• ETRI Journal
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• 제29권1호
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• pp.110-112
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• 2007

As an alternative to the classic linear detector which only assumes noise variance, a new robust detector with noise variance estimation censoring input signals over AWGN is proposed. The results demonstrate that analytic detection probability matches the simulation results for the linear detector and that the new robust detector shows better performance than the linear detector when the number of samples increases.

• Communications for Statistical Applications and Methods
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• 제19권4호
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• pp.579-590
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• 2012

Local linear jump detection in a discontinuous regression function involves the choice of the bandwidth and the performance of a local linear jump detector depends heavily on the choice of the bandwidth. However, little attention has been paid to this important issue. In this paper we propose two fully data adaptive bandwidth selection methods for a local linear jump detector. The performance of the proposed methods are investigated through a simulation study.

• Journal of Communications and Networks
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• 제16권5호
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• pp.485-492
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• 2014

Spectrum sensing for cognitive-radio applications may use a matched-filter detector (in the presence of full knowledge of the signal that may be transmitted by the primary user) or an energy detector (when that knowledge is missing). An intermediate situation occurs when the primary signal is imperfectly known, in which case we advocate the use of a linear-quadratic detector. We show how this detector can be designed by maximizing its deflection, and, using moment-bound theory, we examine its robustness to the variations of the actual probability distribution of the inaccurately known primary signal.

• 전자공학회논문지A
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• 제33A권5호
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• pp.1-9
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• 1996

In this paper, we propose an efficient computational algorithm that can reduce significantly the computational complexity of the ML optimum multiuser detector known as the most excellent detector in synchronous code division multiple access channels. The proposed detector uses the sequential detection algorithm based on the alternating maximization appraoch to obtain the ML estimates. As initial estimates for this sequential algorithm, we can use the estimated values obtained by the conventional single-user detector, the linear decorrelating multiuser detector, or the decorrelating decision-feedback muliuser detector, the linear decorrelating multiuser detector, or the decorrelating decision-feedback multiuser detector. We have performed computer simulations in order to see the convergence behaviors and the detection performance of the propsoed algorithm in terms of initial algorithms and the number of users, and then to compare the computational complexity with that of the ML optimum multiuser detector. From the results, we have seen that the proposed alternating maximization detector has nearly equal detction performance with that of the ML optimum multiuser detctor in only a few iteration.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1998년도 하계종합학술대회논문집
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• pp.106-109
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• 1998

Wireless communication systems, in particular, must operate in a crowded electro-magnetic environmnet where in-band undesired signals are treated as noise by the receiver. These interfering signals are often random but not Gaussian Due to nongaussian noise, the distribution of the observables cannot be specified by a finite set of parameters; instead r-dimensioal sample space (pure noise samples) is equiprobably partitioned into a finite number of disjointed regions using quantiles and a vector quantizer based on training samples. If we assume that the detected symbols are correct, then we can observe the pure noise samples during the training and transmitting mode. The algorithm proposed is based on a piecewise approximation to a regression function based on quantities and conditional partition moments which are estimated by a RMSA (Robbins-Monro Stochastic Approximation) algorithm. In this paper, we develop a diversity combiner with modified detector, called Non-Linear Detector, and the receiver has a differential phase detector in each diversity branch and at the combiner each detector output is proportional to the second power of the envelope of branches. Monte-Carlo simulations were used as means of generating the system performance.

• 한국컴퓨터정보학회논문지
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• 제22권10호
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• pp.19-26
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• 2017

In this paper, we propose an efficient image equipment implementation for the detector characteristics of various detectors by analyzing un-cooled thermal detector that exhibits nonlinear changes due to external temperature effects. First, we explain Thermal Electric Cooler for un-cooled detector temperature control system and Non-image correction methode for IR system. Second, we present the results of a study on an efficient control technique that can minimize the deterioration of image quality by controlling a un-cooled thermal detector without a thermal electric cooler(TEC) inside. Third, we suggest Image Correction Methods for Uncooled IR TECless Detector with Non-linear characteristics due to Temperature Change. So, we analyze and present the results of Image correction methods for various un-cooled thermal detector.

