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International Telemetering Conference Proceedings / October 17-20, 1994 / Town & Country Hotel and Conference Center, San Diego, California / The Royal Artillery Range (RA Range) is the British Army's weapons practice range in the Outer Hebrides of Scotland. The large sea range is also used by the Royal Air Force and Royal Navy for new weapons system evaluation and in service practice firing. This paper describes the telemetry facility comprising of two prime sites separated by 40 miles of open sea. Tracking antennas and receivers are at the remote island site of St Kilda with data processing and control at the Range Control Base (RCB), Benbecula. To improve operational capabilities and effectiveness, full remote control and monitoring of the multiple receivers and combiners has been installed. Radar tracking outputs are processed in the telemetry computer to produce individual antenna pointing demands.

International Telemetering Conference Proceedings / October 26-29, 1992 / Town and Country Hotel and Convention Center, San Diego, California / The GPS Satellite System provides precise determination of time, space, and position of aerospace (airborne) vehicles during flight and flight test situations. The cost of "GPS" equipment has been decreasing dramatically -- a phenomenon similar to that which was experienced with "hand held" calculators 20 years or so ago. By the use of a multigain (and beam) antenna and GPS, a very low cost single axis system can be utilized for reception of telemetry and at the same time to provide accurate position, velocity, and acceleration information concerning the airborne vehicle.

The need to monitor geophysical properties of first year ice (FYI) in the Arctic is increasing as this type of sea ice becomes more prevalent. One such method of monitoring the Arctic is the use of electromagnetic remote sensing techniques. These methods determine dielectric properties of the illuminated sea ice by interpreting how the electromagnetic waves interact within the medium. In the literature, there are empirical formulas relating these dielectric properties to the geophysical properties of the sea ice. The contributions of this research are the development and testing of a surface based active microwave remote sensor to monitor sea ice growth in the winter through the reconstruction of the time series complex permittivity profile of FYI. / October 2017

In this dissertation, channel modeling for Terahertz (THz) channels and designs of nano devices for THz communications are studied. THz communication becomes more and more important for future wireless communication systems that require an ultra high data rate, which motivates us to propose new nano device designs based on graphene and new system models for the THz channel. Besides, the multiple-input multiple-output (MIMO) antenna technique is well known to increase the spectral efficiency of a wireless communications system. Considering THz channels' particular characteristics, MIMO systems with reconfigurable antennas and distributed antennas are proposed. We compare the differences between MIMO systems in the GHz and THz bands, and highlight the benefits of using multi antennas in the THz band. The work on nano device designs provides two antenna designs with single walled carbon nanotubes (SWCNTs) and graphene nano ribbon (GNR). First, we analyse the spectral efficiency of an SWCNT bundled dipole antenna based MIMO system in the Terahertz band. Two scenarios are considered: the large scale MIMO and the conventional scale MIMO. It is found that, in order to get the maximum spectral efficiency, the CNT bundle size should be optimized to obtain a tradeoff between the antenna efficiency and the number of antennas for a given area. We also discuss the random fluctuation in the bundle size during the CNT bundled antenna fabrication which reduces the system spectral efficiency. Then, we propose reconfigurable directional antennas for THz communications. The beamwidth and direction can be controlled by the states of each graphene patch in the antenna, and the states can be easily configured by changing the electrostatic bias voltage on each element. The work on reconfigurable MIMO system proposes a new antenna array design for MIMO in the THz band. First, the path loss and reflection models of the THz channel are discussed. Then, we combine the graphene-based antenna and the THz channel model and propose a new MIMO antenna design. The radiation directions of the transmit antennas can be programmed dynamically, leading to different channel state matrices. Finally, the path loss and the channel capacity are numerically calculated and compared with those of the GHz channel. The results show that for short range communications, the proposed MIMO antenna design can enlarge the channel capacity by both increasing the number of antennas and choosing the best channel state matrices. The work on MIMO channels proposes a statistical model for the MIMO channel with rough reflection surfaces in the THz Band. First, our analysis of scattering from a rough surface indicates that the reflection from a single surface can be a cluster of rays. Secondly, a new MIMO model for THz communications is proposed. In this model, the number of multipaths is highly dependent on the roughness of the reflecting surfaces. When the surface is ideally smooth, the MIMO channel is sparse and as a result, the capacity is sub-linear with the MIMO scale. On the other hand, when the surface is rough, more degrees of freedom are provided by the scattered rays. Finally, channel capacities with different surface roughness are numerically calculated and compared between different MIMO scales. The results show that in contrast to the GHz range, large scale THz multiple antennas may not provide as much multiplexing gain. Therefore, it is necessary to determine the antenna scale according to the actual propagation environment. The work on distributed antenna systems (DAS) proposes a new DAS model in the THz band. First, the model of DAS in the THz frequency is discussed, which has fewer multipaths than that in the GHz band. Then, we analyze the characteristics of the DAS model and point out that the channel is very sparse if the number of antennas on the base station (BS) is very large. Besides, we provide reasons for the fact that DAS can have a large number of degrees of freedom. We compare the capacities of MIMO systems with DAS and without DAS. The results show that for THz channels, increasing the number of antenna units (AUs) is much more important than increasing the number of antennas in one AU. Finally, we propose an antenna selection and precoding scheme which has very low complexity. / Graduate

The quest for the direct detection and observation of gravitational waves remains one of the lasting scientific challenges of the 20th century, and one that will continue on into the 21 st. Concepts and technologies are being developed that will, early in the new millennium, allow their direct observation for the first time. This will be the beginning of the gravitational wave astronomy revolution. The LISA (Laser Interferometer Space Antenna) mISSIOn is one of the cornerstones of this revolution. Observing in the low-frequency band, it will provide information about our universe that cannot be gathered from the ground. This band contains sources fundamental to our understanding of how the universe began and operates. In turn, fundamental to the LISA mission is the concept of drag-free control. This provides the relatively undisturbed environment for the test-masses which form the references for the measurement of the gravitational waves. Without it the effect of gravitational waves would be but a whisper amongst a cacophony of disturbances. It is drag-free control for the LISA mission which forms the basis for the majority of this thesis. The research and development work carried out by the author has involved the development of a control model of the LISA dragfree control system to assess its feasibility. The author proposes a different approach to the problems involved from that suggested by other authors. It is shown that this approach, unlike those suggested in the mission baseline studies, fulfills the control requirements for the LISA mission. Technological risk assessment in general, as well as that associated with the LISA mission, is also considered.

