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Analog transmission

About: Analog transmission is a research topic. Over the lifetime, 8068 publications have been published within this topic receiving 101185 citations. The topic is also known as: analogue transmission.


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Book
01 Jan 1994
TL;DR: This book discusses Elements of an Electrical Communication System, a manual for the design of Communication Channels and their Characteristics, and Random Processes: Basic Concepts, which describes random processes in the Frequency Domain.
Abstract: (NOTE: Each chapter concludes with Further Reading and Problems.) 1. Introduction. Historical Review. Elements of an Electrical Communication System. Communication Channels and Their Characteristics. Mathematical Models for Communication Channels. Organization of the Book. 2. Frequency Domain Analysis of Signals and Systems. Fourier Series. Fourier Transforms. Power and Energy. Sampling of Bandlimited Signals. Bandpass Signals. 3. Analog Signal Transmission and Reception. Introduction to Modulation. Amplitude Modulation (AM). Angle Modulation. Radio and Television Broadcasting. Mobile Radio Stations. 4. Random Processes. Probability and Random Variables. Random Processes: Basic Concepts. Random Processes in the Frequency Domain. Gaussian and White Processes. Bandlimited Processes and Sampling. Bandpass Processes. 5. Effect of Noise on Analog Communication Systems. Effect of Noise on Linear-Modulation Systems. Carrier-Phase Estimation with a Phase-Locked Loop (PLL). Effect of Noise on Angle Modulation. Comparison of Analog-Modulation Systems. Effects of Transmission Losses and Noise in Analog Communication Systems. 6. Information Sources and Source Coding. Modeling of Information Sources. Source-Coding Theorem. Source-Coding Algorithms. Rate-Distortion Theory. Quantization. Waveform Coding. Analysis-Synthesis Techniques. Digital Audio Transmission and Digital Audio Recording. The JPEG Image-Coding Standard. 7. Digital Transmission through the Additive White Gaussian Noise Channel. Geometric Representation of Signal Waveforms. Pulse Amplitude Modulation. Two-Dimensional Signal Waveforms. Multidimensional Signal Waveforms. Optimum Receiver for Digitally Modulated Signals in Additive White Gaussian Noise. Probability of Error for Signal Detection in Additive White Gaussian Noise. Performance Analysis for Wireline and Radio Communication Channels. Symbol Synchronization. 8. Digital Transmission through Bandlimited AWGN Channels. Digital Transmission through Bandlimited Channels. The Power Spectrum of Digitally Modulated Signals. Signal Design for Bandlimited Channels. Probability of Error in Detection of Digital PAM. Digitally Modulated Signals with Memory. System Design in the Presence of Channel Distortion. Multicarrier Modulation and OFDM. 9. Channel Capacity and Coding. Modeling of Communication Channels. Channel Capacity. Bounds on Communication. Coding for Reliable Communication. Linear Block Codes. Cyclic Codes. Convolutional Codes. Complex Codes Based on Combination of Simple Codes. Coding for Bandwidth-Constrained Channels. Practical Applications of Coding. 10. Wireless Communications. Digital Transmission on Fading Multipath Channels. Continuous Carrier-Phase Modulation. Spread-Spectrum Communication Systems. Digital Cellular Communication Systems. Appendix A: The Probability of Error for Multichannel Reception of Binary Signals. References. Index.

1,029 citations

Journal ArticleDOI
G. Ungerboeck1
TL;DR: An introduction into TCM is given, reasons for the development of TCM are reviewed, and examples of simple TCM schemes are discussed.
Abstract: rellis-Coded Modulation (TCM) has evolved over the past decade as a combined coding and modulation technique for digital transmission over band-limited channels. Its main attraction comes from the fact that it allows the achievement of significant coding gains over conventional uncoded multilevel modulation without compromising bandwidth efficiency. T h e first TCM schemes were proposed in 1976 [I]. Following a more detailed publication [2] in 1982, an explosion of research and actual implementations of TCM took place, to the point where today there is a good understanding of the theory and capabilities of TCM methods. In Part 1 of this two-part article, an introduction into TCM is given. T h e reasons for the development of TCM are reviewed, and examples of simple TCM schemes are discussed. Part I1 [I51 provides further insight into code design and performance, and addresses. recent advances in TCM. TCM schemes employ redundant nonbinary modulation in combination with a finite-state encoder which governs the selection of modulation signals to generate coded signal sequences. In the receiver, the noisy signals are decoded by a soft-decision maximum-likelihood sequence decoder. Simple four-state TCM schemes can improve. the robustness of digital transmission against additive noise by 3 dB, compared to conventional , uncoded modulation. With more complex TCM schemes, the coding gain can reach 6 dB or more. These gains are obtained without bandwidth expansion or reduction of the effective information rate as required by traditional error-correction schemes. Shannon's information theory predicted the existence of coded modulation schemes with these characteristics more than three decades ago. T h e development of effective TCM techniques and today's signal-processing technology now allow these ,gains to be obtained in practice. Signal waveforms representing information sequences ~ are most impervious to noise-induced detection errors if they are very different from each other. Mathematically, this translates into therequirement that signal sequences should have large distance in Euclidean signal space. ~ T h e essential new concept of TCM that led to the afore-1 mentioned gains was to use signal-set expansion to I provide redundancy for coding, and to design coding and ' signal-mapping functions jointly so as to maximize ~ directly the \" free distance \" (minimum Euclidean distance) between coded signal sequences. This allowed the construction of modulation codes whose free distance significantly exceeded the minimum distance between uncoded modulation signals, at the same information rate, bandwidth, and signal power. The term \" …

