Preface

Ultra wideband (UWB) has advanced and merged as a technology, and many more people are aware of the potential for this exciting technology. The current UWB field is changing rapidly with new techniques and ideas where several issues are involved in developing the systems. Among UWB system design, the UWB RF transceiver and UWB antenna are the key components. Recently, a considerable amount of researches has been devoted to the development of the UWB RF transceiver and antenna for its enabling high data transmission rates and low power consumption. Our book attempts to present current and emerging trends in research and development of UWB systems as well as future expectations.

Chapter 1 presents RF transceiver architecture for ultra-wideband (UWB) data communications which can fabricate in a small chip area. Actually, the transceiver design offers a huge challenge of this UWB technology as it requires low cost, low power consumption and single chip transceiver architecture. This chapter highlights the current design issues of RF transceiver which will empower readers to make the further developments in UWB transceiver.

Chapter 2 presents an IR-UWB timing synchronization algorithm for achieving rapid, accurate and low-complexity synchronization. The suggested approach improves the estimation performance of the original dirty template algorithms.

Chapter 3 talks about the implementation of the low-power low-cost CMOS biomedical radar using UWB pulse for heart rate monitoring with improved accuracy and reliable performance compared with conventional heart rate measurement devices built using discrete components. This work will contribute in the development of next generation of non-invasive real-time medical monitoring methods.

Chapter 4 approaches a pre-filtering method for UWB channel estimation based on the theory of compressed sensing (CS), whose measurement matrix is just a Toeplitz matrix. The presented approach improves the channel estimation accuracy.

Chapter 5 describes the features of the UWB channel that should be taken into account when it is being considered for medical applications, in particular in hospital scenarios. These scenarios include cases where the human body is in motion and the mathematical models of the channel have been developed based on actual measurements.

#### X Preface

Chapter 6 presents a design of a cooperative wavelet scheme for the multi-relay, multiscale and multi-lag diversity, which can be widely applied in the ultra-wideband communications and underwater acoustic communications.

Preface XI

one with an SLTR and another one with an SSIR. These filters are compact in size and provide a wider upper stopband resulting from resonator bandstop characteristics.

Chapter 14 presents a study on UWB coexistence with the 3G and 4G Cellular Systems. The methodology used to account for the impact of UWB interference on the coverage range and capacity of the interfered systems has been explained in detail. Finally, it has been applied in a set of study cases in scenarios involving the 3G and 4G selected

Chapter 15 discusses the performance of the transmission of UWB signals over two distinctive optical based networks. A low-cost RoF solution based on direct modulation of a VCSEL and two polymer optical fibers are presented and the UWB signal transmission performance is assessed. It is considered two high performance PF-GI POFs with diameters of 62.5 mm and 120 mm and with bandwidth distance products higher than 1 GHz\_Km. Experimental measurements of packet error rate (PER) and minimum transmitted powers to achieve the maximum allowed PER showed that it is possible to have a viable transmission at data rates of 480 Mbps, 200 Mbps and 53.3 Mbps over 100, 150 and 200 meters of PF-GI-POF, respectively,

It is believed that this book serves as a comprehensive reference for graduate students who are wishing to greatly enhance their knowledge of all aspects of UWB systems.

> **Mohammad Abdul Matin** Institut Teknologi Brunei Brunei Darussalam

systems.

preceded by a 1 meter wireless link.

Chapter 7 introduces the-state-of-art of the conventional and modern UWB antennas. First, it talks about some of the conventional UWB antennas and then discusses and summarizes some novel types of omni-directional UWB antennas and wideband techniques, mainly concentrate on two types: the planar monopole UWB antenna and the printed monopole UWB antenna. Several novel types of directional UWB antenna and wideband techniques are also summarized including the UWB printed wide-slot antenna and the UWB dielectric resonator antennas (DRA). Finally, to avoid the interference between the UWB system and other exist communication systems, various notch function techniques for UWB antenna design are introduced.

Chapter 8 presents the concept and the design methodology of a generic SWB antenna architecture (SWBA). The antenna architecture provides powerful isolated-parameters to control the antenna characteristics, such as resonance-shifting, resonance matching, bandwidth broadening, diffraction reduction, and SWB pattern maintaining.

Chapter 9 describes the design of active integrated antenna for UWB (ultra-wideband) application.

Chapter 10 presents several UWB-MIMO antennas and a critical description of relevant characteristics need to take into account for the design and a review of presented designs in the literature classified according to the techniques applied to improve the mutual coupling and enhance isolation. Some new designs of UWB-MIMO antennas, based on simple radiating elements, are also introduced, analyzed and compared in this chapter.

Chapter 11 presents several UWB antennas with single, dual, triple and quadruple band-notched characteristics using different resonator structures including the CPW resonators,λ/4-resonators and the MLs. The bandwidths and center frequencies of all these notches can be controlled independently by adjusting the dimensions of the resonators which are also discussed in this chapter.

Chapter 12 discusses the cable effects on measuring compact planner monopole antennas for UWB applications. The small ground plane of the antennas causes the currents to flow back on the surface of the feeding cable, results in secondary radiation. This leads to discrepancies between the simulated and measured performances and uncertainties in the design of the antenna.

Chapter 13 presents advanced UWB-bandpass filters based on slotted linear taperedline resonator (SLTR) and slotted step-impedance resonator (SSIR) structures for size reduction and improved stopband performances. A comprehensive treatment of slotted resonators and both ends of the resonator with interdigital coupled lines is described. The design concept is demonstrated using two filter examples including one with an SLTR and another one with an SSIR. These filters are compact in size and provide a wider upper stopband resulting from resonator bandstop characteristics.

