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A Novel High Spectral Efficiency Waveform Coding-OVFDM 被引量:2
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作者 LI Daoben 《China Communications》 SCIE CSCD 2015年第2期61-73,共13页
Based on the Overlapped Multiplexing Principle[12],a frequency domain OVFDM(Overlapped Frequency Domain Multiplexing) Coding is proposed.By the data weighted shift overlapped version of any band-limited Multiplexing T... Based on the Overlapped Multiplexing Principle[12],a frequency domain OVFDM(Overlapped Frequency Domain Multiplexing) Coding is proposed.By the data weighted shift overlapped version of any band-limited Multiplexing Transfer Function H(f) the coding gain and spectral efficiency are both achieved.The heavier the overlap of the data weighted Multiplexing Transfer Function H(f),the higher the coding gain and spectral efficiency as well as the closer the output to the optimum complex Gaussian distribution.The bit error probability performance is estimated.The time domain OVTDM(Overlapped Time Domain Multiplexing) Coding,the dual of OVFDM in time domain is incidentally proposed as well.Both theoretical analysis and testified simulations show that OVFDM(OVTDM) is suitable for high spectral efficiency application and its spectral efficiency is only roughly linear to SNR rather than the well-known logarithm to SNR. 展开更多
关键词 overlapped multiplexing principle frequency domain coding waveform coding spectral efficiency shannon capacity dual relation OVFDM OVTDM
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Degradation of effective carrier-power-to-noise densityratio based on code trackingspectral sensitivitycoefficient for GNSS radio frequencycompatibilityin C band
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作者 刘美红 战兴群 牛满仓 《Journal of Beijing Institute of Technology》 EI CAS 2014年第3期413-419,共7页
The frequency band between 5 010 MHz and 5 030 MHz allocated as C band has been used as a candidate in the global navigation satellite systems (GNSS) along with more and more naviga- tion services in L band. The pot... The frequency band between 5 010 MHz and 5 030 MHz allocated as C band has been used as a candidate in the global navigation satellite systems (GNSS) along with more and more naviga- tion services in L band. The potential benefits and technical requirements of C band for satellite navi- gation have been analyzed before. However the degradation of effective carrier-power-to-noise densi- ty ratio( A (C/No )eu) based on code tracking spectral sensitivity coefficient( CT_SSC ) as a compati- bility assessment methodology for potential GNSS radio frequency compatibility in C-Band has not been discussed clearly. So the compatibility of the signals in the C band between BeiDou (BD) B1 C and GPS L1C, L1C/A, Galileo E1Os as the interoperability or classical signals in L band is analyzed. Simulation results reveal the interference degree between BD III B1C and GPS L1C/A, L1C, Galileo E1OS. The results can also reveal that the multiplexed binary offset carrier (MBOC) and binary phase shift keying (BPSK) modulation is not appropriate for C band. 展开更多
关键词 degradation of effective carrier-power-to-noise density ratio code tracking spectral sen-sitivity coefficient compatibility
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A new multi-model coding algorithm based on MBE and spectral amplitude correlation between successive frames 被引量:1
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作者 PAN Shengxi LIU Jia +1 位作者 WANG Zuoying LU Dajin(Dept. of Electronic Engineering, Tsinghua University Beijing 100084) 《Chinese Journal of Acoustics》 1998年第3期227-233,共7页
The researches on spectral amplitude correlation between successive frames based on MBE (Multi-Band Excitation) are presented and a new MBE coding algorithm of muitimodels is proposed. It has been shown that the magni... The researches on spectral amplitude correlation between successive frames based on MBE (Multi-Band Excitation) are presented and a new MBE coding algorithm of muitimodels is proposed. It has been shown that the magnitude spectrum in MBE coding algorithm can be estimated in very high accuracy by using a simple linear predictive model of the spectral amplitude correlation between successive frames. This model employs oniy one gain coefficient and one predictive coefficient. The accuracy of estimated magnitude spectrum in this model is higher than that of the conventional MBE algorithm using the 10-th order LPC (Linear Predictive Coding) Inodel without the spectral amplitude correlation between successlve frames.This model is superior to the conventional MBE coding model in volced speech, but it is iess effective in unvoiced speech, so that the conventional MBE coding algorithm is still used for unvoiced speech. The new multi-model coding algorithm improves the quality of coding speech,and obtains good results 展开更多
关键词 MBE A new multi-model coding algorithm based on MBE and spectral amplitude correlation between successive frames LPC
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Performance Analysis of 112Gb/s×4-Channel WDM PDM-DQPSK Optical Label Switching System With Spectral Amplitude Code Labels
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作者 Isaac Adjaye ABOAGYE Fushen CHEN Yongsheng CAO 《Photonic Sensors》 SCIE EI CAS CSCD 2017年第1期88-96,共9页
We present the performance analysis of ll2Gb/s-4 wavelength division multiplexing (WDM) 100GHz channel spacing polarization division multiplexed-differential quadrature phase shift keying (PDM-DQPSK) optical label... We present the performance analysis of ll2Gb/s-4 wavelength division multiplexing (WDM) 100GHz channel spacing polarization division multiplexed-differential quadrature phase shift keying (PDM-DQPSK) optical label switching system with frequency swept coherent detected spectral amplitude code labels. Direct detection is chosen to demodulate the payload by applying a polarization tracker, while 4-bits of 156Mb/s spectral amplitude code label is coherently detected with a scheme of frequently-swept coherent detection. We optimize the payload laser linewidth as well as the frequency spacing between the payload and label. The label and payload signal performances are assessed by the eye-diagram opening factor (EOF) and bit-error rate (BER) at 10 9 as a function of the received optical power (ROP) and the optical signal to noise ratio (OSNR). The payload could well be demodulated after 900 km at a bit error rate of 10-3 using forward error correction (FEC). 展开更多
关键词 Optical label switching (OLS) polarization division multiplexed (PDM) spectral amplitude code(SAC) wavelength division multiplexing (WDM)
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Vision algorithms for fixed-wing unmanned aerial vehicle landing system 被引量:9
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作者 FAN YanMing DING Meng CAO YunFeng 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2017年第3期434-443,共10页
Autonomous landing has become a core technology of unmanned aerial vehicle(UAV)guidance,navigation and control system
关键词 vision-based landing spectral residual sparse coding position and pose estimation orthogonal iteration
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