In order to achieve Full Duplex (FD) communication, currently studied solutionsfor the commercial sector rely on advanced Self-Interferece Cancellation (SIC)techniques to remove the transmitted signal from the received one. This thesis expandsthe research of these techniques by evaluating their potential usage in militarycommunication scenarios where requirements and conditions are distinct,firstly, by identifying, categorizing and describing a set of previously proposedsic techniques and secondly, by performing a comprehensive simulation andanalysis of two suggested sic techniques as part of a FD transceiver. Though themajority of the considered SIC techniques was determined to be potentially implementablein military FD transceivers, some frequency-dependent techniquesand techniques prohibiting omnidirectional communication could not be used.The simulation and analysis of the two suggested SIC techniques show that undercertain conditions, such as limited transmission power and/or reflective environment,close to complete suppression could be realized even with high nonlineardistortion in the transmit chain.

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<p>A wireless revolution has occurred resulting in the formation of a proverbial backbone of wireless devices that our everyday functionality, productivity, and general way of life have become dependent. Consequently, victimizing an already constrained and finite wireless spectrum with further demands for increased bandwidths, greater channel capacities, and an insatiable plea for faster access rates. In-band full-duplexing (IBFD) is an innovative and encouraging technology that aims to answer this tacit mitigation call by bolstering spectral efficiency through simultaneous same frequency band transmission and reception. Conventionally, transceiver-based systems have their respective transmission and reception dictated by occurring in either disparate time slots (half-duplex) or distinct frequencies (out-of-band full-duplex). By achieving simultaneous same band communication, a theoretical doubling in spectral efficiency is rendered feasible. However, transmitter to receiver leakage, or self-interference (SI), remains the most barring frustration to IBFD realization. Being locally generated, SI is considerably stronger (often 50-100dB) than the desired signal-of-interest (SOI). Left unresolved, this unwanted energy saturates the receiver’s amplifiers and desensitizes its analog-to-digital converters. Thus, rendering the SOI unintelligible. Therefore, a means of self-interference cancellation (SIC) is necessitated to suppress any polluting SI to levels that of or below the receiver’s noise floor.</p><p></p>In this thesis an in-depth history of in-band full duplex technology is first presented, followed by a condensed examination of the SIC domains. Pertinent theory is presented pertaining to noise analysis and estimation relevant to a proposed IBFD transceiver architecture. Finally, a modelled simulation of this transceiver, developed in MATLAB, is presented. Subsequent results detailing an investigative study done on a fully adaptive tapped-branch analog self-interference canceller are shown. Said canceller’s variable phase and amplitude weights are set via real-time training using gradient descent algorithms. Evaluation of the results reveal marginal effect on the SIC efficacy due to transmission path nonlinearity and noise distortions alone. However, expansion of model consideration for conceivable cancellation hardware nonlinearities reveals an indirectly proportional degradation of SIC performance by up to 35dB as distortion levels vary from -80 dBm to -10 dBm. These results indicate consideration of such non-idealities should be an integral part of cancellation hardware design for the preclusion of any intrinsic cancellation impediments.

In this thesis, I conduct the hardware prototyping of a two-way relay system using the National Instruments FlexRIO hardware platform. First of all, I develop several practical mechanisms to solve the critical synchronization issues of the systems, including Orthogonal Frequency-Division Multiplexing (OFDM) frame synchronization at the receiver, source to source node synchronization, and handshaking between the sources and relay nodes. Those synchronization methods control the behavior of the two source nodes and the relay node, which play critical roles in the two-way relay systems. Secondly, I develop a pilot-based channel estimation scheme and validate it by showing the successful self-interference cancellation for the two-way relay systems. In particular, I experiment the self-interference cancellation technique by using several channel estimation schemes to estimate both source to relay channels and relay to source channels. Moreover, I implement the physical layer of a 5 MHz OFDM scheme for the two-way relay system. Both the transmitter and receiver are designed to mimic the Long Term Evolution (LTE) downlink scenario. The physical layer of the transmitter has been implemented in Field-Programmable Gate Arrays (FPGAs) and executed on the hardware board, which provides high throughput and fundamental building blocks for the two-way relay system. The physical layer of receiver is implemented in the real-time controller, which provides the ?exibility to rapidly recon?gure the system. Finally, I demonstrate that the 5MHz OFDM based two-way relay system can achieve reliable communications, when the channel estimation and system synchronization can be correctly executed.

