Author: Gregory P. ChapellePublisher:
ISBN:
Category :
Languages : en
Pages : 280
Book Description
Continuous Phase Modulation for the Indoor Wireless Channel
Author: Gregory P. ChapelleChannel Effects on Continuous Phase Modulation
Author: Robert Goodyer HarknessPublisher:
ISBN:
Category : Modulation (Electronics)
Languages : en
Pages : 228
Book Description
Frequency Domain Processing Techniques for Continuous Phase Modulation
Author: Cheol Hee ParkPublisher:
ISBN:
Category :
Languages : en
Pages : 264
Book Description
The continuous phase modulation (CPM) has a constant envelope and compact output power spectrum that makes it a promising underlying technology for power and spectrum efficient broadband wireless communications. However, high implementation complexity (especially the complexity of the receiver) required to deal with the phase memory and inter-symbol interference has impeded its adoption for broadband wireless communications, and only a few simple CPM modulation schemes have mainly been used, e.g. binary MSK and GMSK. Thus, research on efficient CPM transceivers to reduce the computational and hardware complexity is important. The major contribution of this dissertation is the development of novel frequency domain processing techniques and transceiver strategies to improve power and spectral efficiency, and reduce the complexity of CPM modulation schemes. First, this dissertation presents simplified frequency domain receiver structures and decoding schemes in the frequency domain for binary and M-ary CPM block transmission. The frequency domain receivers utilize parallel and serial structures with frequency domain processing which considerably reduces hardware and computational complexity compared to conventional time-domain processing. In addition, the decoding schemes in the frequency domain eliminate the controlled phase memory through frequency domain phase equalization instead of maximum-likelihood sequential decoders, e.g. Viterbi decoders. Second, frequency domain channel estimation schemes for CPM block transmission are presented, which adopt superimposed training signals to achieve bandwidth and power efficiency while reducing the complexity. In these schemes, the proposed frequency domain channel estimation uses the superimposed training signals as a reference signal to reduce the throughput loss caused by conventionally multiplexed training signals. Superimposed training signal design is presented, and the trade-off between bandwidth efficiency and power efficiency is also analyzed. Third, block transmission schemes and frequency domain equalization methods for CPM are proposed, which consider linear processing instead of conventional decomposition-based processing. The schemes of frequency domain linear processing avoid the complexity overhead (both in computation and hardware) of conventional orthogonal- or Laurent decomposed-based equalizers. Finally, this dissertation extends CPM block transmission and frequency domain equalization to phase-coded (time-varying modulation index) CPM, which shows better error performance and bandwidth efficiency than fixed modulation index CPM's.
Digital Phase Modulation
Author: John B. AndersonPublisher: Springer Science & Business Media
ISBN: 1489920315
Category : Technology & Engineering
Languages : en
Pages : 509
Book Description
The last ten years have seen a great flowering of the theory of digital data modulation. This book is a treatise on digital modulation theory, with an emphasis on these more recent innovations. It has its origins in a collabor ation among the authors that began in 1977. At that time it seemed odd to us that the subjects of error-correcting codes and data modulation were so separated; it seemed also that not enough understanding underlay the mostly ad hoc approaches to data transmission. A great many others were intrigued, too, and the result was a large body of new work that makes up most of this book. Now the older disciplines of detection theory and coding theory have been generalized and applied to the point where it is hard to tell where these end and the theories of signal design and modulation begin. Despite our emphasis on the events of the last ten years, we have included all the traditional topics of digital phase modulation. Signal space concepts are developed, as are simple phase-shift-keyed and pulse-shaped modulations; receiver structures are discussed, from the simple linear receiver to the Viterbi algorithm; the effects of channel filtering and of hardlimiting are described. The volume thus serves well as a pedagogical book for research engineers in industry and second-year graduate students in communications engineering. The production of a manageable book required that many topics be left out.
