检索结果-内蒙古大学图书馆

Trainable Communication Systems: Concepts and Prototype

IEEE TRANSACTIONS ON COMMUNICATIONS 2020年第9期68卷 5489-5503页

作者： Cammerer, Sebastian Aoudia, Faycal Ait Doerner, Sebastian Stark, Maximilian Hoydis, Jakob ten Brink, Stephan Univ Stuttgart Inst Telecommun D-70659 Stuttgart Germany Nokia Bell Labs F-91620 Nozay France Hamburg Univ Technol Inst Commun D-21073 Hamburg Germany

We consider a trainable point-to-point communication system, where both transmitter and receiver are implemented as neural networks (NNs), and demonstrate that training on the bit-wise mutual information (BMI) allows seamless integration with practical bit-metric decoding (BMD) receivers, as well as joint optimization of constellation shaping and labeling. Moreover, we present a fully differentiable neural iterative demapping and decoding (IDD) structure which achieves significant gains on additive white Gaussian noise (AWGN) channels using a standard 802.11n low-density parity-check (LDPC) code. The strength of this approach is that it can be applied to arbitrary channels without any modifications. Going one step further, we show that careful code design can lead to further performance improvements. Lastly, we show the viability of the proposed system through implementation on software-defined radios (SDRs) and training of the end-to-end system on the actual wireless channel. Experimental results reveal that the proposed method enables significant gains compared to conventional techniques.

关键词： Receivers Training Optical transmitters Communication systems iterative decoding Optimization Autoencoder end-to-end learning iterative demapping and decoding code design geometric shaping software-defined radio

来源：评论

学校读者我要写书评

暂无评论

Benchmarking iterative Receivers for BICM Multi-Carrier Systems Against Capacity Bounds

引用

WIRELESS PERSONAL COMMUNICATIONS 2012年第3期63卷 713-729页

作者： Sand, Stephan Mensing, Christian Dammann, Armin German Aerosp Ctr DLR Inst Commun & Nav D-82234 Oberpfaffenhofen Wessling Germany

In this paper, we analyze iterative receivers for bit-interleaved coded modulation (BICM) multi-carrier systems and compare them against theoretical capacity bounds for the channel, coded modulation, and BICM. We map the theoretical capacity bounds into bit-error rate (BER) versus average signal-to-noise ratio per bit plots to simplify the comparison between the theoretical capacity bounds and simulated BER curves. As BER simulations show, iterative receivers with code doping or spreading reach the turbo-cliff within 1 or 0.3 dB of the independent Rayleigh fading channel capacity. While the iterative receiver with spreading is closer to the channel capacity than the one with code doping, the later one can eliminate the residual bit-errors after the turbo-cliff. We further present a combinatorial analysis of the distribution of the spread symbol constellation for Walsh-Hadamard spreading codes used in a BICM multi-carrier system to explain the above results.

关键词： OFDM Bit-interleaved coded modulation Code doping Differential encoding Spreading Walsh-Hadamard iterative demapping and decoding

来源：评论

学校读者我要写书评

暂无评论

Performance analysis for LDPC-coded modulation in MIMO multiple-access systems

引用

IEEE TRANSACTIONS ON COMMUNICATIONS 2007年第7期55卷 1417-1426页

作者： Wu, Jianming Lee, Heung-No Univ Pittsburgh Dept Elect & Comp Engn Pittsburgh PA 15261 USA

We consider a low-density parity-check (LDPC)-coded modulation scheme in multi-input multi-output (MIMO) multiple-access systems. The receiver can be regarded as a serially concatenated iterative detection and decoding scheme, where the LDPC decoders perform the role of outer decoder and the multiuser demapper does that of the inner decoder. In this paper, we investigate the performance of the scheme with simulation results and bounds. Union upper bounds are derived, which can be used as additional means to evaluate the performance of the MIMO multiple-access system.

关键词： iterative demapping and decoding low-density parity-check (LDPC)-coded modulation multi-input multi-output (MIMO) multiple-access system union upper bound

来源：评论

学校读者我要写书评

暂无评论

On LLR Clipping in BICM-IDD Non-Coherent MIMO Communications

引用

IEEE COMMUNICATIONS LETTERS 2011年第6期15卷 650-652页

作者： Gohary, Ramy H. Willink, Tricia J. Carleton Univ Dept Syst & Comp Engn Ottawa ON K1S 5B6 Canada Commun Res Ctr Terr Wireless Syst Ottawa ON K2H 8S2 Canada

In this letter a method is proposed for improving the performance of a BICM non-coherent MIMO communication system with iterative demapping and decoding. This method is based on adapting the clipping thresholds of the log-likelihood ratios of the demapper and the decoder to the channel realizations observed by each block. The method is particularly suited for systems in which the data blocks are relatively short and for systems in which list demapping is employed at the receiver.

