Recent developments in computing technology have generated a demand for more streamlined and effective test systems. By replacing traditional in-chassis wired interconnects with a broadcast wireless system, fault detection and error susceptibility will drastically improve, input/output capabilities will expand, and routing complexity will decrease. Ultra-wideband impulse radio's (UWB-IR) characteristic multipath-immunity...
This thesis deals with target localization using multiple-input multiple-output (MIMO) radars. In the field of communications, navigation, radar, and sensing networks, one of the common and most sophisticated problems is target localization. We develop a target localization scheme in distributed MIMO radar systems using bistatic range measurements. The localization approach...
Movement pattern detection can be applied in a variety of applications such as assisting independent living of seniors at home, behaviour understanding in surveillance systems, sports analytics, and robotics. This project develops a scheme that fuses information from different sensors to detect movement patterns. This report contains three main parts:...
Pulsed ultra-wideband (UWB) radio uses extremely short pulses to transmit information. Such pulses provide very fine timing information, which has led to technological advances in high-precision localization. This thesis investigates UWB localization strategies with a focus on receiver synchronization algorithms for time-difference-of-arrival localization to achieve centimeter accuracies in a 3-dimensional...
Accurate positioning has become an active research area in recent years. It has a wide range of applications in many fields such as navigation, asset tracking, health care, proximity marketing/location-based advertising, and sport analytics. Transmitter positioning via radio frequency (RF) signals is the most widely encountered scenario, and it uses...
Traditional localization techniques rely on triangulation or trilateration, where in a set of three or more stationary known locations is used to estimate a “client” position. For inertial navigation, these techniques can estimate client positions merely using the measured data from tri-axial accelerometers and gyroscopes. However, the use of double...
In this paper, a Direction of Arrival (DOA) based system is proposed. This method searches the direction relative to the array to find where the signal source is located. The proposed system can achieve sub-meter level accuracy with a near real-time update rate. Also, we introduced several refinement methods including...
Threshold-based time of arrival (TOA) estimation is a technique for high-precision indoor localization. Existing threshold selection methods, such as xed thresh- old and normalized threshold methods, do not consider the signal-to-noise radio (SNR) value at the receiver. This is not desired for high-precision positioning. A proper threshold value depends on...
Pulsed ultra-wideband (UWB) radio uses extremely short pulses to transmit
information. Such pulses provide very fine timing information, which has led to
technological advances in high-precision localization. This thesis focuses on
techniques and experiments of Time-Difference-of-Arrival (TDOA) localization of
a large number of simultaneous sources. First, common localization techniques
such...
Wearable sensors with an inertial measurement unit (IMU) are popular for indoor positioning and activity pattern detection. The IMUs can be connected to a wireless transmission module, allowing users to monitor and process motion-related parameters remotely. Because of the complexity and uncertainty of signals in indoor environments, a radio frequency...
The desire to apply short-range wireless communication systems to telemetry sensor networks in a metal-enclosed chamber has prompted this study. This thesis will discuss the design of an infrared (IR) communication system for a wireless low-power, low-data- rate sensor network in a metal enclosure. This design requires an in-depth understanding...
Time of Arrival (TOA) is a popular technique used for geolocation. This thesis evaluates the use of TOA techniques indoors. The accuracy of measuring distances using TOA is dependent on the bandwidth of the system and the multipath conditions between the receiver and transmitter. System bandwidth has a significant effect...
fIndoor wireless local area networks (LAN's) and personal area networks (PAN’s) have evolved very rapidly in the recent past. The indoor wireless LAN's are mainly dominated by narrow-band technologies like the IEEE 802.11a,b which are short range and provide data rates of 1 Mbps to 54 Mbps. The Bluetooth has...
In modern digital communication systems, error correction codes (ECC) are widely used and play an important role. The main effect of ECCs is to reduce the transmission error caused by channel noise, thereby protecting data and increasing the quality of information transmission. In addition, high spectral efficiency is desired in...
Inter-symbol interference is one of the major factors that make the realization of high-data-rate digital communications system complex. Current designs face two main challenges: how to efficiently utilize the available bandwidth and how to reduce the hardware complexity of the transmitter and receiver. Traditional solutions use a single-band architecture. When...
Optical wireless communication (OWC) is an alternative to radio frequency (RF)communication with a signi cantly larger and unregulated spectrum. In OWC systems, optical orthogonal frequency division multiplexing (O-OFDM) with intensity modulation and direct detection (IM/DD) is commonly used. There are two common signal structures in most OWC systems based on...