With ample radio transmitters scattered throughout urban landscape, RF energy scavenging emerges as a promising approach to extract energy from propagating radio waves in the ambient environment to continuously charge low power electronics. With the ability of generating power from RF energy, the need for batteries could be eliminated. The effective distance of a RF energy scavenging system is highly dependent on its conversion efficiency. This results in significant limitations on the mobility and space requirement of conventional RF energy scavenging systems as they operate only in presence of physically large antennas and conversion circuits to achieve acceptable efficiency. This thesis presents a number of novel design strategies in the antenna and rectifier designs for miniaturized RF energy scavenging system. In the first stage, different energy scavenging systems including solar energy scavenging system, thermoelectric energy scavenging system, wind energy scavenging system, kinetic energy scavenging system, radio frequency energy scavenging system and hybrid energy scavenging system are investigated with regard to their principle and performance. Compared with the other systems, RF energy scavenging system has its advantages on system size and power density with relatively stable energy source. For a typical RF energy scavenging system, antenna and rectifier (AC-DC convertor) are the two essential components to extract RF energy and convert to usable electricity. As the antenna occupies most of the area in the RF energy scavenging system, reduction in antenna size is necessary in order to design a miniaturized system. Several antennas with different characteristics are proposed in the second stage. Firstly, ultra-wideband microstrip antennas printed on a thin substrate with a thickness of 0.2 mm are designed for both half-wave and full-wave wideband RF energy scavenging. Ambient RF power is distributed over a wide range of frequency bands. A wideband RF energy scavenging system can extract power from different frequencies to maximize the input power, hence, generating sufficient output power for charging devices. Wideband operation with 4 GHz bandwidth is obtained by the proposed microstrip antenna. Secondly, multi-band planar inverted-F antennas with low profile are proposed for frequency bands of GSM 900, DCS 1800 and Wi-Fi 2.4 GHz, which are the three most promising frequency bands for RF energy scavenging. Compared with previous designs, the triple band antenna has smaller dimensions with higher antenna gain. Thirdly, a novel miniature inverted-F antenna without empty space covering Wi-Fi 2.4 GHz frequency band is presented dedicated for indoor RF energy scavenging. The antenna has dimensions of only 10 × 5 × 3.5 mm3 with appreciable efficiency across the operating frequency range. In the final stage, a passive CMOS charge pump rectifier in 0.35 μm CMOS technology is proposed for AC to DC conversion. Bootstrapping capacitors are employed to reduce the effective threshold voltage drop of the selected MOS transistors. Transistor sizes are optimized to be 200/0.5 μm. The proposed rectifier achieves improvements in both power conversion efficiency and voltage conversion efficiency compared with conventional designs. The design strategies proposed in this thesis contribute towards the realization of miniaturized RF energy scavenging systems.

The thesis covers the following topics: Assuming a partonic structure of the Pomeron we give predictions for diffractive heavy flavour production at the Tevatron and the LHC and diffractive Higgs production at the LHC in leading-order approximation. For the latter the dominant background processes are also considered. We obtain results on single as well as double diffractive cross sections assuming a Donnachie-Landshoff-type Pomeron flux factor. Measurements of the single inclusive jet cross section at the Tevatron by the CDF Collaboration maybe suggest a modified picture of QCD in the large E(_T) range. A parameter fit of a neutral heavy vector boson Z(^1) to the CDF data, in leading order perturbation theory, is performed, and the question of how the corresponding single inclusive jet cross-sections and the dijet angular distributions at the LHC are affected by this additional Z' is discussed. We test a model, motivated by the former R(_b) and R(_c) "crisis", which contains extra vector fermions. We suggest an alternative indirect test of the possible existence of new heavy quark flavours at the LEP2 collider, which turns out to give the clearest signal. We calculate qq cross sections within this framework, including one loop corrections. Hadronic antenna patterns can provide a valuable diagnostic tool for probing the origin of the reported excess of high x, Q(^2) events at HERA. We present quantitative predictions for the distributions of soft particles and jets in standard deep inelastic scattering eq → eq events and in events corresponding to the production of a narrow colour-triplet scalar resonance. We also study the patterns corresponding to Higgs production and decay in high- energy hadron-hadron collisions. In particular, the signal gg → H → bb and background gg → bb processes are shown to have very different radiation patterns, and this may provide a useful additional method for distinguishing Higgs signal events from the QCD background. The process eq → eq + γ exhibits radiation zeros, i.e. configurations of the final-state particles for which the scattering amplitude vanishes. We study these zeros for both e(^+)u and e(^+)d scattering. The latter exhibits a new type of zero which to our knowledge has not previously been identified. The observability of radiation zeros at HERA is discussed. In the framework of this new type of zero we also study the process e(^+)e(^-) → qqγ. We calculate the positions of these zeros for u-quark and d-quark production and assess the feasibifity of identifying the zeros in experiments at high energies. The radiation zeros are shown to occur also for massive quarks, and we discuss how the bbγ final state may offer a particularly clean environment in which to observe them.