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Source-Constrained hierarchical modulation Systems With Protograph LDPC Codes: A Promising Transceiver Design for Future 6G-Enabled IoT

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IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS 2025年第4期43卷 1103-1117页

作者： Yang, Zhaojie Li, Yunye Guan, Yong Liang Fang, Yi Nanyang Technol Univ Sch Elect & Elect Engn Singapore 639798 Singapore Guangdong Univ Technol Sch Informat Engn Guangzhou 510006 Peoples R China

This work studies the transceiver design and convergence performance analysis for the hierarchical modulation (HM) systems with protograph-based low-density parity-check (P-LDPC) codes. Specifically, we first conceive new source-constrained (SC) coding scheme and inter-layer-cascaded (ILC) decoding scheme tailored for the HM-based transmitter and receiver, respectively. Both the proposed SC coding and ILC decoding schemes form an enhanced version of bit-interleaved-coded HM (BIC-HM) systems, namely source-constrained HM (SC-HM) systems, providing a more reliable and flexible multi-data transmission solution. Moreover, according to the SC coding principle, we conceive a novel variable-node-degree-based (VND) multiplexing scheme to further improve the performance of the proposed SC-HM systems. Additionally, based on the ILC decoding framework, we devise a novel mutual information (MI) analysis tool, namely ILC-based extrinsic-information-transfer (ILC-EXIT) algorithm, to predict the decoding thresholds of the proposed P-LDPC-coded SC-HM systems. Theoretical and simulation results demonstrate that the proposed SC-HM systems significantly outperform the existing benchmarks in terms of error performance, decoding latency, and transmission-rate adaptation.

关键词： Streams Decoding Codes Encoding Multiplexing Quality of service Quadrature amplitude modulation Demodulation AWGN channels Transceivers Internet of Things hierarchical modulation bit-interleaved-coded modulation low-density parity-check codes transmission-rate adaptation

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hierarchical modulation-based cooperation utilizing relay-assistant full-duplex diversity

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WIRELESS NETWORKS 2011年第3期17卷 583-595页

作者： Son, Hyukmin Park, Jongrok Lee, Sanghoon Yonsei Univ Dept Elect & Elect Engn Seoul 120749 South Korea Yonsei Univ Wireless Network Lab Seoul 120749 South Korea

In this paper, we present a hierarchical modulation-based cooperation (HMC) scheme to overcome capacity degradation due to half-duplex transmissions in conventional cooperative relay systems. In the HMC scheme, two relay terminals are used for both transmit and receive operations, i.e., full-duplex transmission. This scheme reduces the required number of time slots for cooperation. Utilizing this cooperative mechanism, the HMC scheme achieves cooperative diversity at the destination node by combining the signals delivered from the source and relay nodes. In addition, we derive a closed form of the end-to-end bit error rate for the HMC scheme, which is utilized to determine an optimal power ratio for hierarchical signals at the source node. In concurrence with the HMC scheme, we develop the best relay selection scheme for a practical wireless communication networks.

关键词： hierarchical modulation Cooperative diversity Relay cooperation Full-duplex diversity

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hierarchical modulation for client-driven selective streaming of multi-view video over AWGN channels

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SIGNAL PROCESSING-IMAGE COMMUNICATION 2016年 47卷 152-159页

作者： You, Dongho Kim, Dong Ho Seoul Natl Univ Sci & Technol SeoulTech Grad Sch NID Fus Technol 232 Gongneung Ro Seoul 01811 South Korea