Powerline communication (PLC), is becoming a more commonplace method for data transmission, however it is still a very new medium for data transmission, and international standards for powerline communication are still in the process of being developed and established. PLC can provide a means of simplifying the device connectivity to...
One of the key challenges in downlink multiuser multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) systems is the mitigation of the multi-access interference when different users share the same subcarriers. In this work, the block diagonalization (BD) algorithm for inter-user interference pre-cancelation is extended to MIMO-OFDM systems. However, in...
Ultra-wideband (UWB) radio is the transmission of data using an extremely wide bandwidth and very low power spectral density. In this thesis, the mereits and challenges of UWB architectures versus conventional narrowband architectures will be compared. Pulsed UWB systems can be implemented with very simple architectures. These advantages make UWB...
The US military is evaluating the capabilities of emerging technologies based on IEEE 802.16 standard as a potential commercial off-the-shelf solution to support the communication requirements of the future war.
In the last few years, development in military and telecommunication industries have focused on an intensive use of broadband systems,...
This paper proposes a novel means of using analog correlators to improve upon existing Ultra-Wideband receiver architectures. Current architectures aim for an all-digital design for the sake of ease of implementation and conceptual simplicity. This causes some notable design challenges including an ultra-high sampling rate, and difficulty capturing multipath energy....
The uncontrolled growth in domains such as surveillance systems, health care services, and finance produce a large amount of data and contain potentially sensitive data that can become public if they are not appropriately sanitized.
Motivated by this issue, we introduce a privacy filter (PF), a novel non-negative matrix factorization...
There has been tremendous technological advancement in the area of high-speed indoor wireless local area networks (WLAN's) in recent years. All the existing tech- nologies such as IEEE 802.11a,b are bandwidth limited and high powered systems. The challenge any wireless technology faces is to minimize both the power consumption and...
Direct sequence spread spectrum (DSSS) was initially used for anti-jamming in military applications and was later developed in other commercial applications. Walsh codes, which are a set of mutually orthogonal codes, are one type of the spreading codes used in DSSS systems. For any spreading codes of length N, these...
The dependence of the substrate resistance, R[subscript sub], for MOS transistor RF modeling on transistor biasing and layout is studied from device simulations and measurements. Though R[subscript sub] is found to be bias dependent, the error incurred by assuming a constant value equal to the DC resistance is not significant....
Analog-to-Digital Data Converters (ADCs) used in instrumentation and measurements often require high absolute accuracy, including excellent linearity and negligible dc offset. Incremental data converters (IDCs) provide a solution for such measurement applications. Since IDCs are essentially delta-sigma converters with reset operation before each conversion, they retain most of the advantages...
The ability to accurately locate people and objects indoors will enable opportunities for control and automation of indoor environments. Current indoor localization solutions require dedicated hardware which must be custom tailored to each application. There are large technological, societal, and economic benefits in developing a more general purpose system that...
There is a large and growing market for portable consumer audio products
with very small size. As the size of these products is reduced, the area occupied
by batteries becomes significant and hence limits the number of batteries to one.
In order to build such small products, high levels of...
Radiation is part of our life. Most people may know a radioactive source is very dangerous. But there are very few situations people are exposed to uncontrolled radionuclides above background. A radioactive source can emit gamma rays which are the highest energy type in electromagnetic radiation.[2] Gamma rays are like...
In wireless communication, channel state information (CSI) is essential for data detection. Fast fading coefficients estimation is important in order to acquire accurate CSI. Kalman filters (KF) are widely used for real time parameter estimation and can be used to estimate the fast fading coefficients of a mobile communication channel....
Massive MIMO is a promising technique for future 5G communications due to its high spectrum and energy efficiency. To realize its potential performance gain, accurate channel state information at transmitter side (CSIT) is essential. Frequency division duplex (FDD) is widely employed by the most cellular systems today. However, it requires...
Recent publications show that successive approximation register (SAR) analog to digital converters (ADC) are capable of achieving high efficiency over other ADC topologies. Furthermore, techniques have been adopted to process signals with low activity periods, such as biomedical and industrial sensors. Prior work used least- significant bit first quantization (LSBFQ)...
A fully integrated CMOS GPS receiver RF front end optimized for low power operation is presented. The system operates with a supply voltage down to 250 mV. A prototype has been fabricated in a 0.13μm CMOS process and includes a low voltage LNA, quadrature oscillators, and quadrature mixers. It exhibits...
Delay insensitive asynchronous circuitry provides significant advantages with
respect to substrate noise due to localized switching. The differences between the
substrate noise from NULL Convention Logic (NCL) and traditional Clocked
Boolean Logic (CBL) are described and analyzed based on measured results. A test chip fabricated in the TSMC 0.25 um...
