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Two-way laser regeneration pseudocode rangefinder of intersatellite optical crosslink

OPTICAL ENGINEERING 2020年第3期59卷

作者： Yu, Xiaonan Tong, Shoufeng Zhao, Xin Jiang, Jun Chen, Xingchi Changchun Univ Sci & Technol Natl & Local Joint Engn Res Ctr Space Optoelect T Changchun Peoples R China Changchun Univ Sci & Technol Coll Elect & Informat Engn Changchun Peoples R China Chinese Acad Sci Innovat Acad Microsatellites Shanghai Peoples R China

The millimeter-level bidirectional long-distance asynchronous ranging has long been a huge challenge in the field of measurement and instrumentation. Correspondingly, a laser pseudocode ranging algorithm based on regenerative synchronization mechanism is proposed to address the problems obstructing precise distance measurement between asynchronous satellites. First, the synchronization strategy of a double-ended asynchronous terminal based on the regenerative pseudocode is discussed. Subsequently, we look at the algorithm of the generation, transmission, detection, and the code phase tracking loop, which forms the base of obtaining high precision of pseudocode ranging. On this basis, the error of laser pseudocode ranging link is analyzed, which mainly incorporates receiver noise and clock error. In terms of receiver noise, the influence of the photodetector carrier-to-noise ratio on random noise distribution is evaluated, and the design of receiver parameters is guided as such. As for the clock error, we look at the constraint relationship between the range and the precision under the action of the clock error, which provides the basis for the selection of the clock. Finally, the optimized system is tested when a double-ended laser link is set up in the laboratory. As a result, the comprehensive accuracy results of 3.47 mm systematic error and +/- 1.73 mm random error is obtained, and the long-scale measurement performance has been tested by the temperature-compensated crystal oscillator pulse frequency experiment. In conclusion, the experiment is consistent with the theory proposed in this study, which provides a theoretical and experimental basis for longdistance high-precision intersatellite ranging. (C) 2020 Society of Photo-Optical Instrumentation Engineers (SPIE)

关键词： laser crosslink regenerative ranging pseudonoise code clock synchronization

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Joint acquisition of PN code and adaptive beamforming weight in spread spectrum systems

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ELECTRONICS LETTERS 2004年第1期40卷 52-53页

作者： Zhang, YG Bao, Z Zhang, LR Liao, GS Xidian Univ Inst Elect Engn Xian 710071 Peoples R China

A novel approach called spatial-temporal correlator (STC) is proposed for joint acquisition of pseudonoise (PN) code and adaptive beam-forming weight in direct-sequence spread-spectrum systems with antenna array. Detection performance of the proposed STC is theoretically analysed and simulated under Gaussian jamming. These results show that the proposed scheme has improved acquisition performance and constant false alarm rate (CFAR) is achieved.

关键词： Electromagnetic compatibility and interference error statistics pseudonoise code space-time adaptive processing array signal processing codes antenna phased arrays single dwell serial search acquisition constant false alarm rate direct-sequence spread-spectrum systems Gaussian jamming Gaussian distribution correlation methods adaptive beamforming weight antenna array Rayleigh channels jamming Wiener filters Antenna arrays pseudonoise codes joint acquisition Filtering methods in signal processing spread spectrum communication Rayleigh fading channel spatial-temporal correlator Radio links and equipment Wiener filter-based beamforming

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Design, analysis and applications of PAM-PN code and PPM-PN code

Design, analysis and applications of PAM-PN code and PPM-PN ...

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4th International Conference on Microwave and Millimeter Wave Technology

作者： Liu, JB Lu, JW Xiong, G NUST Sch Elect Engn & Optoelect Technol Nanjing 210094 Peoples R China

ISBN: (纸本)0780384016

In the paper, PAM-PN code and PPM-PN code are designed and their autocorrelation function and power spectrum are deduced. And then, their features are compared and summarized, which shows that compared with single PN code, they have not only better characteristics of ranging and velocity measurement, but also better characteristics of ECCM. Furthermore, they are also easy to realize because of their periodicity. At last, as an application example of PPM-PN code, a PN code phase modulation and pseudorandom PPM combined fuze is introduced.

关键词： pulse amplitude modulation pulse position modulation pseudonoise code autocorrelation function power spectrum fuze

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Efficient pseudonoise code design for spread spectrum wireless communication systems

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS II-EXPRESS BRIEFS 2001年第6期48卷 606-613页

作者： Wu, ML Wen, KA Huang, CW Integrated Circuit Solut Inc Log Res & Dev Dept 1 Hsinchu Taiwan Natl Chiao Tung Univ Dept Elect Engn Hsinchu Taiwan

Power and bandwidth efficient communication schemes are of major concerns in wireless communication systems. One kind of efficient pseudonoise code is proposed in this paper that provides combined power-bandwidth efficiency. A novel algorithm for verifying the power and bandwidth efficient properties of a pseudonoise code is proposed with systematic analysis on code parameters. Applications of the derived codes had been implemented on 802.11 DS/SS system, which performs 36% bandwidth reduction and 14% power consumption reduction. Several new pseudonoise codes with different code lengths are also proposed.

关键词： bandwidth reduction CMOS implementations low power design pseudonoise code spread-spectrum communication wireless LAN

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The design and FPGA realization of the long PN code acquisition circuit based on digital matched-filter 5

The design and FPGA realization of the long PN code acquisit...

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5th International Conference on ASIC

作者： Tan, XH Yang, SZ Chongqing Univ Coll Commun Engn Chongqing 400044 Peoples R China

ISBN: (纸本)078037889X

In a Low-earth-orbit (LEO) satellite system the received signal will be characterized by low signal to noise, it requires a minimum spreading processing gain of 30dB. i.e., the pseudonoise (PN) code length is 1023. However, the Application specific Integrated Circuit (ASIC) based on Digital Matched-filter (DMF) for PN code acquisition on the market can't support such a long PN code length. It is necessary to use Field Programmable Gate Array (FPGA) to design the long PN code acquisition circuit based on DMF for the so high spreading processing gain. In this paper, the PN code acquisition circuit based on DMF is analyzed. A new approach to PN code acquisition based on DMF, which can obtain high spread processing gain (30dB) while the cost of the hardivare is largely depressed, is presented. VDHL design, verification and FPGA realization of the DMF is accomplished. and main design results are also given.

关键词： integrated circuit design field programmable gate arrays pseudonoise codes digital filters matched filters FPGA PN code acquisition circuit digital matched-filter low-earth orbit satellite system pseudonoise code application specific integrated circuit ASIC field programmable gate array processing gain VHDL DMF 30 dB

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Adaptive acquisition of PN code in multipath fading mobile channels

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ELECTRONICS LETTERS 2002年第3期38卷 135-137页

作者： Kim, CJ Elect Telecommun Res Inst Dev Div IMT2000 Taejon 305600 South Korea

The adaptive acquisition processor (A-A-P), which controls false alarms and reduces miss detection of multipath signals by estimating the threshold level after censoring some highest samples in the sliding window. was introduced by the present author. In addition, an AAP was analysed in a single path situation. Here, the detection performance of an AAP in multipath situations, which may exist in the sliding window, is investigated. Results show that the AAP has good performance if the number of excision samples, Ne. is greater than or equal to the number of multipath signals in the window.

关键词： time hypothesis testing scheme mobile radio error statistics pseudonoise code sliding window phase shift keying Mobile radio systems codes false alarms adaptive signal detection threshold level multipath fading mobile channels multipath channels binary phase shift keying spreading pseudonoise codes detection performance Signal detection miss detection spread spectrum communication adaptive acquisition processor fading channels

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