874 citations

Journal ArticleDOI
TL;DR: Although the TMTFs are not directly consistent with the attenuation characteristic of a simple lowpass filter, a model which incorporates such a filter, with a time constant of 2.5 ms, describes the entire TMTF and also describes the modulation functions obtained with square-wave and pulse modulation.
Abstract: The detectability of amplitude modulation in the absence of spectral cues provides a quantitative description of temporal resolution for steady‐state signals with relatively small amplitude changes. Modulation thresholds for sinusoidally amplitude‐modulated wideband noise were measured as a function of modulation frequency. The resulting ’’Temporal Modulation Transfer Function’’ (TMTF) shows a lowpass characteristic for modulation frequencies below about 800 Hz. The lowpass characteristic is extended up to approximately 2 kHz when the increment in average power produced by modulation is eliminated. The important parametric effects are summarized as follows: (1) TMTFs are independent of overall level, except at very low intensities; (2) the time constant indicated by the TMTF decreases as the center frequency of the band‐limited, modulated noise is increased; (3) modulation thresholds generally decrease with increasing duration of modulation, particularly at low modulation frequencies; (4) when the carrier is gated for the duration of modulation, the TMTF shows a highpass segment at low modulation frequencies. Although the TMTFs are not directly consistent with the attenuation characteristic of a simple lowpass filter, a model which incorporates such a filter, with a time constant of 2.5 ms, describes the entire TMTF and also describes the modulation functions obtained with square‐wave and pulse modulation. The wide bandwidth of initial filtering indicated by the model raises the important question of the role of peripheral filtering in determining the detectability of high‐frequency modulation.

719 citations

Journal ArticleDOI
TL;DR: The history of research and development related to coherent optical communications is reviewed and the principle of coherent detection is described, including its quantum-noise characteristics, which discusses the role of digital signal processing in mitigating linear transmission impairments, estimating the carrier phase, and tracking the state of polarization of the signal in coherent receivers.
Abstract: The recently developed digital coherent receiver enables us to employ a variety of spectrally efficient modulation formats such as $M$ -ary phase-shift keying and quadrature-amplitude modulation. Moreover, in the digital domain, we can equalize all linear transmission impairments such as group-velocity dispersion and polarization-mode dispersion of transmission fibers, because coherent detection preserves the phase information of the optical signal. This paper reviews the history of research and development related to coherent optical communications and describes the principle of coherent detection, including its quantum-noise characteristics. In addition, it discusses the role of digital signal processing in mitigating linear transmission impairments, estimating the carrier phase, and tracking the state of polarization of the signal in coherent receivers.

618 citations

Journal ArticleDOI
TL;DR: A transmission system with adjustable data rate for single-carrier coherent optical transmission is proposed, which enables high-speed transmission close to the Shannon limit, and it is experimentally demonstrated that the optical transmission of probabilistically shaped 64-QAM signals outperforms the transmission reach of regular 16- QAM and regular 64-ZAM signals.
Abstract: A transmission system with adjustable data rate for single-carrier coherent optical transmission is proposed, which enables high-speed transmission close to the Shannon limit. The proposed system is based on probabilistically shaped 64-QAM modulation formats. Adjustable shaping is combined with a fixed-QAM modulation and a fixed forward-error correction code to realize a system with adjustable net data rate that can operate over a large reach range. At the transmitter, an adjustable distribution matcher performs the shaping. At the receiver, an inverse distribution matcher is used. Probabilistic shaping is implemented into a coherent optical transmission system for 64-QAM at 32 Gbaud to realize adjustable operation modes for net data rates ranging from 200 to 300 Gb/s. It is experimentally demonstrated that the optical transmission of probabilistically shaped 64-QAM signals outperforms the transmission reach of regular 16-QAM and regular 64-QAM signals by more than 40% in the transmission reach.

564 citations


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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
202314
202231
202113
202014
201912
201826