关键词： Bit-interleaved coded-modulation iterative demapping and decoding non-coherent MIMO

来源：评论

学校读者我要写书评

暂无评论

Reduced-Complexity Noncoherent Soft-Decision-Aided DAPSK Dispensing With Channel Estimation

引用

IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY 2013年第6期62卷 2633-2643页

作者： Xu, Chao Liang, Dandan Ng, Soon Xin Hanzo, Lajos Univ Southampton Sch Elect & Comp Sci Southampton SO17 1BJ Hants England

Differential amplitude phase-shift keying (DAPSK), which is also known as star-shaped quadrature-amplitude modulation, has implementational advantages not only due to dispensing with channel estimation but as a benefit of its low signal detection complexity as well. It is widely recognized that separately detecting the amplitude and the phase of a received DAPSK symbol exhibits lower complexity than jointly detecting the two terms. However, since the amplitude and the phase of a DAPSK symbol are affected by correlated magnitude fading and phase rotations, detecting the two terms completely independently results in a performance loss, which is particularly significant for soft-decision-aided DAPSK detectors relying on multiple receive antennas. Therefore, in this contribution, we propose a new soft-decision-aided DAPSK detection method, which achieves optimum DAPSK detection capability at substantially reduced detection complexity. More specifically, we link each a priori soft-input bit to a specific part of the channel's output, so that only a reduced subset of the DAPSK constellation points has to be evaluated by the soft DAPSK detector. Our simulation results demonstrate that the proposed soft DAPSK detector exhibits lower detection complexity than that of independently detecting the amplitude and the phase, whereas the optimal performance of DAPSK detection is retained.

关键词： Differential amplitude phase-shift keying (DAPSK) iterative demapping and decoding Log-MAP Max-Log-MAP reduced complexity soft-decision-aided detection star quadrature-amplitude modulation (QAM)

来源：评论

学校读者我要写书评

暂无评论

On the Datacasting Scheme over Chinese DTTB Systems Using Signal Space Diversity

On the Datacasting Scheme over Chinese DTTB Systems Using Si...

引用

7th IEEE International Wireless Communications and Mobile Computing Conference (IWCMC)

作者： Wang, Xiaoqing Yang, Fang Wang, Jintao Tsinghua Univ Dept Elect Engn State Key Lab Microwave & Digital Commun Tsinghua Natl Lab Informat Sci & Technol TNList Beijing 100084 Peoples R China

ISBN: (纸本)9781424495375

To support the simultaneous transmission of multiple multimedia services with different quality of service (QoS) requirements within the same spectrum over digital television terrestrial broadcasting (DTTB) systems, datacasting approaches have been widely studied. In this paper, to improve the immunity to the fading in the mobile environment, a novel datacasting scheme for Chinese DTTB systems, namely digital television terrestrial multimedia broadcasting (DTMB), is proposed in a backward compatible manner. In this scheme, by taking advantage of the time-frequency domain physical sub-channel (PSC), the modulation method of the multi-dimensional rotated BPSK constellation mapping using the signal space diversity (SSD), which are backward compatible with DTMB systems, are addressed together with the iterative demapping and decoding technique. Simulations over Rayleigh channels show that the proposed scheme efficiently improves the mobile reception performance of newly-introduced services at acceptable complexity penalty meanwhile without any degradation in the existing DTMB receivers for terrestrial services.