abstract: The demand for the higher data rate in the wireless telecommunication is increasing rapidly. Providing higher data rate in cellular telecommunication systems is limited because of the limited physical resources such as telecommunication frequency channels. Besides, interference with the other users and self-interference signal in the receiver are the other challenges in increasing the bandwidth of the wireless telecommunication system. Full duplex wireless communication transmits and receives at the same time and the same frequency which was assumed impossible in the conventional wireless communication systems. Full duplex wireless communication, compared to the conventional wireless communication, doubles the channel efficiency and bandwidth. In addition, full duplex wireless communication system simplifies the reusing of the radio resources in small cells to eliminate the backhaul problem and simplifies the management of the spectrum. Finally, the full duplex telecommunication system reduces the costs of future wireless communication systems. The main challenge in the full duplex wireless is the self-interference signal at the receiver which is very large compared to the receiver noise floor and it degrades the receiver performance significantly. In this dissertation, different techniques for the antenna interface and self-interference cancellation are proposed for the wireless full duplex transceiver. These techniques are designed and implemented on CMOS technology. The measurement results show that the full duplex wireless is possible for the short range and cellular wireless communication systems. / Dissertation/Thesis / Doctoral Dissertation Engineering 2017

abstract: Both two-way relays (TWR) and full-duplex (FD) radios are spectrally efficient, and their integration shows great potential to further improve the spectral efficiency, which offers a solution to the fifth generation wireless systems. High quality channel state information (CSI) are the key components for the implementation and the performance of the FD TWR system, making channel estimation in FD TWRs crucial. The impact of channel estimation on spectral efficiency in half-duplex multiple-input-multiple-output (MIMO) TWR systems is investigated. The trade-off between training and data energy is proposed. In the case that two sources are symmetric in power and number of antennas, a closed-form for the optimal ratio of data energy to total energy is derived. It can be shown that the achievable rate is a monotonically increasing function of the data length. The asymmetric case is discussed as well. Efficient and accurate training schemes for FD TWRs are essential for profiting from the inherent spectrally efficient structures of both FD and TWRs. A novel one-block training scheme with a maximum likelihood (ML) estimator is proposed to estimate the channels between the nodes and the residual self-interference (RSI) channel simultaneously. Baseline training schemes are also considered to compare with the one-block scheme. The Cramer-Rao bounds (CRBs) of the training schemes are derived and analyzed by using the asymptotic properties of Toeplitz matrices. The benefit of estimating the RSI channel is shown analytically in terms of Fisher information. To obtain fundamental and analytic results of how the RSI affects the spectral efficiency, one-way FD relay systems are studied. Optimal training design and ML channel estimation are proposed to estimate the RSI channel. The CRBs are derived and analyzed in closed-form so that the optimal training sequence can be found via minimizing the CRB. Extensions of the training scheme to frequency-selective channels and multiple relays are also presented. Simultaneously sensing and transmission in an FD cognitive radio system with MIMO is considered. The trade-off between the transmission rate and the detection accuracy is characterized by the sum-rate of the primary and the secondary users. Different beamforming and combining schemes are proposed and compared. / Dissertation/Thesis / Doctoral Dissertation Electrical Engineering 2018

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Measuring atomic displacement inside crystals has been an important field of interest for decades especially in semiconductor industry for its effect on the crystal structure and symmetry, subsequently on the bandgap structure. There are three different image based, diffraction based, and electron holography based techniques using transmission electron microscope (TEM). These methods enable measuring atomic displacement inside specimen. However, among all TEM techniques offering nano-scale resolution measurements, convergent beam electron diffraction (CBED) patterns show the highest sensitivity to the atomic displacement. Higher order Laue zone (HOLZ) lines split by small variations of lattice constant allowing the atomic displacement measurement through the crystal. However it is a cumbersome measurement and it can only reveal the atomic displacement in two dimensions. Therefore, the atomic displacement information at each depth through the specimen thickness is still missing. This information can be obtained by recovering the phase information across the split HOLZ line. The phase profile across the split HOLZ line can be retrieved by the electron interferometry method. The phase of the diffracted beam is the required information to reconstruct the atomic displacement profile through the specimen thickness. In this work, we first propose a novel technique of self-interference of split HOLZ line based on the diffracted beam interferometry which recovers the phase information across the split HOLZ line. The experimental details of the technique have been examined to report the parameters in order to implement the method. Regarding the novelty of the technique and the lack of the of a reference phase profile to discuss the results, phase profile simulation was a main contribution. For simulating the phase profile across the split HOLZ line the Howie-Whelan formula supporting the kinematical theory of diffraction is used. Accordingly, the analytical approach to simulate the phase profiles across the split HOLZ line for three various suggested atomic displacements are studied. Also, the effect of some parameters such as the atomic displacement amplitude, the specimen thickness, and the g reflection is investigated on the phase profile. This study leads to an equation used for fitting the experimental results with the simulated phase profile. Consequently, self-interference of split HOLZ line (SIS-HOLZ) is studied as a method of reconstructing the phase profile across the split HOLZ line which carries the information of atomic displacement through the specimen thickness. / Graduate / 0548 / 0794 / mananrp@uvic.ca

