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2025 IEEE Underwater Technology, UT 2025

作者： Yeh, Chan-Chia Chen, Qing-Da Huang, Chen-Fen Guo, Jen-Hwa National Taiwan University Department of Engineering Science and Ocean Engineering Taipei Taiwan Institute of Oceanography National Taiwan University Taipei Taiwan Science and Ocean Engineering Department of Engineering Taipei Taiwan

ISBN: (纸本)9798331534189

The challenges of underwater acoustic communication in shallow water environments are dominated by severe multipath propagation and dynamic channel variations, resulting in intersymbol interference (ISI) and Doppler shifts from mobile platforms. This paper introduces an innovative communication architecture that combines three key techniques: pulse position modulation (PPM), multi-Doppler matched filtering, and virtual time-reversal (VTR). The system's cornerstone is a novel block-wise VTR approach that adaptively responds to channel variations while maintaining signal clarity. Initial system validation through water tank experiments demonstrated successful signal processing and hardware implementation under controlled conditions. The system's reliability was further verified through simulations incorporating real field environments and actual seafloor topography. Experimental results showed successful decoding of all test transmissions, while simulations confirmed robust performance under complex channel conditions. Field experiments are planned to evaluate system performance in dynamic ocean environments, where mobile platforms and varying oceanographic conditions present additional challenges. Our integrated approach presents a significant advancement in reliable underwater communication for complex nearshore environments, with potential applications in marine research, ocean exploration, and autonomous underwater vehicle operations. © 2025 IEEE.

关键词： pulse position modulation

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Research on Laser Simultaneous Wireless Information and Power Transfer Based on pulse position modulation 11th

Research on Laser Simultaneous Wireless Information and Powe...

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11th Frontier Academic Forum of Electrical Engineering, FAFEE 2024

作者： Wang, Yuyang Zhou, Weiyang Wang, Zhuang Li, Jincheng Jin, Ke Department of Electrical Engineering Nanjing University of Aeronautics and Astronautics Nanjing Nanjing China

ISBN: (纸本)9789819788156

A Laser Simultaneous Wireless Information and Power Transfer (LSWIPT) system based on pulse position modulation (PPM) has been proposed. To achieve the goals of high power and high communication rates, a novel approach utilizing a combination of high-amplitude constant DC current and pulse current at the transmitter has been adopted. In this scheme, constant DC current serves as the primary power output, while pulse current accounts for a smaller portion. Additionally, a laser pulse current source based on LCL resonant converter has been designed to facilitate L-PPM (Single pulse position modulation) by dynamically adjusting the position of the pulse current while maintaining a constant duty cycle. This innovative technique ensures stable pulse power while allowing for the loading of information, effectively decoupling power and information transmission within the system. Furthermore, a system prototype has been constructed and the feasibility of the proposed approach has been validated through a comprehensive analysis involving both simulation and experimental methods. Under the condition of transmitting high power in the system, the communication rate also rises to 400 kbps. © Beijing Paike Culture Commu. Co., Ltd. 2025.

关键词： pulse position modulation

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pulse position modulation for compact all-fiber vehicle laser rangefinder development

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OPTICAL ENGINEERING 2017年第10期56卷 107102-107102页

作者： Mao, Xuesong Cheng, Yongzhi Xiong, Ying Inoue, Daisuke Kagami, Manabu Wuhan Univ Sci & Technol Sch Informat Sci & Engn Wuhan Hubei Peoples R China Wuhan Univ Sci & Technol Coll Comp Sci & Technol Wuhan Hubei Peoples R China Toyota Cent R&D Labs Environm Sensing Lab Nagakute Aichi Japan

We propose a method for developing small all-fiber vehicle laser rangefinders that is based on pulse position modulation (PPM) and data integration and present a theoretical study on its performance. Compared with spatial coupling, which is employed by most of the current commercial vehicle laser rangefinders, fiber coupling has the advantage that it can guide laser echoes into the interior of a car, so the electronic components following the photodiode can operate in a moderate-temperature environment. However, optical fibers have numerical apertures (NAs), which means that a laser beam from a receiving lens cannot be coupled into an optical fiber if its incident angle exceeds the critical value. Therefore, the effective size of the receiving lens is typically small since it is limited by its focal length and the NA of the fiber, causing the power of the laser echoes gathered by the receiving lens to be insufficient for performing target identification. Instead of increasing the peak transmitting laser power unrestrictedly, PPM and data integration effectively compensate for the low signal-to-noise ratio that results from the effective receiving lens size reduction. We validated the proposed method by conducting numerical simulations and performance analysis. Finally, we compared the proposed method with pseudorandom noise (PN) code modulation and found that, although the two methods perform equally well in single-target measurement scenarios, PPM is more effective than PN code modulation for multi-target measurement. In addition, PPM enables the transmission of laser beams with higher peak powers and requires less computation than PN code modulation does. (C) 2017 Society of Photo-Optical Instrumentation Engineers (SPIE)

