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IEEE International Symposium on Broadband Multimedia Systems and Broadcasting (BMSB)

作者： Montalban, J. Vera, A. Angueira, P. Makarov, Sergey B. Gelgor, Alexander L. Popov, Eugene A. Tkachenko, Dmitry A. Univ Basque Country UPV EHU Bilbao Engn Fac Bilbao Spain Peter Great St Petersburg Polytech Univ St Petersburg Russia

ISBN: (纸本)9781728121505

Layered Division Multiplexing (LDM) is an effective approach for increase of data rates available for different services in wireless channels. LDM is included in ATSC 3.0 digital terrestrial TV system based on orthogonal frequency division multiplexing (OFDM) modulation. At the same time, satellite DVB-S2 and DVB-S2X systems that are currently used for Direct-To-Home (DTH) broadcasting include Variable coding and modulation (VCM) mode, which actually provides the opportunity to deliver different services to the consumers with Time Division Multiplexing (TDM). From this point of view, the investigation of LDM for satellite broadcast and communication systems and its comparison with VCM (TDM) approach becomes relevant. In this paper, several use cases were considered providing the delivery of High Definition (HD) and Ultra High Definition (UHD) TV services to customers as well as additional communication services. Analysis shows that LDM provides considerable gain in comparison with VCM for each use case.

关键词： Satellite Communication Satellite Broadcasting modulation coding Multiplexing Layered Division Multiplexing Point-to-multipoint Communication Contribution links Ku Band Ka Band

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Synthesized high resolution imaging using a frequency agile waveform with costas modulated

Synthesized high resolution imaging using a frequency agile ...

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IET International Radar Conference (IET IRC 2020)

作者： Y. Wang G. Liu Y. Hou Nanjing Research Institute of Electronics Technology Nanjing 210039 People’s Republic of China

Frequency agility and complex code modulated waveforms are employed in many radars due to their good electronic counter-counter measures (ECCM) performance. Except this, another advantage of frequency agility is the synthetic wideband, which is benefit for obtaining high range resolution, i.e., one-dimensional (1D) imaging. This paper describes a combined wideband processing technique for a frequency agile waveform with Costas code modulated. Compared to the synthetic range profile (SRP) processing, the frequency-domain recombination method avoids grating lobes, and results in a better 1D imaging. This method reduces the computation compared to the SRP, and improves the recognition ability simultaneously by taking advantage of the frequency agility. These make it good for engineering application.

关键词： synthetic aperture radar frequency agility electronic countermeasures radar imaging modulation coding radar resolution radar signal processing image resolution

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Polar coded space-time block coded spatial modulation based on Plotkin's construction for coded cooperative networks

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IET COMMUNICATIONS 2018年第3期12卷 237-245页

作者： Mughal, Shoaib Yang, Fengfan Xu, HongJun Umar, Rahim Nanjing Univ Aeronaut & Astronaut Coll Elect & Informat Engn Nanjing 210016 Jiangsu Peoples R China Univ KwaZulu Natal Sch Engn King George V Ave ZA-4041 Durban South Africa

A Plotkin-based polar coded space-time spatial modulation scheme is proposed and its bit error rate (BER) performance over quasi-static Rayleigh fading channel is evaluated. The exacerbated complexity in receiver design is ameliorated by employing a low complexity soft demapper for their proposed Plotkin-based polar coded scheme. As there is a natural split present in the design of the considered Plotkin's construction, therefore the authors effectively extended their proposed scheme to coded-cooperative scenarios. In any coded-cooperative communication, the relay node always plays a pivotal role in determining the BER performance of communication system. Therefore, a rational selection criterion for selecting the information bits at the relay node is presented. The authors have also devised nested polar coded-cooperative space-time spatial modulation (NPCCST-SM) scheme as a useful benchmark. Monte-Carlo simulated results revealed that their proposed coded-cooperative scheme has triumphed conventional NPCCST-SM scheme by a gain of 0.6-0.8dB under identical conditions. Moreover, the proposed cooperative scheme outperforms its corresponding non-cooperative counterpart scheme by a gain of 1-1.2dB under identical conditions.