With the wireless technology evolving quickly, so does the demand of speed and efficiency. This makes the companies look for new and better ways to improve the current systems. One way of improving the present systems would be to employ Full Duplex Technology. In recent years the standard has been Half duplex technology with either Time Division Duplexing (TDD) or Frequency Division Duplexing (FDD). The drawback of TDD is that the signals is put in different time slots, meaning if many signals is to be transmitted at the same time there will be a delay. For FDD the signals are sent at different frequencies. This takes up a lot of space in the spectral domain. Full Duplex Technology has the potential to double the spectral efficiency with it'spower to transmit and receive signals simultaneously at the same frequency. The main challenge with Full Duplex (FD) is the leaking Self-Interference (SI) from the transmitter to the receiver. Different methods can be used to suppress the SI in both the digital and the analog domain. Typically the Self-Interference Cancellation (SIC) is split into three parts. The passive Radio Frequency (RF) SIC, which suppresses the signal using for example. antenna separation, antenna polarization or a circulator. The active analog RF cancellation which could for example use a multi-tap analog least mean square adaptive and finally the Digital passband SIC, that is addressed in this thesis. The cancellation in the RF domain needs to suppress enough for the Low Noise Amplifier (LNA) and the Analog to Digital Converter (ADC) to not saturate. The Digital SIC should optimally suppress the signal to the noise floor to be able to demodulate the received signal. In this thesis modelling and reconstruction of the SI signal has been done. An attempt to model the non-linearities from the Power Amplifier (PA), the imbalance from the IQ-mixer and the effects of the circulator has been done to as correctly as possible comply to the real signal distortions. Simulations using experimental data provided by Syntronic SRD was used to evaluate the cancellation for Recursive Least Square (RLS), Ordinary Least Square (OLS) and Normalized Least Mean Square (NLMS) algorithms. The simulations shows that a cancellation of over 45dB within the bandwidth can be achieved using digital cancellation in the baseband. The result shows the importance of having a weakly nonlinear transmit signal to achieve a better performance using FD. It was showed that the linear model shows significantly worse results incomparison to the Generalized Memory Polynomial (GMP) and Memory Polynomial (MP). The MP and GMP model achieve similar results in the weakly non-linear cases but the GMP outperforms the MP model in strongly non-linear cases.

5G är något som växer fram i samhällen över hela världen. Många stormakter så som USA och Ryssland satsar mycket pengar på att skapa användningsområden för 5G, inte minst i militära sammanhang. Sverige använder idag inte 5G i militära sammanhang. Totalförsvarets forskningsinstitut FOI har dock publicerat rapporter om tänkbara användningsområden för 5G i den militära verksamheten. Detta arbete tar det ett steg längre och ser till hur 5G kan nyttjas specifikt i stridslednings- och luftbevakningsbataljonen. Arbetet har en teknisk utgångspunkt och använder teorin militär nytta. Genom att presentera och analysera sju olika funktioner i 5G. Dessa är mjukvarudefinierande nät, multiantennsystem, self-interference cancellation, hantering av flera samtidiga användare, bredbandiga mottagare och millimetervåg, multikonnektivitet vid flera bärvågor och felrättande kodning. Slutsatsen är att 5G mycket väl kan nyttjas i stridslednings- och luftbevakningsbataljonen. Många av funktionerna passar väl in i bataljonens uppgifter och system. Dock skulle det krävas en omfattande ombyggnation av den befintliga arkitekturen av system som används idag för att 5G ska vara möjligt att implementera. Anledningen till detta är att stridslednings- och luftbevakningsbataljonens system är system av system och där ett system ej går att byta ut eller lägga till utan att andra system påverkas.