Space-time Continuous Phase Modulation
Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
The combination of Space-Time (ST) coding and Continuous-Phase Modulation (CPM) produces a low power, energy efficient communication scheme suitable for wireless transmission. Space-time coding increases the reliability of transmission, and continuous-phase modulation (CPM) has the potential to provide considerable energy savings. CPM is a modulation technique that involves the transmission of a signal with continuous-phase and a constant envelope, where the continuous-phase property produces a very bandwidth efficient signal, and the constant-envelope property enables non linear (and thus energy efficient) signal amplification. The ST-CPM code is of special interest for wireless sensors because in the wireless sensor network environment energy consumption is highly constrained. The combination of ST codes and CPM is non-trivial and thus ST-CPM codes based upon block-based orthogonal and diagonal signal matrices are presented. These codes are forms the basis of a distributed ST-CPM code. The distributed ST codes are designed to operate in wireless networks containing a large set of nodes, of which only a small a priori unknown subset will be active at any time. The devised distributed ST-CPM scheme combines the ST-CPM code with a diagonal signaling matrix, (commonly assigned to all relay nodes) with signature vectors(uniquely assigned to nodes). The energy consumption of the proposed distributed ST-CPM scheme is compared with that of a distributed ST linear modulation (LM) scheme. The distributed ST-CPM scheme is shown to outperform the distributed ST-LM scheme for all but short-range transmission. Finally, a serially concatenated code for ST-CPM is proposed. The concatenated code consists of the diagonal signalling matrix as the inner code, and a class of double parity check (DPC) codes as the outer code. The resulting concatenated codes that are formed from the ST-CPM code and a DPC code are shown to provide performance close to capacity, and to provide performanc.
Continuous Phase Modulation for High Speed Fiber-optic Links
Author: Thomas Frederick DetwilerPublisher:
ISBN:
Category : Fiber optics
Languages : en
Pages :
Book Description
Fiber-optic networks are continually evolving to accommodate the ever increasing data rates demanded by modern applications and devices. The current state-of-the art systems are being deployed with 100 Gb/s rates per wavelength while maintaining the 50 GHz channel spacing established for 10 Gb/s dense wavelength division multiplexed (DWDM) systems. Phase modulation formats (in particular quadrature phase shift keying - QPSK) are necessary to meet the spectral efficiency (SE) requirements of the application. The main challenge for phase modulated optical systems is fiber nonlinearities, where changes in intensity of the combined optical signal result in changes to the fiber's refractive index. Limiting launch power is the primary means to avoid dramatic intensity fluctuations, a strategy which in turn limits the available signal-to-noise ratio (SNR) within the channel. : Continuous phase modulation (CPM) is a format in which data is encoded in the phase, while the amplitude is constant throughout all transmission (even during transitions between symbols). With the goal of reducing the impact of nonlinearities, the purpose of this research was to identify a set of CPM signals best suited for high speed fiber-optic transmission, and quantify their performance against other formats. The secondary goal was to identify techniques appropriate for demodulation of high speed fiber-optic systems and implement them for simulation and experimental research.
Timing Recovery for Continuous Phase Modulation Transmitted Over Fast Flat-fading Channels
Author: François PatenaudePublisher:
ISBN:
Category : Phase modulation
Languages : en
Pages : 0
Book Description
The problem of deriving symbol synchronization information from the received signal for a class of bandwidth efficient continuous phase modulation (CPM) schemes transmitted over a fast flat-fading channel is studied. The modulation class considered is M-ary CPM with a modulation index h = 1/M. A particular synchronizer structure which generates a tone at the symbol rate in a manner which automatically cancels the fading phase effects is proposed and analyzed in detail. The practical aspects of implementing this synchronizer using digital signal processing methods are discussed. Finally, simulation results showing the root mean square jitter produced by this synchronizer for a few well-known cases of modulation and fading channel parameters are presented to illustrate the performances of the system.