关键词： Monte Carlo methods relay networks (telecommunication) radio receivers channel coding Rayleigh channels error statistics cooperative communication error correction codes linear codes modulation coding space-time block codes polar coded space-time block coded spatial modulation Plotkin construction coded cooperative networks Plotkin-based polar coded space-time spatial modulation scheme bit error rate performance BER performance quasistatic Rayleigh fading channel receiver design low complexity soft demapper coded-cooperative communication relay node rational selection criterion information bits selecting nested polar coded-cooperative space-time spatial modulation scheme Monte Carlo simulation NPCCST-SM scheme gain 0 6 dB to 0 8 dB gain 1 dB to 1 2 dB

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Joint Optimization of Resource Allocation and modulation coding Schemes for Unicast Video Streaming in OFDMA Networks

Joint Optimization of Resource Allocation and Modulation Cod...

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IEEE 23rd International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC)

作者： Lin, Wei-Di Hsieh, Hung-Yun Natl Taiwan Univ Grad Inst Commun Engn Taipei 106 Taiwan

ISBN: (纸本)9781467325691

In the paper, we investigate a distortion-optimized resource allocation problem among a group of users with unicast video transmission in OFDMA networks. Since video distortion results from both encoding errors due to rate limitation and transmission errors due to packet losses, to minimize distortion we also consider joint optimization of the selection of the modulation and coding scheme (MCS) for each allocated resource unit. To proceed, we formulate a mixed-integer non-linear programming (MINLP) problem for joint resource allocation and MCS selection with the objective to minimize overall video distortions from all users. To solve the formulated problem, we propose a two-stage algorithm, where the Hungarian algorithm is used in the first stage to optimally assign the minimum resource units required for individual users based on their channel conditions. In the second stage, additional resource units are assigned to the most needed users with the greatest potential to minimize the overall distortions. As more resource units are allocated to each user, the MCS is adjusted accordingly to avoid biased selection from the initial resource unit. Simulation results show that the proposed algorithm achieves performance gain of about 16%-55% compared to the conventional approach of separate resource allocation and MCS selection.

关键词： Resource utilization Resource Units Video streaming management of resources MCS gene Unicast Consumers OFDMA rate limitation modulation coding Video transmission Packet loss

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Doppler-robust high-spectrum-efficiency VCM-OFDM scheme for low Earth orbit satellites broadband data transmission

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IET COMMUNICATIONS 2018年第1期12卷 35-43页

作者： Li, Jionghui Xiong, Weiming Sun, Geng Wang, Zhugang Huang, Yonghui Shen, Ming Chinese Acad Sci Natl Space Sci Ctr Beijing 100190 Peoples R China Univ Chinese Acad Sci Beijing 100049 Peoples R China Jilin Univ Coll Comp Sci & Technol Changchun 130012 Jilin Peoples R China Aalborg Univ Dept Elect Syst DK-9220 Aalborg Denmark

High-efficiency satellite-ground downlink data transmission system is being demanded to support increasing volume of data with limited spectrum resource. Considering the dynamic link conditions due to the orbital motion of low Earth orbit (LEO) satellite, variable coding modulated orthogonal frequency division multiplexing (VCM-OFDM) is proposed as an effective way to better exploit link resource. In this study, regarding the relative motion between the satellite on-board transmitter and the ground station receiver, filtered-OFDM signal is designed with adjustable coding modulation sets to achieve higher spectral efficiency and get along with the high-Doppler environment at the same time. Physical layer frame structure is proposed taking the Doppler frequency shift compensation into account with minimum overhead. System performance evaluations prove that transmission throughput in the dynamic communication link can be enhanced significantly by the proposed scheme, which indicates the potential for supporting future gigabit X-band reliable satellite-ground downlink transmissions.