关键词： pulse position modulation data integration laser rangefinder road targets sensing

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pulse position modulation coding schemes for optical intersatellite links

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ELECTRONICS LETTERS 2010年第4期46卷 290-U43页

作者： Ghosna, F. J. Sibley, M. J. N. Univ Huddersfield Dept Engn & Technol Sch Comp & Engn Huddersfield HD1 3DH W Yorkshire England

The rapid and significant development of communications links between satellites has made it possible to use various applications such as relay voice, video, multimedia, etc. As a result, much research has been carried out in this field during recent years to reduce power consumption and increase transmission reliability. This reported work focuses on analysis of intersatellite links in free space, with optical links using laser sources being considered in particular. The use of several different coding schemes are discussed for use in such links: multiple pulse position modulation (MPPM);digital pulse position modulation (DPPM);Dicode pulse position modulation (Dicode PPM). Work has been carried out to compare these coding schemes in terms of error weightings and coding efficiency through showing how the PCM error rate is affected by false alarm and erasure errors for MPPM, DPPM and Dicode PPM coding 3 bits of PCM. Comparison between these coding schemes is drawn in terms of sensitivity and bandwidth efficiency.

关键词： Dicode pulse position modulation communications links digital pulse position modulation error rate free space laser sources multiple pulse position modulation optical intersatellite links optical links power consumption power consumption pulse code modulation links pulse position modulation pulse position modulation coding satellite links telecommunication network reliability transmission reliability

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pulse position modulation for FSO Systems: Capacity and Channel Coding

Pulse Position Modulation for FSO Systems: Capacity and Chan...

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10th International Conference on Telecommunications (ConTEL 2009)

作者： Xu, F. Khalighi, M. A. Bourennane, S. Ecole Cent Marseille Inst Fresnel CNRS UMR 6133 Marseille France

ISBN: (纸本)9789531841313

For terrestrial free space optical (FSO) systems, we investigate the use of pulse position modulation (PPM) which has the interesting property of being average-energy efficient. We first discuss the upper bound on the information transmission rate for a Gaussian channel. Next, we consider the more practical aspect of channel coding and look for a suitable solution for the case of Q-ary PPM. Instead of using a non-binary channel code, we suggest to use a simple binary convolutional code and to perform iterative soft demodulation (demapping) and channel decoding at the receiver. We show that the proposed scheme is quite efficient against demodulation errors due to the receiver noise. Moreover, we propose a simple soft-demapping method of low complexity for the general case of Q-ary PPM. The receiver complexity remains then reasonable in view of implementation in a terrestrial FSO system.

关键词： pulse position modulation

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pulse position modulation for active RFID system

Pulse position modulation for active RFID system

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11th International Conference on Parallel and Distributed Systems

作者： Zhen, B Mizuno, K Kobayashi, M Shimizu, M Natl Inst Informat & Commun Technol Yokosuka Kanagawa 2390847 Japan

ISBN: (纸本)0769522815

Radio frequency identification (RFID) enables everyday objects to be identified, tracked, and recorded. This paper presents a design of N-ary pulse position modulation transmission-only active RFID system for monitoring of large number and high density objects. A burst frame from tag consists of multiple duplicated blink units and the interval between them is randomly selected from predefined interval steps to avoid continuous collision. The reader segments composite pulse streams and performs cross-correlation to recover the overlapped blink unit. The tag can be read in registration state or pattern matching state. Simulations show that the system is power efficient, large capacity, and fast reactive.

