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Recently, as the market for SMART TV expands, the camera is embedded for providing various user experience. However, this leads to occurrence of camera failure due to TV power up sequence problem, which are usually not detectable in conventional test equipments. Although the failure-detection can be possible by re-generating control signals for audio interface with new equipment, it is expensive and also requires much time to test. In this paper, for SMART TV, FPGA(Field Programmable Gate Array)-based failure-detection system is proposed which can lead to reduction of both cost and time for test.

This paper presents the signal-to-interference plus noise ratio (SINR) estimation of IEEE 802.16m WirelessMAN-Advanced mobile station with simulation and implementation results. The downlink signal of IEEE 802.16m has two kinds of A-Preambles: the PA-preamble and the SA-preamble. This paper proposes the efficient method of estimating SINR with A-Preambles, by measuring noise power from PA-preamble and measuring interference power and signal power from SA-preamble. The proposed SINR measurement block contains important features such as subcarrier phase rotation elimination and simplified dB transform. The result of this paper is integrated to ETRI's IEEE 802.16m test mobile station, used for decision of adaptive-modulation-and-coding (AMC) and hand-over. It showed good measurement performance in simulation and unified system link test also.

A passive infrared or pyroelectric infrared (PIR) sensor is mainly used to sense the existence of moving objects in an indoor environment. However, in an outdoor environment, there are often outbreaks of false alarms from environmental changes and other sources. Therefore, it is difficult to provide reliable detection outdoors. In this paper, two algorithms are proposed to reduce false alarms and provide trustworthy quality to surveillance systems. We gather PIR signals outdoors, analyze the collected data, and extract the target features defined as window energy and alarm duration. Using these features, we model target and false alarms, from which we propose two target decision algorithms: window energy detection and alarm duration detection. Simulation results using real PIR signals show the performance of the proposed algorithms.

As broadcasting environments change rapidly to digital, user requirements for next-generation broadcasting service which surpass current HDTV service become bigger and bigger. The next-generation broadcasting service progress from 2D to 3D, from HD to UHD and from 5.1ch audio to more than 10ch audio for high quality realistic broadcasting service. In this paper, we propose 10.2ch based multichannel audio reproduction system for UHDTV. The 10.2ch-based audio reproduction system add two side loudspeakers to enhance the surround sound localization effect and add two height and one ceiling loudspeakers to enhance the elevation localization effect. To evaluate the proposed system, we used APM(Auditory Process Model) for objective localization test and conducted subjective localization test. As a result of objective/subjective localization test, the proposed system shows the statistically same performance compare with 22.2ch audio system and shows the significantly better performance compared with 5.1ch audio system.

In this paper, a new frequency offset estimation method in OFDM system is suggested. To measure fractional part of frequency offset, the repetition feature of cyclic prefix and that of training sequence is adopted. Both method shows relatively large frequency offset estimation error under low SNR circumstances, but this error can be greatly reduced by joint measurement of cyclic prefix and inversely repeated training symbol such as primary advanced preamble (PA-preamble) of IEEE 802.16m IMT-Advanced WiMax system. In this paper, the performance of suggested frequency offset estimation method is verified in IEEE 802.16m IMT Advanced WiMax system, using its PA-preamble and cyclic prefixes of A-preambles.

A bistatic radar using the pulse chasing can detect a target to track successive transmitted pulses using a receive beam for effectively scanning the cosite search area. When tracking a transmitted pulse with the receive beam, some beam pointing errors within pulse-to-pulse can cause the timing error in received pulse and the variation of the signal strength. In this paper, we have proposed that some errors due to the receive beam pointing error could limit the MTI filter`s performance and derived that the relationship between the MTI performance and the geometric factors which are the inherent properties in bistatic configuration. Through the simulation, we have considered the limitations of the improvement performance restricted by the receiving beam pointing error and confirmed the contribution to the performance improvement in maintaining the receiving beam pointing error of under 0.5 degrees.

