• Journal of Positioning, Navigation, and Timing
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• v.7 no.3
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• pp.113-125
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• 2018

Since the global positioning system receivers on the surface of the Earth use satellite signals sent from a remote distance and the intensity of received signals is weak, they are vulnerable to jamming. This paper implements a vector-tracking loop (VTL)-based global navigation satellite system (GNSS) receiver algorithm as an anti-jamming technique and compares the performance of VTL-based receivers with that of scalar-tracking loop (STL) that is used in general GNSS receivers at various jamming environments and a vehicle's dynamics. The simulation results shows that VTL is more robust against jamming than STL in all operating environments.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.16 no.3 s.94
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• pp.293-299
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• 2005

This paper introduces a program by which one can perform measurement, analysis, and simulation of electro-magnetic environment which affects on vehicular AV receivers. An integrated system of EM environment collected, GPS(Global Positioning System) informations, and developed simulation program can be an important evaluating tool for the analysis of automobile AV receivers.

• 한국태양에너지학회:학술대회논문집
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• 2012.03a
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• pp.280-285
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• 2012

It is important to produce the high temperature and high pressure air for the concentrated solar power system using the combined cycle. In this paper, based on the concept of tubular receiver, we designed two types with focus on radiation loss reduction. These two receivers were tested in the KIER solar furnace of 40kW thermal capacity. Performance of the two receivers were evaluated and compared.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2011.11a
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• pp.78-81
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• 2011

In this paper, we propose an additional data transmission scheme using multiple-antennas with backward compatibility for legacy ATSC (Advanced Television Systems Committee) terrestrial DTV (digital television) receivers. The proposed scheme improves the data rate and bit error rate performance compared to the conventional single antenna transmission scheme for additional data. Also, the proposed scheme guarantees backward compatibility for legacy ATSC DTV receivers.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2011.11a
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• pp.247-250
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• 2011

In this paper, we propose an additional data transmission scheme using multiple-antennas with backward compatibility for legacy ATSC (Advanced Television Systems Committee) terrestrial DTV (digital television) receivers. The proposed scheme improves the data rate and bit error rate performance compared to the conventional single antenna transmission scheme for additional data. Also, the proposed scheme guarantees backward compatibility for legacy ATSC DTV receivers.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.04a
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• pp.537-543
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• 1997

A new procedure for the advanced one-side measurement of longitudinal wave and surface wave velocities in concrete is presented in this paper. Stress waves are generated in a consistent fashion with a DC solenoid. Two piezoelectric accelerometers are mounted on the surface of a specimen as receivers. Stress waves propagate along the surface of the specimen and are detected by the receivers. In order to reduce the large incoherent noise levels of the signals, signals are collected and manipulated by a computer program for each velocity measurement. For a known distance between the two receivers and using the measured flight times, the velocities of the longitudinal wave and the surface wave are measured. The velocities of the longitudinal wave determined by this method are compared with those measured by conventional methods on concrete, PMMA and steel.

• Solar Energy
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• v.20 no.3
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• pp.61-73
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• 2000

Heat losses from receivers for a dish-type solar energy collecting system are numerically investigated. The analytical method for predicting conductive heat loss from a cavity receiver is used. The Stine and McDonald Model is used to estimate convective heat loss. Two kinds of techniques for the radiation analysis are used. The Net Radiation Method that is based on the radiation heat balance on the surface is used to calculate the radiation heat transfer rate from the inside surface of the cavity receiver to the environment. The Monte-Carlo Method that is the statistical approach is adopted to predict the radiation heat transfer rate from the reflector to the receiver. Based on the heat loss analysis, the performance of two different receivers for multifaceted parabolic solar collectors with several flat facets can be estimated, and the optimal facet size is obtained.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.3
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• pp.539-546
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• 1997

In this paper, we proposed a new mehtod to analyze the performance degradation by timing jitters in the APD (avalanche photodiode) receivers of intensity modulation/direct detection digital optical communication systems where raised cosine pulse-shaping filters are used to reduce the effect of noise while minimizing intersymbol interferences. The proposed analytical method is an extension of an analytical method we have already developed for pin diode receivers, and incorporates the effects of APD's multiplication factor and resulting shot noise. Using the proposed analytical method, we derive an approximated power penalty due to timing jitters based on an assumption of Gaussian distribution for timing jitters, and compare with that of the conventional analytical method. The results obtained from the proposed analytical method show that conventional analytical methods underestimate the influence of timing jitters on the reciver performance. The results also show that APD's multiplication factor which optimizes receiver sensitivity is smaller than that obtained by the conventional analytical method.

• Journal of the Korean Institute of Navigation
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• v.23 no.4
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• pp.89-96
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• 1999

This paper is concerned with the experimental analysis of EOW(End-of-Week) rollover. The GPS EOW Rollover happens every 20 years. Because GPS time, counted in weeks, started counting Jan. 6, 1980, the GPS week will rollover from week 1023 to 0000 at midnight between Aug. 21 and 22. This is significant because it is the first EOW rollover since the GPS constellation was established and it could be interpreted as an invalid date in receivers that were not designed to meet GPS specification. We analyzed GPS data of the noncompliant receivers and the compliant receiver. It was concluded that all receivers had not serious problems during or after the rollover.

• 한국정보통신설비학회:학술대회논문집
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• 2008.08a
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• pp.253-256
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• 2008

In this paper, we analyze the performance of RAKE receiver for impulse radio-ultra wide band (IR-UWB) systems in indoor multipath radio channel. Pulse position modulation-time hopping (PPM-TH) signal is considered. And we also consider three types of RAKE receivers, which are ideal RAKE, selective RAKE, and partial RAKE receivers. The indoor channel is modeled as the modified Saleh and Valenzuela (SV) model which has been proposed as a UWB channel model by the IEEE group, IEEE 802.15.SG3a.