We consider a client-driven selective streaming system for multi-view video, which is supported by scalable multi-view video coding (SMVC). The system is used to reduce bit-rates for efficient transmission of multi-view video. The transmit source is partitioned into three layers: a base and two enhancement layers. The base layer contains all views encoded by MVC at a low-quality, while each enhancement layer contains high-quality part of the selected left and right views, respectively. The base layer is more important than the enhancement layers to create 3D perception, albeit of low-quality, and should be more protected than the enhancement layers. In this paper, two-level and three-level hierarchical 64QAM are used to provide unequal error protection (UEP) for the client-driven selective streaming system. First we find the suitable hierarchical values, which is the ratio of the distances in hierarchical 64QAM, for the client-driven selective streaming system. Furthermore, we analyze numerically how the hierarchical 64QAM impacts peak signal-to-noise ratio (PSNR) performance of fast and slow-motion sequences. Simulation results show that the three-level hierarchical 64QAM outperforms both conventional 64QAM with Gray mapping and the two-level hierarchical 64QAM in terms of achieving the target average PSNR performance at a low SNR environment. (C) 2016 Elsevier B.V. All rights reserved.

关键词： hierarchical modulation Unequal error protection Client-driven selective streaming Multi-view video Scalable multi-view video coding

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hierarchical modulation Based Spectrum Sharing in an Overlay Cognitive Radio Network 2

Hierarchical Modulation Based Spectrum Sharing in an Overlay...

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2nd International Conference on Devices for Integrated Circuit (DevIC)

作者： Mondal, Sukanta Banerjee, Partha Mukherjee, Rajesh Biswas, Arindam Pal, Anita Bhattacharjee, A. K. DIET Dept Comp Sci & Engn Murshidabad 742406 W Bengal India Acad Technol Dept ECE Durgapur W Bengal India NSHM Knowledge Campus Dept Comp Sci & Engn Durgapur W Bengal India NSHM Knowledge Campus Dept ECE Durgapur W Bengal India Natl Inst Technol Dept Math Durgapur W Bengal India Natl Inst Technol Acad Technol Dept ECE Durgapur W Bengal India

ISBN: (纸本)9781509047246

In this paper, we present a two phase cooperative relaying scheme for spectrum sharing in a 2 x 2 overlay cognitive radio. Secondary transmitter acts as decode and forward relay to the primary and employs hierarchical modulation to enhance primary SNR reception. Primary receiver employs cooperative maximal ratio combining to improve SNR and secondary receiver recovers its own data by successive interference cancellation. We have calculated symbol error rate (SER) analytically for such system and optimal power allocation factor between primary and secondary data in hierarchical modulation have been found out. The analytical result of SER is found close agreement with Monte-Carlo simulation

关键词： hierarchical modulation spectrum sharing decode and forward relaying cognitive radio

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hierarchical modulation with Vector Rotation for Multimedia Broadcasting

Hierarchical Modulation with Vector Rotation for Multimedia ...

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Globecom Workshops

作者： Zhao, Hui Zhou, Xiaoping Wang, Wenbo Beijing Univ Posts & Telecommun Key Lab Universal Wireless Commun Minist Educ Beijing 100088 Peoples R China

ISBN: (纸本)9781424488650

hierarchical modulation (HM) offers an important coverage/ throughput tradeoff for wireless communication, which involves a "base-layer" (BL) and an "enhancementlayer" (EL) bit streams. Generally, HM suffers from the severe performance degradation of the less protected EL stream. In this paper, HM with vector rotation operation introduced to EL stream is proposed, in order to improve the performance of EL stream. With the proper interleaving in frequency domain, this operation can exploit the inherent diversity gain from the frequency-selective channel. In this way, HM with vector rotation can effectively enhance video quality of multimedia broadcasting in wideband systems. In the experimental results with the assumption that scalable video coding (SVC) is taken at the source, the significant benefit in video quality is shown in comparison with the conventional HM and alternative schemes.

关键词： video broadcasting hierarchical modulation constellation rotation signal space diversity

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hierarchical modulation Symbol Sharing Scheme for Multiuser Cellular Networks 4

Hierarchical Modulation Symbol Sharing Scheme for Multiuser ...

