance of EA radar jamming technique which disrupt enemy target tracking radar in oder to neutralize tararget location tracking has increased. VGPO/I jamming is a base technique of EA(Electronic Attack), it is possible to operate to pulse-Doppler radar. In this papar, we develop VGPO/I jamming technique that can apply to phase sampled DRFM by using phase information and verifiy through simulations.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.24 no.5
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• pp.574-580
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• 2013

Compared with the TWS(Track While Scan) tracking that uses scan-to-scan correlation at search illuminations for targets track, a phased array radar can use adaptive tracking which assigns additional track illuminations and the track formation range can be improved as a result. In this paper, an adaptive tracking, the search and track illuminations of a target are synchronized such that the extra illuminations are evenly distributed between the search illuminations, is proposed. Markov chain and track formation range for the proposed adaptive tracking are shown with them for the conventional TWS. The simulation result shows that the proposed adaptive tracking has improved track formation range by 27.6 % compared with the conventional TWS tracking under same track confirmation criterion.

• Korean Journal of Remote Sensing
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• v.35 no.1
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• pp.29-37
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• 2019

Synthetic Aperture Radar (SAR) observations are powerful tools to monitor surface's displacement very accurately, induced by earthquake, volcano, ground subsidence, glacier movement, etc. Especially, radar interferometry (InSAR) which utilizes phase information related to distance from sensor to target, can generate displacement map in line-of-sight direction with accuracy of a few cm or mm. Due to decorrelation effect, however, degradation of coherence in the InSAR application often prohibit from construction of differential interferogram. Offset tracking method is an alternative approach to make a two-dimensional displacement map using intensity information instead of the phase. However, there is limitation in that the offset tracking requires very intensive computation power and time. In this paper, efficiency of parallel computing has been investigated using high performance computer for estimation of glacier velocity. Two TanDEM-X SAR observations which were acquired on September 15, 2013 and September 26, 2013 over the Narsap Sermia in Southwestern Greenland were collected. Atotal of 56 of 2.4 GHz Intel Xeon processors(28 physical processors with hyperthreading) by operating with linux environment were utilized. The Gamma software was used for application of offset tracking by adjustment of the number of processors for the OpenMP parallel computing. The processing times of the offset tracking at the 256 by 256 pixels of window patch size at single and 56 cores are; 26,344 sec and 2,055 sec, respectively. It is impressive that the processing time could be reduced significantly about thirteen times (12.81) at the 56 cores usage. However, the parallel computing using all the processors prevent other background operations or functions. Except the offset tracking processing, optimum number of processors need to be evaluated for computing efficiency.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.24 no.3
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• pp.115-121
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• 2024

As the radar mounted on a moving platform moves and rotates, the state of the radar's coordinate system also changes. At this time, in order to track target, the target's coordinates should be converted using the platform state measured from the sensor, and tracking performance may deteriorate due to causes such as sensor noise, communication delay, and sensor update cycle. In this paper, to minimize the degradation of tracking performance because of sensor error, we designed a navigation filter to estimate the state of the moving platform and analyzed the effect of improving tracking performance by applying the navigation filter through a simulation test. To design this navigation filter, three filter algorithms were applied and analyzed to confirm the effect of improving platform position and attitude performance for each filter, and the navigation filter designed by applying the highest performance filter algorithm was applied to a tracking simulation test. Finally we confirmed Improvement in tracking performance before and after applying navigation filters.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.12 no.4
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• pp.263-269
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• 2012

The ability to characterize feature objects from radar readings is often limited by simply looking at their still frame reflectivity, differential reflectivity and differential phase data. In many cases, time-series study of these objects' reflectivity profile is required to properly characterize features objects of interest. This paper introduces a novel technique to automatically track multiple 3D radar structures in C,S-band in real-time using Doppler radar and profile their characteristic reflectivity distribution in time series. The extraction of reflectivity profile from different radar cluster structures is done in three stages: 1. static frame (zone-linkage) clustering, 2. dynamic frame (evolution-linkage) clustering and 3. characterization of clusters through time series profile of reflectivity distribution. The two clustering schemes proposed here are applied on composite multi-layers CAPPI (Constant Altitude Plan Position Indicator) radar data which covers altitude range of 0.25 to 10 km and an area spanning over hundreds of thousands $km^2$. Discrete numerical simulations show the validity of the proposed technique and that fast and accurate profiling of time series reflectivity distribution for deformable 3D radar structures is achievable.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.44 no.3
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• pp.22-28
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• 2007

The STIR(Signal Tracking & Illumination Radar) in KDX(Korean Destroyer Experimental) combat system acquires target from designating 3-D target information of surveillance radar (MW-08), and The performance of radar is decided by target acquisition time and accuracy of tracking loop because the STIR tracks automatically in accordance with tracking algorithm. In the view of ship, elements related with target acquisition time of the STIR can be various. In this paper the target acquisition time of the STIR is reduced by identifying the elements and suggesting the performance improvement method. The way of performance improvement is suggested through analysing main affecting factors. First, tracking algorism is required for analysis. Second, fitness of parameters that control elements related with acquisition distance is analyzed. And the third, accuracy of ship based sensors is analyzed. In conclusion, acquisition time against ship target can be advanced to 3 seconds from 10 seconds.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.23 no.2
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• pp.51-59
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• 2023

The tracking radar system is installed and operated on the ground, ships, and aircraft, and requires a design to withstand electromagnetic interference with nearby electronic devices. In this case, radiation and immunity standards for cable connection must be satisfied to prevent malfunction of other equipment due to electromagnetic wave interference caused by cables connected to the tracking radar. The radiation standard must also be satisfied so that the electromagnetic wave noise generated and radiated from the tracking radar does not affect the peripheral device, so that the immunity standard for the electromagnetic wave emitted from the peripheral device must be satisfied. In this paper, we propose a design to satisfy MIL-STD-461G including CE, CS, RE, and RS, and explain design satisfaction through tests.

• Journal of the Korea Institute of Military Science and Technology
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• v.13 no.4
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• pp.569-576
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• 2010

Jamming simulator has developed for the purpose of the test and evaluation on the electronic protection capabilities of the tracking radar onboard ship. This simulator has the capabilities to generate and radiate the jamming signals against the radar as well as those to receive, analyze and identify the radar signals at a real sea environment. The limited space of ship superstructure has led to the serious distortion caused by the ring around phenomenon that some sidelobes of the jamming beams were coming back to the receiving antenna. In this paper, we have proposed the methods to eliminate the ring around. First, we have inserted the groove metal screen between transmitting and receiving antennas. Second, we have used the PRI(Pulse Repetition Interval) tracking loop to control the switching timing of the input radar and the output jamming signal. Finally, we have demonstrated the performance and effectiveness of the proposed methods through the sea trial.