Jong-Soo Ha

Target angle estimation of multifunction radar in search mode using digital beamforming technique

We propose a new target angle estimation method for a multifunction radar in search mode using the digital beamforming technique. The conventional center of mass-based method (CM method) used in mechanical scanning radar or two-dimensional digital beamforming radar is not very useful for a three-dimensional multifunction radar due to many problems. We suggest a three-beam-based angle estimation method (3B method) to reduce the target angle estimation error by the CM method. The 3B method estimates the target angle in search mode with less error than the CM method for all Swerling cases and signal-to-noise ratio.

Design of Simulator for Missile Warning Radar of GVWS

To analyze and verify the performance of a MWR(Missile Warning Radar) of a GVWS(Ground Vehicle Weapon System), there is a need to make a simulator which can conduct the linked and engaged test virtually using the simulated signals. In this paper, a method of the simulator design for MWR is proposed to solve the above need. The SP(Signal Processor) part which generates the simulated signals and analyzes the algorithms is explained. The RF(Radio Frequency) part which transforms IF(Intermediate Frequency) signals into RF signals, radiates RF signals, and controls the linked equipments is also explained. The utility of the proposed design is proved by presenting the results of the contributions to the development of MWR.

Methodology of System Alignment using Angular Error Compensation Among Multi-Axes

ABSTRACT MRDS is a short range missile/rocket defense system which protects a main battle tank(MBT) from threats in a short range. It is composed of 2 radars, 2 infrared trackers(IRTs), 1 fire control computer(FCC), 2 launchers and countermeasures. To guarantee the performance of the MRDS, these components have to be mounted on the vehicle with the known positions and directions and it is required to compensate the alignment errors. In this paper, a system alignment method using angular error compensation is proposed to install its components within a tolerance on the MBT. The test results are presented to evaluate and verify the effectiveness of the proposed method.Key Words : System Alignment(체계정렬), MRDS(미사일/로켓 방어체계) 1. 서 론 능동파괴체계(Hard-Kill System)는 근거리 미사일/로켓 방어체계로서 전차에 탑재되어 위협체를 탐지․추적하고 대응탄을 발사하여 무력화시키는 것을 목적으로 하며, 탐지․추적센서인 탐지추적레이더와 열상추적기(IRT : InfraRed Tracker), 위협판단 및 대응을 통제하는 사격통제컴퓨터, 대응수단인 발사장치와 대응 * Corresponding author, E-mail: jsha@add.re.krCopyright ⓒ The Korea Institute of Military Science and Technology탄으로 구성된다

Performance Analysis of Missile/Rocket Defense System for RPG-7 Defense of Main Battle Tank

ABSTRACT MRDS is a short range missile/rocket defense system which protects a main battle tank(MBT) from threats at a short range. It is composed of 2 radars, 2 infrared trackers(IRT)s, 1 fire control computer(FCC), 2 launchers and countermeasures. In this paper, the radar and the IRT models based on sensing errors, the FCC model based on filtering errors, the launcher model based on driving errors and the countermeasure model based on flying errors are proposed to analyze the defense performance with the approaching RPG-7 and the moving MBT. The simulation results are presented to evaluate and verify the effectiveness of the proposed method.Key Words : Modeling(모델링), Performance Analysis(성능분석), MRDS(미사일/로켓 방어체계) 1. 서 론 능동파괴체계(Hard-Kill System)는 근거리 미사일/로켓 방어체계로서 전차에 탑재되어 위협체를 탐지․추적하고 대응탄을 발사하여 이를 무력화시키는 것을 목적으로 한다. 본 시스템은 위협체를 탐지․추적하는 센서인 탐지추적레이더와 열상추적기(IRT : InfraRed Tracker), 위협판단 및 대응을 통제하는 사격통제컴퓨터, 위협체를 무력화시키는 대응수단인 발사장치와 대 * Corresponding author, E-mail: jsha@add.re.krCopyright

Ultra-wideband imaging radar to reveal obstacles concealed in vegetation to improve navigation of unmanned ground vehicles

To increase mobility of an unmanned ground vehicle (UGV), this study describes the use of forward-looking imaging radar applying ultra-wideband radar technology. If radar is able to visualize images with high resolution in front of a UGV, the radar can be used to support the vehicle by detecting obstacles through foliage. This system employs the multi-input/double-output configuration with two transmitting horn antennas to increase cross-range resolution. Also, two rows of physical receiving antenna arrays provide the height information of targets using an interferometer principle. For visualizing objects in front of the radar, the back-projection method is applied to the data acquired from the receivers. A field test is used to verify the effectiveness of the new radar system. The performance of the radar is proved experimentally by the analysis of image resolution, grass-penetrating capability, and target height information.

A Study on Bistatic SAR Imaging Using Bistatic-to-Monostatic Conversion in Wavenumber Domain

This study describes an omega-K algorithm for focusing bistatic synthetic aperture radar(SAR) data using bistatic-to-monostatic conversion. Bistatic SAR system considered in this study consists of a transmitting antenna and a physical array of several receiving antennas. The length of the physical array is identical to the SAR synthetic aperture. Unlike the monostatic case, an omega-K algorithm for the bistatic case is difficult to obtain the exact equation in the 2D wavenumber domain. The key of the proposed algorithm is converting the bistatic data into a monostatic one. The effectiveness of the proposed algorithm is proved by simulation and real measurement data.

A Study of Bi-Static Through-Wall Imaging Radar Using a Noise Waveform

This paper describes an imaging approach to detect targets behind a wall. To acquire the accurate information over the strong signals reflected by the wall and affected by multipath, a bi-static through-wall imaging radar using a noise waveform is proposed in this paper including the methodology of imaging the received signal. The complete derivation of the proposed approach is presented. And the result of tests is demonstrated to show the possibility of the proposed approach.

A Study on Block Processing Approach for Mono-Static Terrain Imaging Radar

This paper describes a block processing approach to detect targets in front of mono-static terrain imaging radar (TIR). It is difficult to employ several conventional imaging methods of the synthetic aperture radar(SAR) because the TIR is an ultra-wide-band(UWB) type of radar and employs a dechirp-on-receive process. To design an available imaging method, a block processing approach which conducts a range compression and an azimuth compression is proposed in this paper. The complete derivation of the proposed approach is presented. The results of simulations and field tests are demonstrated to show the performance and validity of the proposed approach.

Imaging Method in Time Domain for Bistatic Forward-Looking Radar in Short Range Application

This study describes the time domain imaging algorithm which can be well applied to short-range UWB(ultra wideband) bistatic radar. In the imaging method of SAR technology, the frequency domain method is well applied to the areas which satisfy far-field condition. However in the near-field environment, the image quality is not good due to phase error. However back-projection method based on time domain is well applied to short-range imaging radar. Meanwhile because its processing time is very long, real time-processing is very difficult. To resolve this problem FFBP(Fast Factorized Back-Projection) was proposed. Using the raw data gathered on field we implemented back-projection and FFBP method. Then image quality and processing time were analyzed using these methods.

Method of MBT Movement Modeling for Performance Analysis of SRMD System

SRMD system which protects MBT from the threats in a short range is composed of 2 radars, 2 IRTs 1 CCU and 2 countermeasures. To analyze the performance of this system, there is a need to make the model of MBT on which this system is loaded. In this paper, a method of MBT movement modeling is proposed to fulfill the above need. The methods of the coordinate system transformation among the components and the modeling of a hull`s traveling and a turret`s turning are proposed. The method of the modeling of a pose variation caused by the vibrations is proposed and the results of the modeling are presented.