Millimeter-wave (mmW) frequencies between 30 and 300 GHz are a new frontier for cellular communication that offers the promise of orders of magnitude greater bandwidths combined with further gains via beamforming and spatial multiplexing from multielement antenna arrays. This paper surveys measurements and capacity studies to assess this technology with a focus on small cell deployments in urban environments. The conclusions are extremely encouraging; measurements in New York City at 28 and 73 GHz demonstrate that, even in an urban canyon environment, significant non-line-of-sight (NLOS) outdoor, street-level coverage is possible up to approximately 200 m from a potential low-power microcell or picocell base station. In addition, based on statistical channel models from these measurements, it is shown that mmW systems can offer more than an order of magnitude increase in capacity over current state-of-the-art 4G cellular networks at current cell densities. Cellular systems, however, will need to be significantly redesigned to fully achieve these gains. Specifically, the requirement of highly directional and adaptive transmissions, directional isolation between links, and significant possibilities of outage have strong implications on multiple access, channel structure, synchronization, and receiver design. To address these challenges, the paper discusses how various technologies including adaptive beamforming, multihop relaying, heterogeneous network architectures, and carrier aggregation can be leveraged in the mmW context.

Millimeter-Wave Cellular Wireless Networks: Potentials and Challenges

With the severe spectrum shortage in conventional cellular bands, millimeter wave (mmW) frequencies between 30 and 300 GHz have been attracting growing attention as a possible candidate for next-generation micro- and picocellular wireless networks. The mmW bands offer orders of magnitude greater spectrum than current cellular allocations and enable very high-dimensional antenna arrays for further gains via beamforming and spatial multiplexing. This paper uses recent real-world measurements at 28 and 73 GHz in New York, NY, USA, to derive detailed spatial statistical models of the channels and uses these models to provide a realistic assessment of mmW micro- and picocellular networks in a dense urban deployment. Statistical models are derived for key channel parameters, including the path loss, number of spatial clusters, angular dispersion, and outage. It is found that, even in highly non-line-of-sight environments, strong signals can be detected 100-200 m from potential cell sites, potentially with multiple clusters to support spatial multiplexing. Moreover, a system simulation based on the models predicts that mmW systems can offer an order of magnitude increase in capacity over current state-of-the-art 4G cellular networks with no increase in cell density from current urban deployments.

http://apps.fcc.gov/ecfs/document/view;NEWECFSSESSION=ThTmVg1SGvsFqgxGKYfckQC26BmBGYLH2jpL5z0dMms1j21m5YTC!-1110365353!-349327291?id=60001013324

Millimeter Wave Channel Modeling and Cellular Capacity Evaluation

We report a visible-light wireless point-to-point communication link operating at 513 Mbit/s gross transmission rate (net Mbit/s). The bit-error ratio of the uncoded data was smaller than for an illumination level of lx. The link was based on a commercial thin-film high-power phosphorescent white LED, an avalanche photo diode, and off-line signal processing of discrete multitone signals. Quadrature-amplitude modulation, bit- and power-loading, as well as symmetrical clipping were successfully employed in pushing the gross transmission rate beyond 500 Mbit/s. Adaptation of the clipping level increased the data rate only by 2%, while simulations predicted an enhancement of 20%. Obstacles towards higher data rates as well as potential remedies are discussed. We predicted that data rates of over 1 Gbit/s can be achieved with the same setup and under the same experimental conditions if these obstacles are overcome.

513 Mbit/s Visible Light Communications Link Based on DMT-Modulation of a White LED

Understanding ultra-wide-band (UWB) propagation channels is a prerequisite for UWB system design as well as communication-theoretic and information-theoretic investigations. This paper surveys the fundamental properties of UWB channels, pointing out the differences to conventional channels. If the relative bandwidth is large, the propagation processes, and therefore path loss and shadowing, become frequency-dependent, and the well-known wide-sense stationary uncorrelated scattering model is not applicable anymore. If the absolute bandwidth is large, the shape of the impulse responses as well as the fading statistics change. This paper also describes methods for measuring UWB channels and extracing channel parameters. Throughout this paper, the relationship between channel properties and other areas of UWB research are pointed out.