关键词： satellite ground stations satellite links radio receivers radio transmitters OFDM modulation modulation coding Doppler shift filtering theory Doppler-robust high-spectrum-efficiency VCM-OFDM scheme low Earth orbit satellites broadband data transmission high-efficiency satellite-ground downlink data transmission system limited spectrum resource dynamic link conditions orbital motion LEO satellite variable coding modulated orthogonal frequency division multiplexing satellite on-board transmitter ground station receiver filtered-OFDM signal adjustable CODMOD spectral efficiency physical layer frame structure Doppler frequency shift compensation future gigabit X-band reliable satellite-ground downlink transmissions

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Efficient BeiDou DBZP-based weak signal acquisition scheme for software-defined receiver

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IET RADAR SONAR AND NAVIGATION 2018年第6期12卷 654-662页

作者： Meng, Qian Liu, Jian-Ye Zeng, Qing-Hua Feng, Shao-Jun Xu, Rui Nanjing Univ Aeronaut & Astronaut Nav Res Ctr Nanjing Jiangsu Peoples R China Satellite Commun & Nav Collaborat Innovat Ctr Nanjing Jiangsu Peoples R China Imperial Coll London Dept Civil & Environm Engn Ctr Transport Studies London England

modulation with high-rate Neumann-Hoffman (NH) code in BeiDou signals increases the complexity and calculation load in acquisition as the data bit transitions are more frequent and there is no pilot component for synchronisation which is used in other constellations. Among the current state of the art, double block zero padding (DBZP) method has great potential in reducing the calculation. However, traditional DBZP is very sensitive to bit transition and the misalignment of bit edge will cause serious power loss. To relieve the calculation load and acquire the weak signal successfully, an efficient BeiDou DBZP-based scheme is proposed. The proposed scheme is optimised in two aspects: the NH code phase searching and correlation integration. The step size of the proposed NH code searching method is half an NH code bit which means the number of searches in one navigation message bit is only 40 and the computation load can be reduced greatly. Additionally, the proposed inherited correlation integration establishes a tight inherited structure between adjoining coherent integrations which can reduce the calculation burden further. The experiment results show that the proposed scheme can acquire as weak as 22dBHz with only about 12% computation time of the traditional DBZP method.

关键词： satellite navigation signal detection modulation coding synchronisation phase coding search problems efficient BeiDou DBZP-based weak signal acquisition scheme software-defined receiver Neumann-Hoffman code data bit transition synchronisation double block zero padding method NH code phase searching method navigation

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Extending Distributed-Based Transversal Filter Method to Spectral Amplitude Encoded CDMA

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IEICE TRANSACTIONS ON ELECTRONICS 2018年第12期E101C卷 953-962页

作者： Aguilar-Torrentera, Jorge Garcia-Sanchez, Gerardo Rodriguez-Cruz, Ramon Darwazeh, Izzat Z. Univ Autonoma Nuevo Leon FIME San Nicolas De Los Garza 66450 Mexico UCL Dept Elect & Elect Engn Strong Commun & Informat Syst Grp 70 London England

In this paper, the analog code modulation characteristics of distributed-based transversal filters (DTFs) suitable for use in spectrally encoded CDMA systems are presented. The DTF is verified as an appropriate method to use in high-speed CDMA systems as opposed to previously proposed methods, which are intended for Direct Sequence (DS) CDMA systems. The large degree of freedom of DTF design permits controlling the filter pulse response to generate well specified temporal phase-coded signals. A decoder structure that performs bipolar detection of user subbands giving rise to a Spectral-Amplitude Encoded CDMA system is considered. Practical implementations require truncating the spreading signals by a time window of duration equal to the span time of the tapped delay line. Filter functions are chosen to demodulate the matched channel and achieve improved user interference rejection avoiding the need for transversal filters featuring a large number of taps. As a proof-of-concept of the electronic SAE scheme, practical circuit designs are developed at low speeds (3-dB point at 1 GHz) demonstrating the viability of the proposal.

