A Study on Performance Improvement of Adaptive SLC System Using Eigenanalysis Method and Comparing with RLS Method
정신철Sin Chul Jung,김세연Se Yon Kim,이병섭Byung Seub Lee
5(2) 111-122, 2001
정신철Sin Chul Jung,김세연Se Yon Kim,이병섭Byung Seub Lee
DOI: JANT Vol.5(No.2) 111-122, 2001
In this paper, we study the performance of eigencanceller which use a eigenvector and eigenvalue in order to update a weighter vector. Eigencanceller can suppress directional interferences and noise effectively while maintaining specified beam pattern constraints. The constraints and optimal weight vector of eigencanceller vary by using interference and noise or desired signal, interference signal and noise as array input signal. From the analysis results in the steady state, We show that weight vectors in each case are simplified the form of projection euation that belongs to desired subspace orthogona to interference subspace and eigencanceller has the better performance than RLS method through mathematical analysis and simulation.
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A 3-D Visualization Method for Geographical Information based on Contour Lines
한정규Jung Kyu Han,백중환Joong Hwan Baek,황수찬Soo Chan Hwang
5(2) 123-133, 2001
한정규Jung Kyu Han,백중환Joong Hwan Baek,황수찬Soo Chan Hwang
DOI: JANT Vol.5(No.2) 123-133, 2001
The existing visualization methods using the satellite images or map impges require complicated preprocessing stages and a large amount of visul data to represent the 3-D terrain. This paper presents a 3-D visualization method for geographical information, which enables automatic generation of 3-D terrain. It is generated based on contour information obtained from a numerical map. This paper also introduces a method that resolves the three main problems needed to visualize 3-D terrain from contour lines such as correspondence, tiling, and branching. The virtual contour line is defined to extend a distorted contour line to have a similar shape to the corresponding contour line that is used to generate 3-D surfaces. It helps that 3-D terrain is represented exactly and in detail.
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Design of Pulse Tranceiver for Antipodal Ultra Wideband System
이정식Jung Suk Lee,김유창Yoo Chang Kim,김원후Won Hoo Kim
5(2) 134-140, 2001
이정식Jung Suk Lee,김유창Yoo Chang Kim,김원후Won Hoo Kim
DOI: JANT Vol.5(No.2) 134-140, 2001
Ultra Wideband (UWB) system uses wide band signal, which power spectral density likes as a noise floor, so UWB system can be used high speed communication without interfering with other communication system. As this system doesn`t use carrier, its structure would be very simple and consume very low power. But conventional UWB system uses Pulse Positioning Modulation(PPM) Method. Therefore it could be to produce discrete power spectrum which decreases system efficiency unintentionally. For eliminating discrete power spectrum and further Euclidean distance, we propose UWB system using Antipodal signal. And we design and simulate antipodal tranceiver using Advanced Design System (ADS).
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A Study on the Design of Elliptic - Function Narrow - Band Bandpass Filters for Tx RF of the IMT - 2000 Mobile Equipment
이상원Sang Won Lee,정명래Myung Rae Chung,김학선Hak Sun Kim,홍신남Shin Nam Hong
5(2) 141-148, 2001
이상원Sang Won Lee,정명래Myung Rae Chung,김학선Hak Sun Kim,홍신남Shin Nam Hong
DOI: JANT Vol.5(No.2) 141-148, 2001
This paper describe the development of narrow-band passband filter with small package and low loss, high selectivity performance. This filter is placed between power amplifier and frequency mixer of IMT-2000 mobile equipment. The elliptic-function narrow-band passband filter is designed with new architecture using the microstrip line. This package is very small by 3.2 cm × 1.25 cm and have the 3 % 3 ㏈ bandwidth. Also in the passband the insertion loss is about 2.5 ㏈ and is better than older RF SAW filter(insertion loss: 3.2 ㏈). In the stop-band it has the two deep notch under the -56 ㏈.
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Multi - Channel Data Link Module Design for High Speed Image Data Transmission from Spaceborne SAR
곽영길Young Kil Kwag
5(2) 149-157, 2001
곽영길Young Kil Kwag
DOI: JANT Vol.5(No.2) 149-157, 2001
A high speed data link capability is one of the critical factors in determining the performance of the spaceborne SAR system with high resolution. It is due to the strict requirement for the real-time data transmission from a series of massive raw image data of spaceborne SAR to the ground station in a limited time of mission. In this paper, based on the data link model characterized by the spaceborne small SAR system, the high rate multi-channel data link module is designed including link storage, link processor, transmitter, and wide-angle antenna. The design results are presented with the performance analysis on the data link budget as well as the multi-mode data rate in association with the SAR imaging mode of operation from high resolution to the wide swath.
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Improvement Performance of Inter - Vehicle Communication System in Millimeter Wave RF Channels
김춘구Choon Gu Kim,강희조Heau Jo Kang,최용석Yong Suk Choi
5(2) 158-164, 2001
김춘구Choon Gu Kim,강희조Heau Jo Kang,최용석Yong Suk Choi
DOI: JANT Vol.5(No.2) 158-164, 2001
We presented a channel model for the inter vehicle radio link including the reflection from the road surface, side road vehicle and concrete wall. Then we theoretically derived the path loss and delay profile characteristics using the Ray tracing method efficiently analyzing millimeter wave or optic wave. Finally, we shown the improvement of propagtion characteristics by diversity techniques, BCH coding and convolution coding techniques. At the result, MRC diversity techniques and BCH coding can`t obtained PER =10^-6 which is considered to be data service criterion. But we knew that Packet Error Rate Characteristic can obtained PER=10^-6, which is considered to be data serivice criterion, when convolution coding scheme are adopted in Rician fading.
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Performance Estimation and Design for the Next DSRC System using OFDM
고윤진Yun Jin Ko,전재춘Jae Choon Jeon,정미선Mee Seon Jeong,황인관In Kwan Hwang,안동현Dong Hyun Ahn,임춘식Choon Sik Yim
5(2) 165-174, 2001
고윤진Yun Jin Ko,전재춘Jae Choon Jeon,정미선Mee Seon Jeong,황인관In Kwan Hwang,안동현Dong Hyun Ahn,임춘식Choon Sik Yim
DOI: JANT Vol.5(No.2) 165-174, 2001
In this paper, we investigated performance for 5.8GHz dedicated short range communication system using OFDM which will be applied to Intelligent transportation system services. We analyzed modulation technique and interference cancellation method to improve performance in physical layer. We presented channel model to estimate performance between Roadside Unit and Onboard Unit. finally. We calculated the link budget of entire system which analyzed performance of channel according to transmission power, presented the adaptive modulation using pilot signal and RSSI algorithm is proposed.
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