Ultra-Wide-Band Propagation Channels

Non-line-of-sight (NLOS) identification and mitigation carry significant importance in wireless localization systems. In this paper, we propose a novel NLOS identification technique based on the multipath channel statistics such as the kurtosis, the mean excess delay spread, and the root-mean-square delay spread. In particular, the IEEE 802.15.4a ultrawideband channel models are used as examples and the above statistics are found to be well modeled by log-normal random variables. Subsequently, a joint likelihood ratio test is developed for line-of-sight (LOS) or NLOS identification. Three different weighted least-squares (WLSs) localization techniques that exploit the statistics of multipath components (MPCs) are analyzed. The basic idea behind the proposed WLS approaches is that smaller weights are given to the measurements which are likely to be biased (based on the MPC information), as opposed to variance-based WLS techniques in the literature. Accuracy gains with respect to the conventional least-squares algorithm are demonstrated via Monte-Carlo simulations and verified by theoretical derivations.

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NLOS identification and weighted least-squares localization for UWB systems using multipath channel statistics

Editors. Prime Contributors. Preface. Acknowledgments. Abbreviations & Acronyms. 1 Introduction to UWB Signals and Systems (Andreas F. Molisch). 1.1 History of UWB. 1.2 Motivation. 1.3 UWB Signals and Systems. 1.4 Frequency Regulation. 1.5 Applications, Operating Scenarios and Standardisation. 1.6 System Outlook. References. Part I Fundamentals. Introduction to Part I (Wasim Q. Malik and David J. Edwards). 2 Fundamental Electromagnetic Theory (Mischa Dohler). 2.1 Introduction. 2.2 Maxwell's Equations. 2.3 Resulting Principles. References. 3 Basic Antenna Elements (Mischa Dohler). 3.1 Introduction. 3.2 Hertzian Dipole. 3.3 Antenna Parameters and Terminology. 3.4 Basic Antenna Elements. References. 4 Antenna Arrays (Ernest E. Okon). 4.1 Introduction. 4.2 Point Sources. 4.3 The Principle of Pattern Multiplication. 4.4 Linear Arrays of n Elements. 4.5 Linear Broadside Arrays with Nonuniform Amplitude Distributions. 4.6 Planar Arrays. 4.7 Design Considerations. 4.8 Summary. References. 5 Beamforming (Ben Allen). 5.1 Introduction. 5.2 Antenna Arrays. 5.3 Adaptive Array Systems. 5.4 Beamforming. 5.5 Summary. References. 6 Antenna Diversity Techniques (Junsheng Liu, Wasim Q. Malik, David J. Edwards and Mohammad Ghavami). 6.1 Introduction. 6.2 A Review of Fading. 6.3 Receive Diversity. 6.4 Transmit Diversity. 6.5 MIMO Diversity Systems. References. Part II Antennas for UWB Communications. Introduction to Part II (Ernest E. Okon). 7 Theory of UWB Antenna Elements (Xiaodong Chen). 7.1 Introduction. 7.2 Mechanism of UWB Monopole Antennas. 7.3 Planar UWB Monopole Antennas. 7.4 Planar UWB Slot Antennas. 7.5 Time-Domain Characteristics of Monopoles 7.6 Summary. Acknowledgements. References. 8 Antenna Elements for Impulse Radio (Zhi Ning Chen). 8.1 Introduction. 8.2 UWB Antenna Classification and Design Considerations. 8.3 Omnidirectional and Directional Designs. 8.4 Summary. References. 9 Planar Dipole-like Antennas for Consumer Products (Peter Massey). 9.1 Introduction. 9.2 Computer Modelling and Measurement Techniques. 9.3 Bicone Antennas and the Lossy Transmission Line Model. 9.4 Planar Dipoles. 9.5 Practical Antenna. 9.6 Summary. Acknowledgements. References. 10 UWB Antenna Elements for Consumer Electronic Applications (Dirk Manteuffel). 