It is rather difficult to improve flight control computer(FLCC) hardware(H/W) development schedule due to lack of commercial off-the-self(COTS) tools or target specific tools. Thus, it is suggested to develop an enhanced process utilizing modeling, simulation and virtual reality tools. This paper presents H/W design process enhancement tool(PET) for FLCC design requirements such as FLCC input/output(I/O) signal flow, I/O fault detection, failure management algorithm, circuit logic, PCB assembly configuration and installation utilizing simulation and visualization in virtual space. New tool will provide simulation capability of various FLCC design configuration including shop replaceable unit(SRU) level assembly/dis-assembly utilizing open flight format 3-D modeling data

The KO-1 aircraft which has the functionality of tactical observation, was successfully developed in August of 2004 in South Korea. It is important for the KO-1 aircraft to achieve successful missions at nighttime as well as during daytime. The aircraft, equipped with interior and exterior lighting systems and lighting control panel modified from those of the KT-1 basic trainer, provides improved safety, operational effectiveness, and situational awareness during operation at night when used with night-vision goggles (NVGs). KO-1 is the first domestic aircraft that utilizes the night-vision imaging system (NVIS) technology in Korea. KO-1 NVIS was developed with the goal of defining the components of NVIS and establishing test and evaluation procedures for both the subsystems and main system. In this paper, we present the establishment of a KO-1 NVIS lighting system, NVIS component development, and representative ground and flight test results.

This paper presents architecture of the PTN-OTN integrated switch fabric module which supports 3.2 terabit switching capabilities in optical-circuit-packet converged transport network systems. The switch fabric module supports not only PTN-OTN converged switching function between integrated line cards that support PTN and OTN traffics, but also provides system timing synchronization function to each line cards and mate switch fabric cards.

Monitoring abnormalities within reactor coolant pumps due to vibration, we introduce a Wigner distribution (WD) to a vibration monitoring system for analyzing vibration signals, and develop an on-line diagnostic method using the neural network employing back propagation algorithm. A rotor kit is used to simulate the abnormal conditions in the pump such as bearing rubbing, shaft bending, misalignment, etc. The data collected from the kit are analyzed using both a conventional system based on the Fourier transform (FT) and the software developed with the WD in this study, and they are compared. The study shows that spectrum represented by WD makes it easy to analyze the vibration signals of a rotating machine and the developed diagnostic method will help the operators grasp the cause of vibrations.

If small cracks in stud bolts are not detected early enough, they can grow rapidly and cause catastrophic disasters in industrial facilities such as nuclear power plants. Their detection, despite its importance, is known to be a very difficult problem due to the complicated structures of the stud bolts. This study shows a method of detecting the existence and determining the size of a small crack in a root between two crests in the bolt threads using ultrasound. The Rayleigh wave propagating from the tip of a crack to the opening of the same crack is utilized. A delayed pulse, due to the Rayleigh wave, is detected between regularly spaced pulses from the threads, with the delay time being proportional to the size of the crack. Theoretical explanation is presented and experimental results demonstrating detection of cracks as small as 0.5 mm are shown.

GPON Extender is required to extend transmission reach in GPON. In this paper, we propose simple activation techniques and a burst reset controller for the extender, and discuss experimental results of the Extender with CWDM links.

Bolt degradation has become a major issue in the nuclear industry since the 1980's. If small cracks in stud bolts are not detected early enough, they grow rapidly and cause catastrophic disasters. Their detection, despite its importance, is known to be a very difficult problem due to the complicated structures of the stud bolts. This paper presents a method of detecting and sizing a small crack in the root between two adjacent crests in threads. The key idea is from the fact that the mode-converted Rayleigh wave travels slowly down the face of the crack and turns from the intersection of the crack and the root of thread to the transducer. Thus, when a crack exists, a small delayed pulse due to the Rayleigh wave is detected between large regularly spaced pulses from the thread. The delay time is the same as the propagation delay time of the slow Rayleigh wave and is proportional to the site of the crack. To efficiently detect the slow Rayleigh wave, three methods based on digital signal processing are proposed: wave shaping, dynamic predictive deconvolution, and dynamic predictive deconvolution combined with wave shaping.

This paper proposes an improved power control method, changing the target bit energy per noise spectral density (Eb/No) threshold with adaptive up and down step sizes in variable fading environments. We carry out computer simulations and hardware experiments for verification of the method. The new method results in better frame error rate (FER) and Eb/No performance than the existing ones.

This paper describes an analysis of repeater effects in a CDMA system. The use of repeaters is very cost-effective when the service providers want to overcome coverage holes and enlarge the coverage area. But the repeater acts as a new source of interference to the neighboring cells. It may have an influence on wireless networks and could result in lowering of quality. Therefore this paper analyzes the effect on wireless networks by a repeater in positive and negative aspect.

In an uplink cable modem, it is crucial to employ a preamble pattern suitable for frame acquisition, channel estimation and coarse timing/frequency acquisition. Proposed is an oversampled constant envelope zero autocorrelation code (CAZAC) for an uplink cable modem compliant with the data over cable service interface specification. The false alarm and missing probability of the proposed preamble pattern are investigated and compared to those of the existing preamble pattern based on the extended CAZAC sequence.