• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2004.07a
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• pp.317-317
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• 2004

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2004.07a
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• pp.310-310
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• 2004

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.2
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• pp.164-169
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• 2010

Since the range and Doppler resolution of the synthetic aperture radar(SAR) image becomes very high, the target detection accuracy can be significantly increased, but the computational burden is also increased. The conventional single-cell based CFAR detector performs the target detection on every single cell basis, thus it causes the serious increment of the computational load. In this paper, the improved two-step MCA-CFAR detector is proposed for the improvement of the target detection as well as the reduction of computational load: the first step is to use the MCA-CFAR, and the second step is to use the single-cell based CFAR detection in the expected target area for final decision. The performance of the proposed algorithm is compared with the conventional single-cell based CFAR and MCA-CFAR on SAR images.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.40 no.5
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• pp.333-340
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• 2003

Doppler processing is the heart of pulsed Doppler radar. It gives a clutter elimination and coherent integration. With the improvement of digital signal processors (DPSs), the implementation using them is more widely used in radar systems. Generally, so as for Doppler processor to process the input data in real time, a parallel processing concept using multiple DSPs should be used. This paper implements a programmable Doppler processor, which consists of MTI filter, DFB and square-law detector, using 8 ADSP21060s. Formulating the distribution time of the input data, the transfer time of the output data and the time required to compute each algorithm, it estimates total processing time and the number of required DSP. Finally, using the TSG that provides radar control pulses and simulated target signals, performances of the implemented Doppler processor are evaluated.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.12
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• pp.1762-1764
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• 2016

A pulse radar signal is characterized by periodic pulses and noise components between them. In this Letter, we present a test statistic for detecting the presence of a pulse radar which exploits the inherent characteristics of a pulse radar signal by the ratio of maximum power to minimum power from the received signal and compares its sensing performance with that of the energy detector by computer simulation in a variety of situations.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10a
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• pp.541-547
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• 1992

The phased array antenna has the ability to perform adaptive sampling by directing the radar beam without inertia in any direction. The adaptive sampling capability of the phased array antenna allows each sampling time interval to be varied for each target, depending on the acceleration of each target at any time. In this paper we design a three-dimensional adaptive tracking algorithm for the phased array radar system with a given set of measurement parameters. The tracking algorithm avoids taking unnecessarily frequent samples, while keeping the angular prediction error within a fraction of antenna beamwidth so that the probability of detection will not be degraded during a track update illuminations. In our algorithm, the target model and the sampling rate are selected depending on the target range and the target maneuver status which is determined by a maneuver detector. A detailed simulation is conducted to test the validity of our tracking algorithm for encounter geometries under various conditions of maneuver.

• Proceedings of the KSME Conference
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• 2001.11a
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• pp.32-37
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• 2001

As increasing underground facilities, more effective management is needed nowadays. It is important to get an accurate information of underground facilities to manage that, so some methods of detecting location - electromagnetic induction method, ground penetration radar method, sonic method - are used to obtain the information of underground facilities. In this study, a magnetic method to detect underground facilities was developed. In the magnetic method, underground facilities are detected by a detector and the magnetic marker which is a permanent magnet and used to marking the location by attaching underground facilities. A proper characteristic of the magnetic marker was optimized by maxwell 20 magnetic field analysis tool, a test field was constructed with the magnetic marker, PVC pipe, and steel pipe under ground 1.5m, and the detector was made by modifying a common ferromagnetic detector. Magnetic strengths of the magnetic marker were measured by the detector at each location in the test field, and analyzed by magnetic field analysis tool in the same condition. In the result, the underground pipes were detectable within the deviation ${\pm}20cm$ at PVC pipe and ${\pm}10cm$ at steel pipe respectively. The steel pipe was more detectable by ferromagnetism. The developed magnetic method can be applied to maintain and manage underground facilities.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.9
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• pp.63-69
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• 2003

As increasing underground facilities, more effective management is needed nowadays. It is important to get an accurate information of underground facilities to manage that, so some methods of detecting location - electromagnetic induction method, ground penetration radar method, sound wave method - are used to obtain the information of underground facilities. In this study, a magnetic method to detect underground facilities was developed. In the magnetic method, underground facilities are detected by a detector and the magnetic marker which is a permanent magnet and used to marking the location by attaching underground facilities. A test field was constructed for experiment with the magnetic marker, PVC pipe, and steel pipe under ground 1.5m, and a ferromagnetic detector was used for measurement. Magnetic strengths of the magnetic marker were measured by the detector at each location in the test field, and analyzed by magnetic field analysis tool in the same condition. In the result, the underground pipes of 1.5m below were detectable within the deviation $\pm$0.2m. When For applying this method, it should be considered that ferromagnetic materials around the detector could affect a measured value.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.8
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• pp.1346-1354
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• 2000

본 논문에서는 기존의 루프감지기와 호환성이 있는 레이더 기술을 이용한 차량감지기를 개발하였다. 24 ㎓의 FMCW 고도계와 도플러 속도계 기술을 이용하여 도로상의 차량 길이와 속도정보를 알아낼 수 있는 비매설형의 차량감지기이다. 신호처리에는 DAQ 보드를 사용하였고, 응용소프트웨어인 LabView로 프로그래밍 하였다. 기존의 루프 감지기와 연결된 교통정보 네트웍과의 호환성을 위해 RS-232C 표준인터페이스를 이용하여 VDS(Vehicle Detector System)로 차량데이터를 전송하였다. 속도와 차량길이 정보의 정확도에 있어서 기존 루프감지기보다 약 10% 정도 향상되었음이 측정되었다.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.15 no.11
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• pp.1075-1081
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• 2004

In this paper, a VCO of a general advance warning system for vehicle's speed limitation in the X-band used in Japan is designed using a small signal scattering coefficient of PHEMT. A varactor diode that wide tuning range and series resistance 0 H is used for designing the VCO and -85 dBc/Hz of phase noise at 10 kHz of offset frequency is obtained by adjusting the reflection coefficient between the micro-strip line and the varactor device which determines transistor's operation voltage and resonant frequency, In addition +4.5 dBm of basic frequency signal output level and -25.6 dEc of the second harmonic constraint are acquired. Sample that produce in this paper could confirm that more excellent special quality appears than existing products in sensitivity.