This thesis presents a channelized digital receiver design for UWB sytems in a multipath indoor environment. The UWB technology has been used for commercial and military purposes due to a number of advantages such as low-power consumption, noise-like and carrier free. The energy of UWB signal is spread over a...
In this thesis, a novel Direct-Charge-Transfer (DCT) integrator structure is proposed, which can settle much faster than regular switch-capacitor integrators. A new Spread-Spectrum Dynamic Element Matching (SS-DEM) algorithm is also introduced, which can effectively spread or shape the nonlinearity error of multi-bit DAC in the feedback path, thus improve the...
Medical imaging technologies play a vital role in early diagnosis of disease by providing internal images of the human body to medical professionals. Computed Tomography (CT) is currently the most commonly used medical imaging technology because it is easy to use, detectors and scanners are constantly improving, and more importantly,...
All-digital PLLs promise flexible and precise frequency modulation continous-wave(FMCW) radar signal signal for 77GHz radar applications. Such PLLs require digitally-controlled oscillators(DCO) with wide frequency tuning range and high resolution to address a range of applications and low phase noise requirements. In this thesis, novel resonator structures with ne capacitance/inductance switching...
An enhanced swing differential Colpitts VCO (ESDC-VCO) dramatically improves
the swing of a Colpitts VCO by allowing the signal to swing below ground and above the
supply voltage. Fabricated in a 1P8M 0.13 um CMOS process, the ESDC-VCO operates
at 4.9GHz with a 0.475-V supply and consumes 2.7mW. The measured...
Ultra-wideband (UWB) radio has become an attractive alternative for wireless communications due to the robustness to multipath fading, low power transmission, mostly-digital implementation, and low cost. Furthermore, short-range, high data-rates applications are possible with UWB radios due to the wide spectral
allocations at 3.1 - 10.6 GHz.
This thesis presents...
The stupendous growth in wireless and mobile devices in the recent years has prompted researchers to look at innovative approaches that enable effective use of the available resources. In this thesis, we propose a medium access control (MAC) protocol, referred to as EM-MAC, that enables wireless devices with multi-channel access...
Physical-Layer Network Coding (PNC) is a promising technique that has great potentials for improving the achievable data rates of end-to-end flows through higher packet transmission rates, thereby increasing the overall network throughput. In this thesis, we study the performance of the PNC transmission techniques for unidirectional end-to-end flows in multi-hop...
We develop efficient coordination techniques that support inelastic traffic in large-scale distributed dynamic spectrum access DSA networks. By means of any learning algorithm, the proposed techniques enable DSA users to locate and exploit spectrum opportunities effectively, thereby increasing their achieved throughput (or "rewards" to be more general). Basically, learning algorithms...
The enormous success of wireless technology has recently led to an explosive demand for, and hence a shortage of, bandwidth resources. This expected shortage problem is reported to be primarily due to the inefficient, static nature of current spectrum allocation methods. As an initial step towards solving this shortage problem,...
The proliferation of body worn autometric devices has been enabled by advances in low-power electronics and fueled by the quantified-self movement. These devices range in complexity from pedometers to clinical vital sign measurement. They all share the same drawback, typically the most expensive and heaviest component, the battery. The future...
Estimating the carrier frequency from a modulated waveform is one of the most important functions of a coherent signal receiver. Good performance and low bit error rates are obtained by coherent demodulation. Therefore, exact knowledge of the received signal carrier frequency is critical for communication systems. Also due to the...
With an increasing number of wireless applications at microwave frequencies, the frequency spectrum is becoming quite crowded. Due to this congestion, the current state of technology is leading towards upper microwave and millimeter wave spectra as they also offer other distinct advantages such as larger bandwidth and smaller component footprint....
A Mobile Ad-hoc NETwork (MANET) is collection of wireless mobile nodes without a network infrastructure or centralized administration. Although MANETs can be used in many applications, such as mobile Internet, military communication, and disaster relief networks, a number of challenges remain. These include routing, medium access control, security, scalability, energy...
This work focusses on the modeling and the development of efficient coupled simulation techniques for MEMS based RF oscillators. High-level models for MEMS based varactors have been discussed and their accuracy issues are identified, based on comparisons with numerical simulations. A faster simulation approach based on the time-domain shooting method...
The amount of instruction level parallelism (ILP) that can be exploited depends
greatly on the size of the instruction window and the number of in-flight instructions
the processor can support. However, this requires a register file with a large set of
physical registers for renaming and multiple ports to provide...