With the technological advancement, entertainment has become revolutionized and the High-definition (HD) video has become a common feature of our modern amusement devices. Moreover, the demand for wireless transmission of HD video is rising increasingly for its ubiquitous nature, easy installation and relocation. The high bandwidth requirement is the main concern for wireless transmission of high quality video streams. Research has been going on by the consumer electronics industry to provide different solutions of this issue, for the last few years.<p> In this research work, HD video transmission feasibility using the Ultra-wideband (UWB) communication channel is analyzed. The UWB channel is selected for its short-range, high-speed data transmission capability at low-cost, and low-power consumption. The maximum transmitting range of this technology is about 10 m at 100 Mbps data rate. Simulation is conducted by controlling key parameters, such as, in-loop deblocking filter, group of pictures, and quantization parameter of an H.264/AVC encoder. Here, standard HD video streams with different motion characteristics are used, and the impact of these parameters change on the reconstructed video quality and the broadcasting data rate are analyzed. Finally, a generalized parameters settings, and a video content dependent settings for an H.264/AVC encoder are proposed for different bandwidth requirements, as well as acceptable video quality. Performance evaluation of these parameters settings is performed, and the results are quite satisfactory as long as the symbol energy to noise power density ratio, Es/No, is above 15. With the proposed parameters settings, maximum 20 Mbps data rate is achieved with 33.5 dB Y-PSNR.

The demand for efficient and cost-effective transmission and distribution of RF signal is increasing with the rapid development of wireless communication. This thesis studies the effect of using cost-effective vertical cavity surface emitting laser (VCSEL) to distribute ultra wide band (UWB) RF signal. Properties of multimode and single mode VCSEL are studied and simulated using commercial optical design suite. One of the biggest drawbacks of Orthogonal Frequency Division Multiplexing (OFDM) used by UWB is high peak to average power ratio (PAPR). Signal pre-distortion method is proposed to mitigate nonlinear effect from VCSEL optical system. Software connector is implemented to interconnect the Optical and Wireless design suite. Integrated VCSEL optical link and UWB simulation is carried out for the performance of the radio-on-fiber (RoF) system. The RoF system with optimized single mode VCSEL and proposed pre-distortion method is found to be capable of distributing UWB RF signal.

The demand for efficient and cost-effective transmission and distribution of RF signal is increasing with the rapid development of wireless communication. This thesis studies the effect of using cost-effective vertical cavity surface emitting laser (VCSEL) to distribute ultra wide band (UWB) RF signal. Properties of multimode and single mode VCSEL are studied and simulated using commercial optical design suite. One of the biggest drawbacks of Orthogonal Frequency Division Multiplexing (OFDM) used by UWB is high peak to average power ratio (PAPR). Signal pre-distortion method is proposed to mitigate nonlinear effect from VCSEL optical system. Software connector is implemented to interconnect the Optical and Wireless design suite. Integrated VCSEL optical link and UWB simulation is carried out for the performance of the radio-on-fiber (RoF) system. The RoF system with optimized single mode VCSEL and proposed pre-distortion method is found to be capable of distributing UWB RF signal.

With the technological advancement, entertainment has become revolutionized and the High-definition (HD) video has become a common feature of our modern amusement devices. Moreover, the demand for wireless transmission of HD video is rising increasingly for its ubiquitous nature, easy installation and relocation. The high bandwidth requirement is the main concern for wireless transmission of high quality video streams. Research has been going on by the consumer electronics industry to provide different solutions of this issue, for the last few years.<p> In this research work, HD video transmission feasibility using the Ultra-wideband (UWB) communication channel is analyzed. The UWB channel is selected for its short-range, high-speed data transmission capability at low-cost, and low-power consumption. The maximum transmitting range of this technology is about 10 m at 100 Mbps data rate. Simulation is conducted by controlling key parameters, such as, in-loop deblocking filter, group of pictures, and quantization parameter of an H.264/AVC encoder. Here, standard HD video streams with different motion characteristics are used, and the impact of these parameters change on the reconstructed video quality and the broadcasting data rate are analyzed. Finally, a generalized parameters settings, and a video content dependent settings for an H.264/AVC encoder are proposed for different bandwidth requirements, as well as acceptable video quality. Performance evaluation of these parameters settings is performed, and the results are quite satisfactory as long as the symbol energy to noise power density ratio, Es/No, is above 15. With the proposed parameters settings, maximum 20 Mbps data rate is achieved with 33.5 dB Y-PSNR.

In this thesis, we will address several important issues on the direct sequence ultra-wideband (DS-UWB) wireless system and will provide a comprehensive analytical study on DS-UWB with different channel models, as well as the impact of pulse shapes on the overall performance.

