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探析定向宽/多频带无线通信天线的设计与应用
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作者 庆东植 《电脑乐园》 2018年第8期261-261,共1页
移动通信系统天线的稳定性是关注焦点,考虑到复杂电磁环境下的特性,要重点探讨宽带定向天线的设计和应用,解决宽带定 向天线覆盖频段宽而无法完全反射不同频率反射底板的问题,合理设计双频宽带定向电磁偶极子天线和宽/多频带定向偶极子... 移动通信系统天线的稳定性是关注焦点,考虑到复杂电磁环境下的特性,要重点探讨宽带定向天线的设计和应用,解决宽带定 向天线覆盖频段宽而无法完全反射不同频率反射底板的问题,合理设计双频宽带定向电磁偶极子天线和宽/多频带定向偶极子天线。 展开更多
关键词 定向 宽/多频带 无线通信 天线 设计
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Low-complexity and fast convergent multiuser detections for impulse UWB systems
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作者 郑霖 Qiu Hongbing 《High Technology Letters》 EI CAS 2008年第2期141-146,共6页
To solve the problem that the conventional detections in DS-CDMA suffer from high complexity and poor robustness for the time-hopping pulse signals, the received pulse signals were remodeled, and a mulfipath-free dete... To solve the problem that the conventional detections in DS-CDMA suffer from high complexity and poor robustness for the time-hopping pulse signals, the received pulse signals were remodeled, and a mulfipath-free detection scheme, which provides a simple approach to select samples of received signals, was introduced. By this scheme, the subsequent multiuser detection (MUD) would get rid of the mis- match due to the correlative multipath signal in IR-UWB. In addition, a computationally efficient recur-sive least squares (RLS) type algorithm based on least mean fourth (LMF) criterion is derived to suppress multi-access interference. The proposed multiuser detection algorithm performs well at low complexity, even in dense muhipath environment. 展开更多
关键词 ULTRA-WIDEBAND multiuser detection (MUD) multipath interference (MPI) leastmean fourth (LMF)
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Multiple Reader Algorithm for Sports Timing Systems and Its Application at Low Frequency Bandwidth 被引量:2
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作者 Min-Ho Paek Choon-Seong Leem Dae-Jung Bae 《China Communications》 SCIE CSCD 2013年第12期16-24,共9页
In sports timing systems,P2P communication is used at low frequency bandwidths(under 135 KHz) between tags and readers in the RFID field.However,in such cases,collisions tend to occur when a reader deals with multiple... In sports timing systems,P2P communication is used at low frequency bandwidths(under 135 KHz) between tags and readers in the RFID field.However,in such cases,collisions tend to occur when a reader deals with multiple RFID tags simultaneously.To overcome this issue,a sports timing system including a Multi Reader Controller(MRC)loaded with an advanced multiple reader algorithm and application was created and applied at large-scale citizens' marathon events.In these cases,a large number of people pass over the installed urethane type's antenna mat continually during a short period of time.This study verified the superiority of the improved algorithm and application through the on-thespot application of the multi reader algorithm and application program,which allows us to smoothly measure runners' times through multiaccess reading for rapid collision avoidance. 展开更多
关键词 multiple reader frequency interfer-ence collision phenomenon collision algorithm
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Performance of multi-band orthogonal frequency division multiplexing ultra wide-band system on IEEE UWB channels
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作者 王纯 《Journal of Chongqing University》 CAS 2007年第1期63-66,共4页
Multiband orthogonal frequency division multiplexing (MB-OFDM) ultra wide-band (UWB) is a novel wireless communication technology. It has many advantages and is being actively researhed. In this study, we constructed ... Multiband orthogonal frequency division multiplexing (MB-OFDM) ultra wide-band (UWB) is a novel wireless communication technology. It has many advantages and is being actively researhed. In this study, we constructed and implemented a simulation model of UWB communication systems in Simulink. We found the MB-OFDM UWB system has the best performance in distance between 4 m to 10 m without the line-of-sight requirement. 展开更多
关键词 ultra wide-band (UWB) multiband (MB) orthogonal frequency division multiplexing (OFDM)
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P×N IFFT FOR OFDM-BASED UWB SYSTEM
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作者 Zhang Zaichen Bi Guangguo 《Journal of Electronics(China)》 2007年第1期116-118,共3页
In this letter,P × N-pointIFFT is proposed to replace the N-point IFFT and analog fre-quency conversion in an Orthogonal Frequency Division Multiplexing (OFDM)-based Ultra-WideBand (UWB) system,and a new algorith... In this letter,P × N-pointIFFT is proposed to replace the N-point IFFT and analog fre-quency conversion in an Orthogonal Frequency Division Multiplexing (OFDM)-based Ultra-WideBand (UWB) system,and a new algorithm,named fast P × N-pointIFFT,is designed to reduce the com-plexity of the P × N-pointIFFT in the proposed scheme. 展开更多
关键词 Orthogonal Frequency Division Multiplexing (OFDM) Inverse Fast Fourier Transform (IFFT) Ultra-WideBand (UWB)
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Enhanced multiple access schemes for future broadband satellite communications
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作者 贾敏 顾学迈 郭庆 《Journal of Central South University》 SCIE EI CAS 2010年第1期117-122,共6页
A new structure of next generation integrated communication system was proposed, which is composed of space segment based on satellites and terrestrial segment. Moreover, the characteristics of enhanced multiple acces... A new structure of next generation integrated communication system was proposed, which is composed of space segment based on satellites and terrestrial segment. Moreover, the characteristics of enhanced multiple access schemes based on orthogonal frequency division multiplexing (OFDM) technique were analyzed for satellite links. However, OFDM is a doubtful candidate as its higher peak-to-average power ratio (PAPR) that causes the distortion of high power amplifier (HPA). Furthermore, different schemes were evaluated and compared in terms of the HPA nonlinearity and the link level performance in detail. And the pilot-aided channel estimation and equalization techniques were also considered for analyzing the problem. Simulation results show that the bit error rate (BER) and block error rate (BLER) performance of orthogonal frequency division multiple access (OFDMA) outperforms that of single carrier-frequency division multiple access (SC-FDMA) for the satellite links in the proposed structure, though discrete Fourier transform-spread OFDM DFT-S OFDM has low PAPR, especially the BER performance of OFDMA is 3.6 dB larger than that of SC-FDMA at the target BER. 展开更多
关键词 SATELLITE orthogonal frequency division multiplexing discrete Fourier transform high power amplifier channel estimation
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