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Optimal video communication strategy for intelligent video analysis in unmanned aerial vehicle applications

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Chinese Journal of Aeronautics 2020年第11期33卷 2921-2929页

作者： Yongqiang XIE Zhongbo LI Jin QI Kai ZHANG Bixuan ZHANG Feng QI Institute of Systems Engineering Academy of Military SciencesPLABeijing 100141China National Engineering Laboratory for Video Technology Peking UniversityBeijing 100871China

For Unmanned Aerial Vehicles(UAV),the intelligent video analysis is a key technology in intelligent autonomous control,real-time navigation and ***,poor UAV wireless links would degrade the quality of video communication,leading to difficulties in video *** meet the challenges of packet-loss and limited bandwidth in adverse UAV channel environments,this paper proposes a parameter optimization mechanism for UAV intelligent video *** the proposed method,an Optimal Strategy Library(OSL)is designed to optimize the parameters for video encoding and forward error *** to the packet-loss rate and bandwidth in practical UAV wireless network,the proposed OSL can facilitate the encoding of video sequences and the recovery of degraded videos with optimal *** results demonstrate that the proposed solution can keep intelligent video analysis working efficiently with adverse UAV wireless links,and is capable of maximizing the inference accuracy of Multi-Object Tracking(MOT)algorithms in various scenarios.

关键词： forward error correction Intelligent video analysis Multi-Object Tracking(MOT) Optimal strategies UAVs Video communication

LSTM-Based Adaptive Modulation and Coding for Satellite-to-Ground Communications

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Journal of Beijing Institute of Technology 2022年第5期31卷 473-482页

作者： Shiqi Zhang Guoxin Yu Shanping Yu Yanjun Zhang Yu Zhang School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China. School of Cyberspace Science and Technology Beijing Institute of TechnologyBeijing 100081China

Satellite communication develops rapidly due to its global coverage and is unrestricted to the ground environment. However, compared with the traditional ground TCP/IP network, a satellite-to-ground link has a more extensive round trip time(RTT) and a higher packet loss rate,which takes more time in error recovery and wastes precious channel resources. forward error correction(FEC) is a coding method that can alleviate bit error and packet loss, but how to achieve high throughput in the dynamic network environment is still a significant challenge. Inspired by the deep learning technique, this paper proposes a signal-to-noise ratio(SNR) based adaptive coding modulation method. This method can maximize channel utilization while ensuring communication quality and is suitable for satellite-to-ground communication scenarios where the channel state changes rapidly. We predict the SNR using the long short-term memory(LSTM) network that considers the past channel status and real-time global weather. Finally, we use the optimal matching rate(OMR) to evaluate the pros and cons of each method quantitatively. Extensive simulation results demonstrate that our proposed LSTM-based method outperforms the state-of-the-art prediction algorithms significantly in mean absolute error(MAE). Moreover, it leads to the least spectrum waste.

关键词： satellite communication long short-term memory forward error correction rain loss adaptive modulation and coding

160-Gb/s NRZ-DQPSK optical transmission system employing QC-LDPC code

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Chinese Optics Letters 2014年第1期12卷 17-21页

作者：李莎余重秀康喆 Gerald Farrell 吴强 State key laboratory of Information Photonics and Optical communications Beijing University of Posts and Telecommunications Photonic Research Centre Dublin Institute of Technology

A quasi-cyclic low-density parity check （QC-LDPC） code is constructed by an improved stability of the shortest cycle algorithm for 160-Gb/s non-return zero differential quadrature phase shift keying （NRZ- DQPSK） optical transmission system with the fiber-based optical parametric amplifier （FOPA）. The QC- --14 d LDPC code with stability of the shortest cycle reduces the bit error ratio （BER） to 10 an restrains the error floor effectively.

关键词： forward error correction Light amplifiers Light transmission Optical parametric amplifiers

Physical Layer Deterministic Network Coding Using PUM Turbo Codes over AWGN Channel, N Nodes through a Base Station Scenario

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Communications and Network 2016年第4期8卷 241-256页

作者： Hani Attar Department of Electronic and Electrical Engineering Philadelphia University Amman Jordan

Network Coding (NC) is a recent technique which is used to improve the transmission data rate and the power efficiency. These goals are obtained by combining data together before transmitting them, resulting to less transmitted data that carry the same amount of information. NC research work over the physical layer and the upper layers are popular and needed to be more investigated. In this paper, we propose a practical system of large-number of connected multi-source network coding (LMSNC), at the physical layer that exploits the broadcast nature of the wireless channel, using the practical and bandwidth-efficient schemes decode-and-forward (DF) and then compare it with Amplify and forward (AF). The theoretical analysis and the simulation results show the effect of the noise when it cumulates in AF system and how DF is solving this severe default. Moreover, we consider the MSNC for Small-number of connected sources (SMSNC) and the two-way communication setup where two users exchange their information over an intermediate network node (ideally called Base Station), as two reference cases to compare with. With SMSNC, the number of necessary downlink transmissions from the intermediate node to the users is reduced, and thus the throughput is increased. Simulation results obtained using high-performance non-binary turbo codes, based on Partial Unit Memory (PUM) codes (4, 2, 1, 4) and (8, 4, 3, 8);confirm that combining PUM Turbo Code (PUMTC) and NC in the proposed MSNC setup gives almost the same BER performance as that for SMSNC at the small number of processing steps mainly when PUMTC (8, 4, 3, 8) is performed, which is required to retrieve the received coded messages. In the scenario of AF, combining packets results to cumulate the noise, which justifies the reason we decided to increase the number of transmitted coded messages in the network, i.e., the BER performance improves when sending extra coded messages. Finally, the possibility for a trade-off among BER, da

关键词： Network Coding Cooperative Nodes forward error correction

Technical Analysis on Application Layer error Control in IPTV

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ZTE Communications 2010年第1期8卷 55-59页

作者： Xia Hongfei Lue Xiaopeng Liu Feng ZTE Corporation Nanjing 210012 P. R. China Image Processing and Image Communication Laboratory of Jiangsu Province Nanjing University of Posts and Telecommunications Nanjing 210003 P. R. China

When they provide Internet Protocol Television （IRTV） services, IP networks face difficulties such as reduced transmission bandwidth, delay, jitter, and packet loss. A terminal-centric solution can improve the image quality by adding control policies like congestion control and error control to the receiving terminal and source code. An end-to-end application layer reliability method is usually required to satisfy IPTV requirements in the IP network. Application Layer forward error correction （AL-FEC） technology solves the problem of packet loss, and can ensure the end-to-end reliability for IPrV services.

关键词： IPTV error Control Application Layer forward error correction transmission bandwidth reliability packet loss congestion control Internet Protocol services image quality error control difficulties technology solution required improve jitter delay face

Implement of FEC in the Optical Transport Network

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Chinese Journal of Lasers 2001年第3期 40-43页

作者： FENG Jianhe JI Yuefeng GUAN Kejian (Beijing University of Posts and Telecommunications P.O.Box 125, BUPT ZTE LAB, Beijing 100876, China)

forward error correction (FEC) is a method by which extra information is included along with the original signal to provide redundancy for correcting bit errors. According to Reed Solomon code regularity, a certain amount of bit errors can be corrected. The appropriate capability of correcting burst bits in error may be more flexible implement of FEC in the optical transport network. The suitable choice can effectively reduce cost of the optical transport network.

关键词： forward error correction Reed Solomon code optical transport network BER

Transmission of 10Gb/s WDM signals over 4000 km of standard single-mode fiber with 106 km spans using all-Raman amplification and NRZ format

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Transmission of 10Gb/s WDM signals over 4000 km of standard ...