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4th International Conference on Computer Science and Network Technology (ICCSNT)

作者： Ahn, Jinsoo Kim, Ronny Yongho Yonsei Univ Sch Elect & Elect Engn Seoul South Korea Korea Natl Univ Transporat Dept Railrd Elect & Elect Engn Uiwang South Korea

ISBN: (纸本)9781467381734

In this paper, a novel hierarchical modulation symbol sharing scheme for multiuser cellular networks is proposed. In order to achieve the maximum channel capacity, various modulation and coding schemes have been developed on Wireless Communication Systems. With good modulation and coding schemes, very high channel capacity could be achieved for 1-to-1 communication systems. Due to different channel conditions of multiple users, high channel capacity of multiple user network systems cannot be achieved with modulation and coding schemes used for 1-to1 communication technology. By exploiting the characteristics of multiple users in cell based multiuser networks, a novel hierarchical modulation symbol sharing scheme for cell based multiuser network systems is proposed. The proposed scheme not only achieves high network capacity but also substantially reduces channel access overhead for cell based multiuser systems. In the proposed symbol sharing scheme, multiple users are able to share one symbol by allocating bits in proper bit positions for each user. Since the proposed scheme allows to provide extra bits to its cell users, multiuser channel access delay could be substantially reduced. The simulation results corroborate the benefits of the proposed scheme. By exploiting the proposed scheme, very high network capacity of the next generation cell based multiuser networks can be achieved.

关键词： hierarchical modulation symbol sharing celluar network 802.11 quadrature amplitude modulation (QAM)

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Double-Layer Video Transmission Over Decode-and-Forward Wireless Relay Networks Using hierarchical modulation

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IEEE TRANSACTIONS ON IMAGE PROCESSING 2014年第4期23卷 1791-1804页

作者： Nguyen, Tu V. Cosman, Pamela C. Milstein, Laurence B. Broadcom Corp Mobile & Wireless Grp San Diego CA 92127 USA Univ Calif San Diego Dept Elect & Comp Engn San Diego CA 92093 USA

We consider a wireless relay network with a single source, a single destination, and a multiple relay. The relays are half-duplex and use the decode-and-forward protocol. The transmit source is a layered video bitstream, which can be partitioned into two layers, a base layer (BL) and an enhancement layer (EL), where the BL is more important than the EL in terms of the source distortion. The source broadcasts both layers to the relays and the destination using hierarchical 16-QAM. Each relay detects and transmits successfully decoded layers to the destination using either hierarchical 16-QAM or QPSK. The destination can thus receive multiple signals, each of which can include either only the BL or both the BL and the EL. We derive the optimal linear combining method at the destination, where the uncoded bit error rate is minimized. We also present a suboptimal combining method with a closed-form solution, which performs very close to the optimal. We use the proposed double-layer transmission scheme with our combining methods for transmitting layered video bitstreams. Numerical results show that the double-layer scheme can gain 2-2.5 dB in channel signal-to-noise ratio or 5-7 dB in video peak signal-to-noise ratio, compared with the classical single-layer scheme using conventional modulation.

关键词： Relay networks decode-and-forward relaying layered video transmission hierarchical modulation maximal ratio combining

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A robust symbol synchronization method for terrestrial-DMB receivers in the hierarchical modulation mode

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IEEE TRANSACTIONS ON CONSUMER ELECTRONICS 2008年第1期54卷 33-38页

作者： Kim, Joon Tae Kim, Yang Su Lim, Jong Soo Konkuk Univ Dept Elect Engn Seoul 143701 South Korea ETRI Taejon 305350 South Korea

Recently, hierarchical modulation has been considered as a way to increase the payload data in Terrestrial Digital Multimedia Broadcasting (T-DMB) transmission systems. This paper proposes a robust symbol synchronization method for T-DMB receivers working in the hierarchical modulation mode. The proposed method employs a timing error detector (TED) which produces a timing phase error at OFDM symbol rate instead of the frame rate. This method thus results in the robust synchronization of symbol timing in the presence of a Sampling Frequency Offset (SFO). Simulation results show that the proposed method outperforms the conventional one especially at a large SFO1.

