Frequency spectrum is a limited and valuable resource for wireless communications. A good example can be observed among network operators in Europe for the prices to pay for UMTS-frequency bands. Therefore, the first goal when designing future wireless communication systems (e.g. 4G - fourth generation) has to be the increase in spectral efficiency. The development in digital communications in the past years has enabled efficient modulation and coding techniques for robust and spectral efficient data, speech, audio and video transmission. These are the multi-carrier modulation (e.g. OFDM) and the spread spectrum technique (e.g. DS-CDMA), where OFDM was chosen for broadcast applications (DVB, DAB) as well as for broadband wireless indoor standards (ETSI HIPERLAN-II, IEEE-802.11) and the DS-CDMA was selected in mobile communications (IS-95, third generation mobile radio systems world wide, UMTS/IMT 2000). Since 1993 various combinations of multi-carrier (MC) modulation and the spread spectrum (SS) technique have been introduced and the field of MC-SS communications has become an independent and important research topic with increasing activities. New application fields have been proposed such as high rate cellular mobile, high rate wireless indoor and LMDS. It has been shown that MC-SS offers the high spectral efficiency, robustness and flexibility that is required for the next generation systems. Meanwhile, different alternative hybrid schemes such as OFDM/OFDMA, MC-TDMA, etc. have been deeply analysed and adopted in different international standards (ETSI-BRAN, IEEE-802 & MMAC). Multi-Carrier & Spread-Spectrum: Analysis of Hybrid Air Interfaces draws together all of the above mentioned hybrid schemes therefore providing a greatly needed resource for system engineers, telecommunication designers and researchers in order to enable them to develop, build and deploy several schemes based on MC-transmission for the next generation systems (which will be an integration of broadband multimedia services covering both 4G mobile and fixed wireless systems). * Offers a complete treatment of multi-carrier, spread-spectrum (SS) and time division multiplexing (TDM) techniques * Provides an in-depth insight into hybrid multiple access techniques based on multi-carrier (MC) transmission * Presents numerous hybrid multiple access and air interface architectures including OFDM/CDMA, MC-CDMA, MC-DS-CDMA and MT-CDMA * Covers new techniques such as space-time coding and software radio Telecommunications engineers, hardware & software system designers and researchers as well as students, lecturers and technicians will all find this an invaluable addition to their bookshelf.

The benefits and success of multi-carrier (MC) modulation on one side and the flexibility offered by the spread spectrum (SS) technique on the other side have motivated many researchers to investigate the combination of both techniques since 1993. This combination known as multi-carrier spread spectrum (MC-SS) benefits from the advantages of both systems and offers high flexibility, high spectral efficiency, simple detection strategies, narrow-band interference rejection capability, etc. The basic principle of this combination is straightforward: The spreading is performed as direct sequence spread spectrum (DS-SS) but instead of transmitting the chips over a single carrier, several sub-carriers are employed. The MC modulation and demodulation can easily be realized in the digital domain by performing IFFT and FFT operations. The separation of the users’ signals can be performed in the code domain. MC-SS systems can perform the spreading in frequency direction, which allows for simple signal detection strategies. Since 1993, MC-SS has been deeply studied and new alternative solutions have been proposed. Meanwhile, deep system analysis and comparison with DS-CDMA have been performed that show the superiority of MC-CDMA. The aim of Multi-Carrier Spread-Spectrum is to edit the ensemble of the newest contributions and research results in this new field that have been presented during the 5th International Workshop on Multi-Carrier Spread-Spectrum (MC-SS 2005), held in Oberpfaffenhofen, Germany.

The technological progress in multi-carrier (MC) modulation led orthogonal frequency division multiplexing (OFDM) to become an important part of beyond 3G cellular mobile communication standards, including LTE and WiMAX. In addition, the flexibility offered by the spread spectrum (SS) and time division multiplexing (TDM) techniques motivated many researchers to investigate several MC combined multiple access schemes, such as MC-CDMA, OFDMA and MC-TDMA. These schemes benefit from the advantages of each sub-system and offer high flexibility, high spectral efficiency, simple detection strategies and narrow-band interference rejection capability. Multi-Carrier and Spread Spectrum Systems is one of the first books to describe and analyze the basic concepts of multi-carrier OFDM transmission and its combination with spread spectrum (MC-CDMA). The different architectures and detection strategies as well as baseband-related transceiver components are explained. This includes topics like FEC channel coding and decoding, modulation and demodulation (IFFT/FFT), digital I/Q-generation, time and frequency synchronisation, channel estimation, frequency domain equalization and RF aspects such as phase noise and non-linearity issues. Concrete examples of its applications for cellular mobile communication systems (B3G/4G) are given. Further derivatives of MC-SS (such as OFDMA, SS-MC-MA and DFT-spread OFDM) and their corresponding applications in the LTE, WiMAX, WLAN and DVB-RCT standards are detailed. Capacity and flexibility enhancements of multi-carrier OFDM systems by different MIMO diversity techniques such as space time/frequency coding (STC, SFC) and software defined radio concepts are also described. Written in a highly accessible manner this book provides a unique reference on the topics of multi-carrier and spread spectrum communications, assisting 4G engineers with their implementation. Fully updated new edition of successful text, including two new chapters on LTE and WiMAX Describes in detail new applications of OFDM in mobile communication standards Examines all multi-carrier spread spectrum schemes, with in-depth analysis, from theory to practice Introduces the essentials of important wireless standards based on multi-carrier/spread spectrum techniques.