Advanced Synchronization Techniques for Continuous Phase Modulation
Author: Qing ZhaoPublisher:
ISBN:
Category : Iterative methods (Mathematics)
Languages : en
Pages :
Book Description
The objective of this research work is to develop reliable and power-efficient synchronization algorithms for continuous phase modulation (CPM). CPM is a bandwidth and power efficient signaling scheme suitable for wireless and mobile communications. Binary CPM schemes have been widely used in many commercial and military systems. CPM with multilevel symbol inputs, i.e., M-ary CPM, can achieve a higher data rate than binary CPM. However, the use of M-ary CPM has been limited due to receiver complexity and synchronization problems. In the last decade, serially concatenated CPM (SCCPM) has drawn more attention since this turbo-like coded scheme can achieve near Shannon-limit performance by performing iterative demodulation/decoding. Note that SCCPM typically operates at a low signal-to-noise ratio, which makes reliable and power-efficient synchronization more challenging. In this thesis, we propose a novel timing and phase recovery technique for CPM. Compared to existing maximum-likelihood estimators, the proposed data-aided synchronizer can achieve a better acquisition performance when a preamble is short or channel model errors are present. We also propose a novel adaptive soft-input soft-output (A-SISO) module for iterative detection with parameter uncertainty. In contrast to the existing A-SISO algorithms using linear prediction, the parameter estimation in the proposed structure is performed in a more general least-squares sense. Based on this scheme, a family of fixed-interval A-SISO algorithms are utilized to implement blind iterative phase synchronization for SCCPM. Moreover, the convergence characteristics of iterative phase synchronization and detection are analyzed by means of density evolution. Particularly, an oscillatory convergence behavior is observed when cycle slips occur during phase tracking. In order to reduce performance degradation due to this convergence fluctuation, design issues, including delay depth of the proposed algorithms, iteration-stopping criteria and interleaver size, are also discussed. Finally, for completeness of the study on phase synchronization, we investigate the error probability performance of noncoherently detected full-response CPM, which does not require channel (or phase) estimation.
Radio over Fiber for Wireless Communications
Author: Xavier N. FernandoPublisher: John Wiley & Sons
ISBN: 1118797035
Category : Technology & Engineering
Languages : en
Pages : 335
Book Description
A comprehensive evaluation of Fi-Wi, enabling readers to design links using channel estimation and equalization algorithms This book provides a detailed study of radio over fiber (ROF) based wireless communication systems, otherwise called fiber wireless (Fi-Wi) systems. This is an emerging hot topic where the abundant bandwidth of optical fiber is directly combined with the flexibility and mobility of wireless networks to provide broadband connectivity. Its application is increasing because of the growing demand for broadband wireless services. In such a system the transmission of the radio signals over a fiber is an important task. This book provides substantial material on the radio over fiber part of the complete fiber-wireless system, including new research results on the compensation methods. The early chapters provide fundamental knowledge required for a non-expert engineering professional as well as senior/graduate level students to learn this topic from scratch. The latter part of the book covers advanced topics useful for researchers and senior students. Therefore, this book provides a comprehensive understanding of the system for readers who will gain enough knowledge to design Fi-Wi links of their own by learning how to develop Fi-Wi channel estimation and equalization algorithms. This concept is completely novel in current literature and has been patented by the author. Readers are expected to have a basic understanding of fiber optics and wireless communications to easily follow the book and to appreciate the concepts. Basics of the Fi-Wi system and signal processing approaches are clearly explained. It covers a multidisciplinary topic and acts as a bridge between optical and wireless communication domains. In the increasingly demanding telecommunications profession, engineers are expected to have knowledge in both optical and wireless communications and expected design combined/hybrid systems. Hence, the book is written in such a way that both optical and wireless professionals will be able to easily understand and perceive the concepts. follows a logical process from basic principles through to advanced topics, providing a wide range of interest for researchers, practicing engineers, students, and those required to build such networks explains detailed system design concepts and the limitations and advantages in each configuration, appealing to design engineers, and largely avoiding system specifics demonstrates the author’s exclusive patent, showing how to develop baseband signal processing algorithms for Fi-Wi systems, which is a key requirement for the successful deployment of Fi-Wi systems contains tables, numerical examples and case studies, facilitating a good quantitative understanding of the topic
Constant Envelope OFDM Phase Modulation
Author: Steve Charles ThompsonPublisher:
ISBN:
Category :
Languages : en
Pages : 430
Book Description