关键词： symbol synchronization timing error detector T-DMB hierarchical modulation

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On hierarchical modulation for satellite broadcasting

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INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING 2018年第6期36卷 460-473页

作者： Kayhan, F. Montorsi, G. Taricco, G. Alagha, N. Univ Luxembourg Interdisciplinary Ctr Secur Reliabil & Trust SnT Luxembourg Luxembourg Politecn Torino Dept Elect & Telecommun Turin Italy European Space Technol Ctr ESA Estec Noordwijk Netherlands

This paper presents a comparative assessment of 2 multiplexing techniques for providing differentiated classes of services over a realistic broadcasting satellite channel under variable link conditions. A distinctive property of satellite broadcasting channels is the nonlinear characteristics of high power amplifier on-board of the satellite. Hence, the conventional additive white Gaussian noise channel with average power limitation is no longer an accurate model, and nonlinear characteristics have to be taken into account. In this paper, we compare the performance of time division multiplexing techniques combined with variable coding and modulation with that of hierarchical modulations delivering contents with 2 (or more) differentiated service qualities. The goal is to maximize the throughput over a given transponder while maintaining a target service availability. We design a practical transmitter scheme based on the hierarchical modulation and maximize the throughput by optimizing the achievable mutual information for finite size constellations. This optimization is done for additive white Gaussian noise channel with both average and peak power limit and will provide a lower bound on throughput, which can be achieved by nonorthogonal multiplexing scheme. The results indicate that the gains obtained by nonorthogonal multiplexing is significant only if the required signal to noise threshold for 2 services differ by more than 10dB. Finally, we provide the bit error ratio simulation results for some selected scenarios.

关键词： digital video broadcasting via satellite hierarchical modulation satellite broadcast channel

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Five Decades of hierarchical modulation and Its Benefits in Relay-Aided Networking

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IEEE ACCESS 2015年 3卷 2891-2921页

作者： Sun, Hua Dong, Chen Ng, Soon Xin Hanzo, Lajos Univ Southampton Sch Elect & Comp Sci Res Grp Commun Signal Proc & Control Southampton SO17 1BJ Hants England Univ Southampton Southampton SO17 1BJ Hants England Univ Southampton Sch Elect & Comp Sci Southampton SO17 1BJ Hants England

hierarchical modulation (HM), which is also known as layered modulation, has been widely adopted across the telecommunication industry. Its strict backward compatibility with single-layer modems and its low complexity facilitate the seamless upgrading of wireless communication services. The specific features of HM may be conveniently exploited for improving the throughput/information-rate of the system without requiring any extra bandwidth, while its complexity may even be lower than that of the equivalent system relying on conventional modulation schemes. As a recent research trend, the potential employment of HM in the context of cooperative communications has also attracted substantial research interests. Motivated by the lower complexity and higher flexibility of HM, we provide a comprehensive survey and conclude with a range of promising future research directions. Our contribution is the conception of a new cooperative communication paradigm relying on turbo trellis-coded modulation-aided twin-layer HM-16QAM and the analytical performance investigation of a four-node cooperative communication network employing a novel opportunistic routing algorithm. The specific performance characteristics evaluated include the distribution of delay, the outage probability, the transmit power of each node, the average packet power consumption, and the system throughput. The simulation results have demonstrated that when transmitting the packets formed by layered modulated symbol streams, our opportunistic routing algorithm is capable of reducing the transmit power required for each node in the network compared with that of the system using the traditional opportunistic routing algorithm. We have also illustrated that the minimum packet power consumption of our system using our opportunistic routing algorithm is also lower than that of the system using the traditional opportunistic routing algorithm.

关键词： hierarchical modulation coded modulation cooperative communication Ad Hoc network opportunistic routing

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