Spread spectrum and CDMA are cutting-edge technologies widely used in operational radar, navigation and telecommunication systems and play a pivotal role in the development of the forthcoming generations of systems and networks. This comprehensive resource presents the spread spectrum concept as a product of the advancements in wireless IT, shows how and when the classical problems of signal transmission/processing stimulate the application of spread spectrum, and clarifies the advantages of spread spectrum philosophy. Detailed coverage is provided of the tools and instruments for designing spread spectrum and CDMA signals answering why a designer will prefer one solution over another. The approach adopted is wide-ranging, covering issues that apply to both data transmission and data collection systems such as telecommunications, radar, and navigation. Presents a theory-based analysis complemented by practical examples and real world case studies resulting in a self-sufficient treatment of the subject Contains detailed discussions of new trends in spread spectrum technology such as multi-user reception, multicarrier modulation, OFDM, MIMO and space-time coding Provides advice on designing discrete spread spectrum signals and signal sets for time-frequency measuring, synchronization and multi-user communications Features numerous Matlab-based problems and other exercises to encourage the reader to initiate independent investigations and simulations This valuable text provides timely guidance on the current status and future potential of spread spectrum and CDMA and is an invaluable resource for senior undergraduates and postgraduate students, lecturers and practising engineers and researchers involved in the deployment and development of spread spectrum and CDMA technology. Supported by a Companion website on which instructors and lecturers can find a solutions manual for the problems and Matlab programming, electronic versions of some of the figures and other useful resources such as a list of abbreviations.

Perspectives in Spread Spectrum brings together studies and recent work on six exciting topics from the spread spectrum arts. The book gives a wide, collective view of trends, ideas, and techniques in the spread spectrum discipline, due to the authors' extensive work on spread spectrum techniques and applications from different vantage points. The inexorable march of electronics towards ever faster, ever smaller, and ever more powerful electronic and optical circuitry has wrought, and will continue to enable, profound changes in the spread spectrum arts, by allowing increasingly complex signalling waveforms and statistical tests to be implemented as the theory beyond spread spectrum continues to evolve. Perspectives in Spread Spectrum is divided into six chapters. The first chapter deals with sequence spreading design. There is not a single metric for design of spreading sequences; rather, the design is ideally tailored to the specific scenario of usage. This chapter delves into recent and very promising synthesis work. The second chapter deals with OFDM techniques. As channels become wider and trans-channel fading (or jamming) becomes frequency selective across the band, OFDM techniques may provide a powerful alternative design perspective. The third chapter is a generalization of the venerable Walsh functions. A new modulation scheme, Geometric Harmonic Modulation, GHM for short, is reviewed and characterized as a form of OFDM. From GHM, a further generalization of the Walsh functions is derived for non-binary signalling. The fourth chapter is concerned with some new and exciting results regarding the follower jammer paradigm. A counter-countermeasure technique is reviewed, notable for its counterintuitive characteristic which can be understood from a simple yet elegant game framework. The fifth chapter recounts some results pertaining to random coding for an optical spread spectrum link. The technique is based on laser speckle statistics and uses a coherent array of spatial light modulators at the transmitter but allows the receiver to be realized as a spatially distributed radiometric and therefore incoherent structure. The sixth and final chapter looks at an important and interesting application of spread spectrum to accurately locate a wideband, ‘bent pipe’, satellite transponder. It is, in a strong sense, an inverted GPS technique. Perspectives in Spread Spectrum serves as an excellent reference and source of ideas for further research, and may be used as a text for advanced courses on the topic.

This book provides the proceedings of the 6th International Workshop on Multi-Carrier Spread Spectrum (MC-SS 2007), 7-9 May 2007, held in Herrsching, Germany. The book aims to edit the ensemble of the newest contributions and research results in this new field. The book presents comprehensive state-of-the-art articles about multi-carrier spread spectrum techniques, and discusses multi-carrier spread spectrum techniques.

This book provides the proceedings of the 6th International Workshop on Multi-Carrier Spread Spectrum (MC-SS 2007), 7-9 May 2007, held in Herrsching, Germany. The book aims to edit the ensemble of the newest contributions and research results in this new field. The book presents comprehensive state-of-the-art articles about multi-carrier spread spectrum techniques, and discusses multi-carrier spread spectrum techniques.

Khaled Fazel Stefan Kaiser Digital Microwave Systems German Aerospace Center (DLR) Bosch Telecom GmbH Institute for Communications Technology D-71522 Backnang, Germany D-82234 Wessling, Germany In this last decade of this millennium the technique of multi-carrier transmission for wireless broadband multimedia applications has been receiving wide interests. Its first great success was in 1990 as it was selected in the European Digital Audio Broadcasting (DAB) standard. Its further prominent successes were in 1995 and 1998 as it was selected as modulation scheme in the European Digital Video Broadcasting (DVB-T) and in three broadband wireless indoor standards, namely ETSI-Hiperlan-II, American IEEE-802. 11 and Japanese MMAC, respectively. The benefits and success of multi-carrier (MC) modulation in one side and the flexibility offered by spread spectrum (SS) technique in other hand motivated many researchers to investigate the combination of both techniques, known as multi-carrier spread-spectrum (MC-SS). This combination benefits from the main advantages of both systems and offers high flexibility, high spectral efficiency, simple detection strategies, narrow band interference rejection capability, etc. . The basic principle of this combination is straightforward: The spreading is performed as direct SS (DS-SS) but instead of transmitting the chips over a single sequence carrier, several sub-carriers could be employed. As depicted in Figure 1, after spreading with assigned user specific code of processing gain G the frequency mapping and multi-carrier modulation is applied. In the receiver side after multi-carrier demodulation and frequency de-mapping, the corresponding detection algorithm will be performed.

This textbook takes a unified view of the fundamentals of wireless communication and explains cutting-edge concepts in a simple and intuitive way. An abundant supply of exercises make it ideal for graduate courses in electrical and computer engineering and it will also be of great interest to practising engineers.