关键词： Digital television terrestrial multimedia broadcasting (DTMB) datacasting multi-dimensional rotated constellation mapping physical sub-channel (PSC) iterative demapping and decoding

来源：评论

学校读者我要写书评

暂无评论

Turbo-decoding of a convolutionally encoded OCDMA system

Turbo-decoding of a convolutionally encoded OCDMA system

引用

Conference on Optical Transmission, Switching and Subsystems II

作者： Efinger, D Fritsch, R Univ Stuttgart Inst Telecommun D-70569 Stuttgart Germany

ISBN: (纸本)0819455792

We present a novel multiple access scheme for Passive Optical Networks (PON) based on optical Code Division Multiple Access (OCDMA). Different from existing proposals for implementing OCDMA, we replaced the predominating orthogonal or weakly correlated signature codes (e.g. Walsh-Hadamard codes (WHC)) by convolutional codes. Thus CDMA user separation and forward error correction (FEC) are combined. The transmission of the coded bits over the multiple access fiber is carried through optical BPSK. This requires electrical field strength detection rather than direct detection (DD) at the receiver end. Since orthogonality gets lost, we have to employ a multiuser receiver to overcome the inherently strong correlation. Computational complexity of multiuser detection is the major challenge and we show how complexity can be reduced by applying the turbo principle known from soft-decoding of concatenated codes. The convergence behavior of the iterative multiuser receiver is investigated by means of extrinsic information transfer charts (EXIT-chart). Finally, we present simulation results of bit error ratio (BER) vs. signal-to-noise ratio (SNR) including a standard single mode fiber in order to demonstrate the superior performance of the proposed scheme compared to those using orthogonal spreading techniques.

关键词： Optical Code Division Multiple Access (OCDMA) multiuser detection soft-in/soft-out decoding iterative demapping and decoding EXIT-chart

来源：评论

学校读者我要写书评

暂无评论

Mapping and Coding Design for Channel Coded Physical-layer Network Coding

Mapping and Coding Design for Channel Coded Physical-layer N...

引用

International Workshop on High Mobility Wireless Communications

作者： Li, Xu Zhang, Shengli Qian, Gongbin Shenzhen Univ Coll Informat Engn Dept Commun Engn Shenzhen Peoples R China

ISBN: (纸本)9781467363808;9781467363792

Although BTCM can significantly improves the BER performance by iteration processing between the demapping and the decoding in a traditional receiver, its design and performance in PNC system has fewer studied. This paper investigates a bit interleaved coded modulation (BICM) scheme in a Gaussian two-way relay channel operated with physical layer network coding (PNC). In particular, we first present an iterative demapping and decoding framework specially designed for PNC. After that, we compare different constellation mapping schemes in this framework, with the convergence analysis by using the EXIT chart. It is found that the anti-Gray mapping outperforms the Gray mapping, which is the best mapping in the traditional decoding schemes. Finally, the numerical simulation shows the better performance of our framework and verifies the mapping design.

关键词： Physical layer network coding iterative demapping and decoding BICM repeat accumulate code

来源：评论

学校读者我要写书评

暂无评论

Constellation Expansion: Theoretical Limits and Practical Examples

Constellation Expansion: Theoretical Limits and Practical Ex...

引用

16th International Conference on Transparent Optical Networks (ICTON)

作者： Leoni, Paolo Sleiffer, Vincent Calabro, Stefano Lankl, Berthold Univ Bundeswehr Munchen Inst Informat Tech Neubiberg Germany Eindhoven Univ Technol COBRA Inst Eindhoven Netherlands Coriant R&d GmbH Munich Germany

ISBN: (纸本)9781479956012

In optical communications the advent of coherent transmission techniques has been shortly followed by the breakthrough of soft decision (SD) forward error correction (FEC). The optical community put much effort into the design and implementation of powerful FEC codes. However, we show that, for the exemplary case of 100G polarization division multiplexed (PDM) systems, both with differential and non-differential transmission, a potential gain of more than 1 dB is still available if coding and modulation are jointly optimized. The benefits of this approach are characterized in terms of the capacity limits over a simplified channel model and are illustrated by means of practical examples and experimental results.

关键词： forward error correction constellation expansion channel capacity iterative demapping and decoding differential decoding coded modulation

来源：评论

学校读者我要写书评

暂无评论

Constellation Expansion: Theoretical Limits and Practical Examples

Constellation Expansion: Theoretical Limits and Practical Ex...

引用

International Conference on Transparent Optical Networks

作者： Paolo Leoni Vincent Sleiffer Stefano Calabro Berthold Lankl Institut fur Informationstechnik Universitat der Bundeswehr Munchen Neubiberg Germany COBRA Institute Eindhoven University of Technology Eindhoven the Netherlands Coriant R&D GmbH Munich Germany

ISBN: (纸本)9781479956029

关键词： forward error correction constellation expansion channel capacity iterative demapping and decoding differential decoding coded modulation

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：