10.1 Introduction. 10.2 Numerical Modelling and Extraction of the UWB Characterisation. 10.3 Antenna Design and Integration. 10.4 Propagation Modelling. 10.5 System Analysis. 10.6 Conclusions. References. 11 Ultra-wideband Arrays (Ernest E. Okon). 11.1 Introduction. 11.2 Linear Arrays. 11.3 Null and Maximum Directions for Uniform Arrays. 11.4 Phased Arrays. 11.5 Elements for UWB Array Design. 11.6 Modelling Considerations. 11.7 Feed Configurations. 11.8 Design Considerations. 11.9 Summary. References. 12 UWB Beamforming (Mohammad Ghavami and Kaveh Heidary). 12.1 Introduction. 12.2 Basic Concept. 12.3 A Simple Delay-line Transmitter Wideband Array. 12.4 UWB Mono-pulse Arrays. 12.5 Summary. References. Part III Propagation Measurements and Modelling for UWB Communications. Introduction to Part III (Mischa Dohler and Ben Allen). 13 Analysis of UWB Signal Attenuation Through Typical Building Materials (Domenico Porcino). 13.1 Introduction. 13.2 A Brief Overview of Channel Characteristics. 13.3 The Materials Under Test. 13.4 Experimental Campaign. 13.5 Conclusions. References. 14 Large- and Medium-scale Propagation Modelling (Mischa Dohler, Junsheng Liu, R. Michael Buehrer, Swaroop Venkatesh and Ben Allen). 14.1 Introduction. 14.2 Deterministic Models. 14.3 Statistical-Empirical Models. 14.4 Standardised Reference Models. 14.5 Conclusions. References. 15 Small-scale Ultra-wideband Propagation Modelling (Swaroop Venkatesh, R. Michael Buehrer, Junsheng Liu and Mischa Dohler). 15.1 Introduction. 15.2 Small-scale Channel Modelling. 15.3 Spatial Modelling. 15.4 IEEE 802.15.3a Standard Model. 15.5 IEEE 802.15.4a Standard Model. 15.6 Summary. References. 16 Antenna Design and Propagation Measurements and Modelling for UWBWireless BAN (Yang Hao, Akram Alomainy and Yan Zhao). 16.1 Introduction. 16.2 Propagation Channel Measurements and Characteristics. 16.3 WBAN Channel Modelling. 16.4 UWB System-Level Modelling of Potential Body-Centric Networks. 16.5 Summary. References. 17 Ultra-wideband Spatial Channel Characteristics (Wasim Q. Malik, Junsheng Liu, Ben Allen and David J. Edwards). 17.1 Introduction. 17.2 Preliminaries. 17.3 UWB Spatial Channel Representation. 17.4 Characterisation Techniques. 17.5 Increase in the Communication Rate. 17.6 Signal Quality Improvement. 17.7 Performance Parameters. 17.8 Summary. References. Part IV UWB Radar, Imaging and Ranging. Introduction to Part IV (Anthony K. Brown). 18 Localisation in NLOS Scenarios with UWB Antenna Arrays (Thomas Kaiser, Christiane Senger, Amr Eltaher and Bamrung Tau Sieskul). 18.1 Introduction. 18.2 Underlying Mathematical Framework. 18.3 Properties of UWB Beamforming. 18.4 Beamloc Approach. 18.5 Algorithmic Framework. 18.6 Time-delay Estimation. 18.7 Simulation Results. 18.8 Conclusions. References. 19 Antennas for Ground-penetrating Radar (Ian Craddock). 19.1 Introduction. 19.2 GPR Example Applications. 19.3 Analysis and GPR Design. 19.4 Antenna Elements. 19.5 Antenna Measurements, Analysis and Simulation. 19.6 Conclusions. Acknowledgements. References. 20 Wideband Antennas for Biomedical Imaging (Ian Craddock). 20.1 Introduction. 20.2 Detection and Imaging. 20.3 Waveform Choice and Antenna Design Criteria. 20.4 Antenna Elements. 20.5 Measurements, Analysis and Simulation. 20.6 Conclusions. Acknowledgements. References. 21 UWB Antennas for Radar and Related Applications (Anthony K. Brown). 21.1 Introduction. 21.2 Medium- and Long-Range Radar. 21.3 UWB Reflector Antennas. 21.4 UWB Feed Designs. 21.5 Feeds with Low Dispersion. 21.6 Summary. References. Index.