• Bulletin of the Korean Chemical Society
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• 제14권2호
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• pp.211-215
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• 1993

A multichannel optical detector system employing a self-scanning linear photodiode array has been developed. The photodiode array detector system is designed for various applications which require fast, multichannel detection of transient signals. The detector system consists of a controller which runs on an IBM personal computer and a detector head connected to the controller through a DB-15 cable. The entire scanning of 1024 detector elements is achieved in 20 ms. By using an on-board 16-bit counter/timer, the operational mode of the photodiode array detector is fully programmable by software. The design considerations and the performance of the photodiode array detector system is presented.

• 전자공학회논문지
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• 제51권1호
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• pp.97-103
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• 2014

본 논문에서는 1/8-rate 위상검출기를 이용한 클록-데이터 복원회로를 제안한다. 기존의 full-rate 또는 half-rate 위상검출기의 사용은 동일 데이터 속도에서 복원된 클록의 주파수가 상대적으로 높아야 하므로 샘플링회로와 VCO의 설계에 부담으로 작용한다. 본 논문에서는 복원된 클록의 주파수를 낮추기 위해 1/8-rate 클록을 사용할 수 있는 위상검출기를 구성하고 Linear equalizer를 위상검출기 입력에 사용하여 복원된 클록의 지터를 감소시켰다. 테스트 칩은 0.13-${\mu}m$ CMOS 공정으로 제작되었고 입력은 3-Gb/s PRBS 데이터 패턴, 동작전압은 1.2-V에서 측정되었다.

• 한국측량학회지
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• 제39권5호
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• pp.253-263
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• 2021

Traffic data collected using advanced equipment are highly valuable for traffic planning and efficient road operation. However, there is a problem regarding the reliability of the analysis results due to equipment defects, errors in the data aggregation process, and missing data. Unlike other detectors installed for each vehicle lane, radar detectors can yield different error types because they detect all traffic volume in multilane two-way roads via a single installation external to the roadway. For the traffic data of a radar detector to be representative of reliable data, the error factors of the radar detector must be analyzed. This study presents a field survey of variables that may cause errors in traffic volume collection by targeting the points where radar detectors are installed. Video traffic data are used to determine the errors in traffic measured by a radar detector. This study establishes three types of radar detector traffic errors, i.e., artificial, mechanical, and complex errors. Among these types, it is difficult to determine the cause of the errors due to several complex factors. To solve this problem, this study developed a radar detector traffic volume error analysis model using a multiple linear regression model. The results indicate that the characteristics of the detector, road facilities, geometry, and other traffic environment factors affect errors in traffic volume detection.

• 한국통신학회논문지
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• 제33권9A호
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• pp.917-923
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• 2008

D-STTD 시스템은 Alamouti Code로 알려진 STTD기법을 적용하여 다이버시티 효과를 획득하면서 STTD기법을 병렬로 한번 더 사용함으로써 멀티플렉싱 효과도 얻을 수 있는 기법이다. 이러한 서로 다른 정보를 보내는 멀티플렉싱 효과로 인해 D-STTD는 기존 STTD 기법의 Combining 기법을 적용하는데 어려움을 가져온다. 그래서 본 논문에서는 MMSE 기법을 바탕으로 멀티플렉싱 검출 기법으로 잘 알려진 Linear 알고리즘, SIC 알고리즘, OSIC 알고리즘을 D-STTD 시스템에 적용하고 그 성능을 비교한다. 그리고 새롭게 MAP 알고리즘을 D-STTD 시스템에 적용하여 성능을 분석하고자 한다. 모의 실험 결과, Linear MMSE Detector보다 반복 알고리즘을 적용한 Detector가 최대 3.7dB의 성능향상을 보였다. 특히, 반복 Detector 중 MAP 알고리즘을 적용한 경우에는 약 4.4dB의 성능차까지 나타냈다.