X Preface

application.

and compared in this chapter.

resonators which are also discussed in this chapter.

performances and uncertainties in the design of the antenna.

Chapter 6 presents a design of a cooperative wavelet scheme for the multi-relay, multiscale and multi-lag diversity, which can be widely applied in the ultra-wideband

Chapter 7 introduces the-state-of-art of the conventional and modern UWB antennas. First, it talks about some of the conventional UWB antennas and then discusses and summarizes some novel types of omni-directional UWB antennas and wideband techniques, mainly concentrate on two types: the planar monopole UWB antenna and the printed monopole UWB antenna. Several novel types of directional UWB antenna and wideband techniques are also summarized including the UWB printed wide-slot antenna and the UWB dielectric resonator antennas (DRA). Finally, to avoid the interference between the UWB system and other exist communication systems, various

Chapter 8 presents the concept and the design methodology of a generic SWB antenna architecture (SWBA). The antenna architecture provides powerful isolated-parameters to control the antenna characteristics, such as resonance-shifting, resonance matching,

Chapter 9 describes the design of active integrated antenna for UWB (ultra-wideband)

Chapter 10 presents several UWB-MIMO antennas and a critical description of relevant characteristics need to take into account for the design and a review of presented designs in the literature classified according to the techniques applied to improve the mutual coupling and enhance isolation. Some new designs of UWB-MIMO antennas, based on simple radiating elements, are also introduced, analyzed

Chapter 11 presents several UWB antennas with single, dual, triple and quadruple band-notched characteristics using different resonator structures including the CPW resonators,λ/4-resonators and the MLs. The bandwidths and center frequencies of all these notches can be controlled independently by adjusting the dimensions of the

Chapter 12 discusses the cable effects on measuring compact planner monopole antennas for UWB applications. The small ground plane of the antennas causes the currents to flow back on the surface of the feeding cable, results in secondary radiation. This leads to discrepancies between the simulated and measured

Chapter 13 presents advanced UWB-bandpass filters based on slotted linear taperedline resonator (SLTR) and slotted step-impedance resonator (SSIR) structures for size reduction and improved stopband performances. A comprehensive treatment of slotted resonators and both ends of the resonator with interdigital coupled lines is described. The design concept is demonstrated using two filter examples including

bandwidth broadening, diffraction reduction, and SWB pattern maintaining.

communications and underwater acoustic communications.

notch function techniques for UWB antenna design are introduced.

Chapter 14 presents a study on UWB coexistence with the 3G and 4G Cellular Systems. The methodology used to account for the impact of UWB interference on the coverage range and capacity of the interfered systems has been explained in detail. Finally, it has been applied in a set of study cases in scenarios involving the 3G and 4G selected systems.

Chapter 15 discusses the performance of the transmission of UWB signals over two distinctive optical based networks. A low-cost RoF solution based on direct modulation of a VCSEL and two polymer optical fibers are presented and the UWB signal transmission performance is assessed. It is considered two high performance PF-GI POFs with diameters of 62.5 mm and 120 mm and with bandwidth distance products higher than 1 GHz\_Km. Experimental measurements of packet error rate (PER) and minimum transmitted powers to achieve the maximum allowed PER showed that it is possible to have a viable transmission at data rates of 480 Mbps, 200 Mbps and 53.3 Mbps over 100, 150 and 200 meters of PF-GI-POF, respectively, preceded by a 1 meter wireless link.

It is believed that this book serves as a comprehensive reference for graduate students who are wishing to greatly enhance their knowledge of all aspects of UWB systems.

> **Mohammad Abdul Matin** Institut Teknologi Brunei Brunei Darussalam

**Chapter 1** 

© 2012 Matin, licensee InTech. This is an open access chapter distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use,

distribution, and reproduction in any medium, provided the original work is properly cited.

© 2012 Matin, licensee InTech. This is a paper distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

As UWB pulse itself does not contain information, we must add digital information to the analog pulse through modulation. The MB-OFDM systems are dealing with

Ultra-wideband (UWB) technology has developed rapidly over the past several years due to its high date rate with small current consumption in short range communication. According to Shannon-Hartley theorem, the maximum rate of clean (or arbitrarily low bit error rate)

Where, C is the channel capacity, BW is the bandwidth, SNR is the ratio of average received signal power to the noise spectral density. It can be seen from (1), channel capacity increases linearly with bandwidth but only logarithmically with SNR which means capacity increases as a function of BW faster than as a function of SNR and with a wide bandwidth, high data rate can be achieved with a low transmitted power. Its main applications include imaging systems, vehicular radar systems and communications and measurement systems. Ever since, the FCC released unlicensed spectrum of 3.1-10.6 GHz for UWB application in 2002, UWB has received significant interest from both industry and academia. Mutli-Band OFDM (MB-OFDM) and Direct-Sequence UWB (DS-UWB) are two existing competing proposals for UWB; each gained multiple supports from industry. The MB-OFMD divides the 3 ~ 10 GHz UWB spectrum into fourteen sub-bands which has a 528 MHz bandwidth. Due to incompatible of these two proposals, it experiences huge difficulties in commercialization of UWB technology. On the other hand, Impulse Radio UWB (IR-UWB) has become a hot research area in academia due to its low complexity and

<sup>2</sup> *C BW SNR* log 1 (1)

date through an AWGN (Additive white Gaussian Noise) channel, is limited to

**Ultra-Wideband RF Transceiver** 

Additional information is available at the end of the chapter

M. A. Matin

http://dx.doi.org/10.5772/49095

**1. Introduction** 

low power.

**2. UWB modulation** 