Ultra-Wideband Antennas and Propagation: For Communications, Radar and Imaging

Millimetre Wave Antennas for Gigabit Wireless Communications

Complete and comprehensive application-focused reference on millimetre wave antennas Millimetre Wave Antennas for Gigabit Wireless Communications covers a vast wealth of material with a strong focus on the current design and analysis principles of millimetre wave antennas for wireless devices. It provides practising engineers with the design rules and considerations required in designing antennas for the terminal. The authors include coverage of new configurations with advanced angular and frequency filtering characteristics, new design and analysis techniques, and methods for filter miniaturization. The book reviews up-to-date research results and utilizes numerous design examples to emphasize computer analysis and synthesis whilst also discussing the applications of commercially available software. Key Features: Advanced and up-to-date treatment of one of the fastest growing fields of wireless communications Covers topics such as Gigabit wireless communications and its required antennas, passive and active antenna design and analysis techniques, multibeam antennas and MIMO, IEEE 802.15.3c, WiMedia, and advanced materials and technologies Offers a practical guide to integrated antennas for specific configurations requirements Addresses a number of complex, real-world problems that system and antenna engineers are going to face in millimetre-wave communications industry and provides solutions Contains detailed design examples, drawings and predicted performance This book is an invaluable tool for antenna professionals (engineers, designers, and developers), microwave professionals, wireless communication system professionals, and industries with microwave and millimetre wave research projects. Advanced students and researchers working in the field of millimetre wave engineering will also find this book very useful.

Millimetre Wave Antennas for Gigabit Wireless Communications: A Practical Guide to Design and Analysis in a System Context

Ultra Wide Band (UWB) wireless communications offers a radically different approach to wireless communication compared to conventional narrow band systems. Global interest in the technology is huge. This paper reports on the state of the art of UWB wireless technology and highlights key application areas, technological challenges, higher layer protocol issues, spectrum operating zones and future drivers. The majority of the discussion focuses on the state of the art of UWB technology as it is today and in the near future.

Ultra wideband: applications, technology and future perspectives

A communications device such as a personal identity card is in the form of a badge or label worn on the outside of the wearer's clothing. The badge includes a first layer of a transparent material (11) having an inner surface that is contoured with a retroreflecting repeating pattern. A second layer (12) also of a transparent material has an inner surface with a reciprocating retroreflecting pattern. Sandwiched between the two layers is a layer of liquid crystal material (13) the refractive index of which can be varied through the application of an electric field. When the refractive index of the layer (13) is close to that of the first (11) and second (12) layers, incident radiation passes through the device with little scattering. However, as the refractive index of the layer (13) is varied by application of an electric field, incident radiation is retroreflected from the contoured interface of the first layer (11) with the layer (13). The communications device is capable of retroreflecting incident radiation and modulating the radiation, by altering the refractive index of the layer (13), so that the reflected beam is capable of delivering information to a receiver. In this way information can be delivered in a non-contact environment using a device that requires very little power to operate.

David J. Edwards

Papers

Ultra-Wideband Antennas and Propagation: For Communications, Radar and Imaging

Millimetre Wave Antennas for Gigabit Wireless Communications

Millimetre Wave Antennas for Gigabit Wireless Communications: A Practical Guide to Design and Analysis in a System Context

Ultra wideband: applications, technology and future perspectives

Communications device retroreflecting incident modulated radiation