关键词： pulse position modulation

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pulse position modulation Based On Phase Locked Loop

Pulse Position Modulation Based On Phase Locked Loop

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6th International Conference on Electrical Engineering/Electronics, Computer, Telecommunications and Information Technology

作者： Wisartpong, P. Koseeyaporn, J. Wardkein, P. King Mongkuts Inst Technol Ladkrabang Fac Engn Dept Telecommun Engn Bangkok 10520 Thailand

ISBN: (纸本)9781424433872

It is well know that pulse position modulation (PPM) play an important role in optical and wireless communication, because of they save the power for transmission and obtained the high utilization of bandwidth. Consequently, in this paper PPM based on phase locked loop (PLL) with carrier and without carrier are proposed. It can easily adjust carrier frequency by tuning reference signal frequency of PLL. The proposed circuit is compose of voltage control oscillator (VCO), RC low pass loop filter, two mono stable multi vibrator and RS F/F. In order to obtain the PPM with carrier, we only add both output mono stable multi vibrator together. The experimental result show that this proposed PPM circuit work well and it is a compact size, when we compare with various signals that it can generate, such as pulse Width modulation (PWM), PPM, with and without carrier.

关键词： Phase locked loop pulse width modulation pulse position modulation

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pulse position modulation for a subcarrier multiplexed optical fibre transmission system

Pulse position modulation for a subcarrier multiplexed optic...

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Conference on All-Optical Communication Systems - Architecture, Control, and Network Issues II

作者： Wickramasinghe, VR Ghassemlooy, Z SHEFFIELD HALLAM UNIV SCH ENGNELECT & COMMUN ENGN RES GRPSHEFFIELD S1 1WBS YORKSHIREENGLAND

ISBN: (纸本)0819423211

Subcarrier multiplexed (SCM) optical networks offer a near to medium term alternative solution over high cost, evolving digital technology to distribute broadband services. Majority of existing systems are based on analogue optical transmission techniques and their principle disadvantage is the sensitivity to noise and system nonlinearities. Therefore, conventional SCM systems impose stringent noise and linearity requirements and as a result their performance is limited. A simple and attractive solution is to introduce an appropriate second stage modulator in order to improve the receiver sensitivity, hence the system performance. In this paper a SCM optical transmission system employing pulse position modulation (PPM) as a second stage modulator, for transmission of video, audio and data channels is reported. Signal to noise ratio measurements obtained shows an improvement in optical receiver sensitivity compared with standard SCM systems.

关键词： subcarrier multiplexed systems pulse position modulation optical communication pulse time modulation

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pulse position modulation Spread Spectrum Underwater Acoustic Communication System using N-H Sequence

Pulse Position Modulation Spread Spectrum Underwater Acousti...

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IEEE International Conference on Signal Processing, Communications and Computing (ICSPCC)

作者： Tang Zheng Zhou Feng Zheng Wenting CETC Key Lab Data Link Technol Xian Peoples R China Harbin Engn Univ Sci & Technol Underwater Acoust Lab Harbin Peoples R China

ISBN: (纸本)9781509027088

Conventional underwater acoustic (UWA) spread spectrum communication technology usually uses m sequence as a spreading code, but pulse position modulation (PPM) spread spectrum system utilizes the aperiodic autocorrelation function (AACF) characteristic of a sequence. M sequence is not the best choice in case of AACF. To solve this problem, and based on the fine AACF property of N-H sequence, PPM spread spectrum UWA communication system using N-H sequence was proposed in this paper. And then we compared the correlation function property between the two sequences and the PPM system performance using two sequences to testify the superior performance of the approach we proposed.

关键词： Underwater acoustic communication pulse position modulation N-H sequence

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pulse position modulation/demodulation with picosecond slot widths

Pulse position modulation/demodulation with picosecond slot ...

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Free-Space Laser Communication Technologies XX

作者： Birnbaum, Kevin M. Farr, William H. Jet Propulsion Laboratory California Institute of Technology 4800 Oak Grove Dr Pasadena CA 91109

ISBN: (纸本)9780819470522

pulse position modulation (PPM) is the preferred signaling format for deep space optical communications. Its high peak to average power ratio easily supports efficient forward error correction codes that operate within one dB of capacity at efficiencies better than one bit per detected photon when using photon counting detectors. Sub-100 picosecond slot widths are desired for efficient gigabit/second data links, but slot widths are limited by the jitter of available single photon detectors and laser modulators. Presently, the slot width must be larger than the receiver detector jitter and the transmitter modulator transition times. We show techniques whereby the slot time can be reduced, such that the jitter limitation is no longer the slot width but rather the PPM symbol duration.

关键词： pulse position modulation

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