IEEE 802.15 High Rate Alternative PHY task group (TG3a) is working to define a protocol for Wireless Personal Area Networks (WPANs) which makes it possible to attain data rates of greater than 110Mbps. Ultra Wideband (UWB) technology utilizing frequency band of 3.168 GHz – 10.6 GHz is an emerging solution to this with data rates of 110, 200 and 480 Mbps. Initially, UWB mode I devices using only 3.168 GHz – 4.752 GHz have been proposed. Low Noise Amplifier (LNA) and I-Q mixers are key components constituting the RF front-end. Performance of these blocks is very critical to the overall performance of the receiver. In general, main considerations for the LNA are low noise, 50 broadband input matching, high gain with maximum flatness and good linearity. For the mixers, it is essential to attain low flicker noise performance coupled with good conversion gain. Proposed LNA architecture is a derivative of inductive source degenerated topology. Broadband matching at the LNA output is achieved using LC band-pass filter. To obtain high gain with maximum flatness, an LC band-pass filter is used at its output. Proposed LNA achieved a gain of 15dB, noise figure of less than 2.6dB and IIP3 of more than -7dBm. Mixer is a modified version of double balanced Gilbert cell topology where both I and Q channel mixers are merged together. Frequency response of each sub-band is matched by using an additional inductor, which further improves the noise figure and conversion gain. Current bleeding scheme is used to further reduce the low frequency noise. Mixer achieves average conversion gain of 14.5dB, IIP3 more than 6dBm and Double Side Band (DSB) noise figure less than 9dB. Maximum variation in conversion gain is desired to be less than 1dB. Both LNA and mixers are designed to be fabricated in TSMC 0.18µm CMOS technology.

In this thesis, we consider a distributed detection problem in wireless sensor networks (WSNs) using ultrawide bandwidth (UWB) communications. Due to the severe restrictions on power consumption, energy efficiency becomes a critical design issue in WSNs. UWB technology has low-power transceivers, low-complexity and low-cost circuitry which are well suited to the physical layer requirements for WSNs. In a typical parallel fusion network, local decisions are made by local sensors and transmitted through a wireless channel to a fusion center, where the final decision is made. In this thesis, we control the number of UWB pulses to achieve the energy efficient distributed detection. We first theoretically characterize the performance of distributed detection using UWB communications. Both AWGN and fading channels are considered. Based on the analysis, we then obtain the minimum number of the pulses per detection to meet the required performance. To achieve a near-optimal design, we further propose a multiple access technique based on the random number of UWB pulses. Finally, the performance evaluation is provided to demonstrate the advantage of our design.

Focusing techniques and detection of targets is usually associated to defense and military use. However in recent past things have moved ahead. Now target detection using UWB radars is being done in many industries and corporations. Radarbolaget AB is one of them; one of their projects uses UWB radars to detect steel strips inside a furnace. This research solves a potential problem of detecting middle steel strip out of total three strip edges which can be seen by radar placed on the front. For better understanding of the reader, existing system and introductory UWB radar principles are discussed. As there can be many solutions to focusing of targets here (steel strip edge detection). Available focusing techniques have been discussed in detail along with the possible physical and simulation setups. Later in the document, detection methods have been proposed. UWB time reversed signal detection is a fairly new method and a very limited research has been done so far. PRBS sequence has been focused on in detection mechanism. Results section show that the pulse of the PRBS works better and produces more promising results rather than a repetitive signal. Time reversal methods for locating the target have been used to find the approximate location of the target. Manual distance calculations from target to the transmitter and receiver have been done. Comparison of actual distance from target to the transmitter is compared with simulation results. Different model simulation setups and their results have proved that using UWB Time reversed signals; a still or moving target can be detected with centimeter window precision.

Wavelength reuse techniques for bidirectional ultra-wide band (UWB) over fiber (UWBoF) networks are presented. The downstream optical signal from the central station (CS) is reused for upstream data transmission with the original data erased at the base station (BS). Two wavelength reuse schemes for the generation of a clear optical carrier at the BS are theoretically analyzed and experimentally demonstrated. In the first scheme, the wavelength reuse is based on phase-modulation to intensity-modulation (PM-IM) conversion and destructive interferencing using a polarization modulator (PolM) and a fiber Bragg grating (FBG). A theoretical analysis is performed which is verified by an experiment. In the second scheme, the wavelength reuse is based on injection locking of a Fabry–Pérot laser diode (FP-LD) and polarization multiplexing. The UWB injection signal contributes to better BERs of both downstream and upstream services and a lower power penalty cause by the wavelength reuse of the whole system than the baseband signal. A bidirectional point-to-point transmission of over a 25-km single-mode fiber (SMF) using a single wavelength from the CS in each scheme is demonstrated.

Ultra Wideband (UWB) communication systems occupy large bandwidths with very low power spectral densities. This feature makes UWB channels highly rich in multipaths. To exploit the temporal diversity, a UWB receiver usually incorporates Rake reception. Each multipath in the channel carries just a fraction of the signal energy. This phenomenon dictates a Rake receiver with a large number of fingers to achieve good energy capture and output signal to noise ratio (SNR). Eventually, the Rake structure becomes very complex from analysis and design perspectives and incurs higher manufacturing cost. The first contribution of this thesis is to propose channel shortening or time domain equalization as a technique to reduce the complexity of the UWB Rake receiver. It is analyzed that most of the existing channel shortening equalizer (CSE) designs are either system specific or optimize a parameter not critical or even available in UWB systems. The CSE designs which are more generic and use commonly critical cost functions may perform poorly due to particular UWB channel profiles and related statistical properties. Consequently, the main contribution of the thesis is to propose several CSE designs to address the specific needs of UWB systems. These CSE designs not only exploit some general but also some UWB specific features to perform the task more efficiently. The comparative analysis of the proposed CSEs, some existing designs and the conventional Rake structures leads towards the conclusion. It is finally shown that the use of CSE at the receiver front end greatly simplifies the Rake structure and the associated signal processing.