关键词： code division multiplexing distributed amplifiers high-speed electronics modulation coding optical receivers

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Playback continuity and video quality driven optimisation for dynamic adaptive streaming over HTTP clients over wireless networks

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IET COMMUNICATIONS 2018年第10期12卷 1178-1187页

作者： He, Lijun Liu, Guizhong Huang, Xinyu Xi An Jiao Tong Univ Sch Elect & Informat Engn Xian 710049 Shaanxi Peoples R China

In this study, the authors focus on segment characteristic analysis and joint optimisation of modulation and coding scheme (MCS) selection, resource block (RB) assignment and the block error ratio (BLER) determination and segment adaptation scheme to satisfy dynamic adaptive streaming over HTTP (DASH) clients over wireless networks. First, the authors define a utility function as the continuous playback time that the packets scheduled with the allocated resource can support. Then, the authors formulate the MCS selection, RB assignment and BLER determination into a mathematical model. The relationship among the above three factors can be explored instead of performing MCS selection and RB assignment with the fixed BLER. By decomposing the original problem into some sub-problems, the authors can get a solution to the original problem with low complexity. At the client level, the authors develop an adaptive segment request strategy based on the playback information, the segments' characteristics and the estimated transmission rate. To decrease the influence of the inaccurate estimations, an adaptive guard time interval based on the real playback information and transmission information of the previous segments is introduced. Simulation results show that the proposed algorithm can efficiently improve playback continuity and video quality over the existing algorithms.

关键词： video streaming hypermedia radio networks modulation coding optimisation resource allocation playback continuity video quality driven optimisation dynamic adaptive streaming HTTP clients wireless networks segment characteristic analysis joint optimisation modulation and coding scheme selection MCS selection resource block assignment block error ratio determination segment adaptation scheme BLER determination utility function continuous playback time resource allocation RB assignment mathematical model adaptive segment request strategy playback information segment characteristics estimated transmission rate adaptive guard time interval transmission information

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Error-Correcting 56 modulation Code for Staggered Bit-Patterned Media Recording Systems

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IEEE MAGNETICS LETTERS 2019年 10卷

作者： Thien An Nguyen Lee, Jaejin Soongsil Univ Dept ICMC Convergence Technol Seoul 06978 South Korea

Bit-patterned media recording (BPMR) is a promising candidate for application in future magnetic recording systems. To achieve a high areal density in BPMR systems, the distance between bit islands is reduced. However, two-dimensional (2-D) interference may occur, including intersymbol interference in the down-track and intertrack interference in the cross track. The overall performance of BPMR is mainly limited by the emergence of 2-D interference in the readback signal. With the staggered-array layout, islands along the neighboring track are displaced by a half period from those on the main track. An island on the main track is primarily affected by the closest islands on the neighboring tracks. To overcome this problem, we introduce an error-correcting 56 modulation code that matches the structure of staggered-array bit-patterned media. The simulation results show that the system with the 5/6 modulation code achieves better performance.

关键词： modulation Encoding Gain Interference Decoding Media Simulation Information storage bit-patterned media recording error correcting modulation coding trellis modulation code

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Systematic Luby transform codes with modified grey-mapped QAM constellation

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ELECTRONICS LETTERS 2018年第12期54卷 766-767页

作者： Xu, Shengkai Xu, Dazhuan Nanjing Univ Aeronaut & Astronaut Coll Elect & Informat Engn Jiangsu Key Lab Internet Things & Control Technol Nanjing 211106 Jiangsu Peoples R China

Systematic Luby transform (LT) codes with grey-mapped QAM constellations over additive white Gaussian noise (AWGN) channels are investigated. For high-order modulations, it can be learnt that the traditional Gaussian approximation method developed for binary PSK (BPSK) is not accurate any more. To improve BER performance of systematic LT codes with grey-mapped QAM, therefore, presents a novel coded modulation scheme, which only extracts Gaussian alike log-likelihood ratios for decoding, based on the modified QAM constellation. More importantly, the proposed scheme allows to optimise degree distributions for QAM-modulated systematic LT codes as easily as for BPSK. Simulation results show that the degree distribution related to the proposed coded modulation scheme can provide outstanding BER performance for systematic LT codes over the AWGN channel.

关键词： approximation theory AWGN channels channel coding decoding Gaussian processes modulation coding phase shift keying quadrature amplitude modulation transform coding

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