A5046457020- Microwave Engineering and Waveguides
- Geophysical Methods and Applications
- Antenna Design and Analysis
- Advanced Antenna and Metasurface Technologies
- Millimeter-Wave Propagation and Modeling
- Advanced MIMO Systems Optimization
- Microwave Imaging and Scattering Analysis
- Radio Wave Propagation Studies
- Microwave and Dielectric Measurement Techniques
- Ultra-Wideband Communications Technology
- Electromagnetic Simulation and Numerical Methods
- Underwater Acoustics Research
- Wireless Communication Networks Research
- Cooperative Communication and Network Coding
- Indoor and Outdoor Localization Technologies
- Seismic Waves and Analysis
- Electromagnetic Scattering and Analysis
- Semiconductor Lasers and Optical Devices
- Radar Systems and Signal Processing
- Geophysical and Geoelectrical Methods
- Radio Frequency Integrated Circuit Design
- Antenna Design and Optimization
- Photonic and Optical Devices
- Advanced Wireless Communication Techniques
- Precipitation Measurement and Analysis
University of Bath
2012-2024
Royal Military College of Canada
1996
Phase noise is one of the fundamental performance parameters in modern radar, communication, spectroscopic, and metrological systems. In this paper, a phase theory has been developed for FMCW radar A new design equation derived to specify maximum bound on allowable source level The nonlinear decorrelation function due coherent mixing analyzed propagation delays less than coherence time reference oscillator, spectral broadening target responses discussed delay times greater time. effects...
The successful operation of buried infrastructure within urban environments is fundamental to the conservation modern living standards. Open-cut methods are predominantly used, in preference trenchless technology, effect a repair, replace or install new section network. This is, part, due inability determine position all utilities below carriageway, making open-cut desirable terms dealing with uncertainty since progressively exposed during excavation. However, damage carriageway and disrupt...
This paper reports a simple and inexpensive method for preparing fine scale (<italic>Ø</italic> 260 μm) high-density Magnéli phase (Ti<sub>n</sub>O<sub>2n−1</sub>) conductive ceramic fibres.
Phase noise in radar transmitters is known to raise the floor around large targets, making impossible detection & tracking of small targets nearby. This paper presents phase-noise modelling techniques, with a focus on homodyne FMCW radars, accurately predict level phase expected display. models sub-systems inside typical are presented. We also discuss cancellation coherent systems for short-ranges and analyse situation longer ranges. Practical measurements from millimetre-wave system...
Mapping the Underworld (MTU), a major initiative in UK, is focused on addressing social, environmental and economic consequences raised from inability to locate buried underground utilities (such as pipes cables) by developing multi-sensor mobile device. The aim of MTU device different types assets real time with use automated data processing techniques statutory records. records, even though typically being inaccurate incomplete, provide useful prior information what under ground where....
Phase noise in radar transmitters is known to raise the floor around large targets, making impossible detection & tracking of small targets nearby. This paper presents phase-noise modelling techniques, with a focus on homodyne FMCW radars, accurately predict level phase expected display. models sub-systems inside typical are presented. We also discuss cancellation coherent systems for short-ranges and analyse situation longer ranges. Practical measurements from millimetre-wave system...
We address the problem of accurately locating buried utility segments by fusing data from multiple sensors using a novel Marching-Cross-Section (MCS) algorithm. Five types are used in this work: Ground Penetrating Radar (GPR), Passive Magnetic Fields (PMF), Gradiometer (MG), Low Frequency Electromagnetic (LFEM) and Vibro-Acoustics (VA). As part MCS algorithm, formulation extended Kalman Filter (EKF) is proposed for marching existing tracks scan cross-section (scs) to next one; rules...
A deterministic approach to model radio propagation channels in complex environments and use the study diversity techniques is described. The simulation based on geometric optics uses ray tracing techniques. effects of all rectangular obstacles are considered by model. Both reflection refraction taken into account. Simulation results presented reliability these examined comparing them with those obtained from measurements at 60 GHz. Also it shown that possible minimise time an appropriate...
The nonlinear frequency sweep in frequency-modulated continuous-wave radar systems is analyzed. main lobe broadens with the fast Fourier transform presence of distortion, which makes it difficult to resolve closely spaced targets. A novel modified-adaptive-sampling method presented. To demonstrate validity presented technique, a computer simulation was conducted, and results show marked improvement shape spectrum range resolution.
Simulation results for the capacity distribution of an indoor multiple input output (MIMO) communications system are presented. Results based on ray traced propagation data micro- and macro-MIMO array configurations. Capacity levels compared with well-known mathematical uncorrelated Rayleigh fading. Significant gains seen using a configuration.
Light- and voltage-induced changes in the microwave reflectivity of semiconductors can be used to study kinetics mechanisms electron transfer at semiconductor|electrolyte interfaces. The theory method is developed illustrated by numerical calculations steady-state response for low-doped silicon. results define range rate constants that should experimentally accessible using methods. time frequency responses light-induced are considered, it shown they derive values recombination constants.
When applied to ground penetrating radar (GPR), the multiple signal classification (MUSIC) algorithm is an important frequency estimation method as it can detect very closely spaced targets, particularly when one of target responses substantially less than another. The MUSIC however must be seeded with number targets find and will indicate that regardless actually present. In addition, there no reliable indication magnitude targets. presence relatively low levels noise prone reporting...
This paper considers a new location scheme for ultra wideband (UWB) positioning system. The newly adopted combines the time difference of arrival (TDOA) and angle (AOA) techniques in order to enhance accuracy system compared classical technique (TDOA). is simulated sports tracking application football field. Results are with results from similar using TDOA establish proof-of-concept. Simulation shows that actually giving better performance an acceptably longer processing time. has promise...
TV white space is a general term for the geographical redundancies in broadcast bands. The re-use of current interest due to change digital transmission many parts world. This has led biggest re-structuring bands since their creation. represent prime section spectrum, which currently some space. paper attempts quantify number available south-west UK where switch over now complete. It shown that, high and flat terrain, there little spectrum free. suggests that limiting access this large scale...
Many studies into the use of GPR to detect targets assume that are ideal reflectors. In reality most have been in ground for many years and settled suffered some contamination or corrosion. Iron pipe particular can be hard find with GPR. Some possible corrosion processes suggest a varying conductivity permittivity profile may established around pipe. The consequences such induced profiles radar return greatly diminished classic look-down mode operation. analysis shows novel look through...
In many contemporary electronic systems, phase noise sets the bound on achievable performance. Radar systems are no exception, with actual radar signals carrying significant amounts of due to high transmit frequencies. coherent radars, some sidebands received signal cancelled mixing in receiver. The sampling clock used sample intermediate frequency (IF) also introduces noise/jitter. This paper focuses contribution clock's overall sampled homodyne FMCW systems. We develop a model relating and...
This paper proposes a novel GPR system based on the Orthogonal Frequency Division Multiplexing (OFDM) technique. The selection of major parameters for OFDM are considered. An example configuration is simulated. Target positions can be determined with high accuracy, even when in presence noise. Finally, potential benefits using presented.