Innovative Projects Realized

Performance and Implementation Limits of Full-Duplex Relaying

Wireless relaying has been recently proposed as a promising method in wireless communications that offers considerable performance improvement without the need of high transmission powers. Its operation is based upon the concept of deploying relay terminals in order to forward the information sent by a source terminal to a destination terminal. In this way, the system is able to overcome potential obstacles between source and destination and can take advantage of the available multiple paths and thus exploit the beneficial effects of spatial diversity.

As opposed to half-duplex relaying, in full-duplex relaying the relay terminal receives the signal incident from the source terminal and forwards it to the destination in the same transmission interval, without any sort of buffering [1]-[2]. The advantage of this concurrent retransmission is an increased efficiency in terms of transmitted data rate, with some performance cost. That is, allowing the transmission and reception to occur at the same time offers a data rate equivalent to the conventional wireless communication schemes where no relaying takes place, yet the message received at the relay is corrupted by the signal being forwarded at the same time, causing self-interference which leads to performance degradation. To this end, the main scope of this project is to thoroughly investigate the potential of fullduplex relaying, by jointly taking into account the practically attainable data rate, as well as the performance limitations due to the aforementioned self-interference. Along with the theoretical analysis, the anticipated research will include the potential practical constraints of implementing full-duplex relaying in applications where either fixed (i.e., infrastructure-based) relays or mobile relays are deployed. In this respect, considering the possibility of separating the transmitting and receiving antennas at the relay terminal, the potential of full-duplex relaying will be examined and analyzed as a function of the isolation between the receiving and transmitting ends. In the same context, the effectiveness of interference-cancellation methods employed at the relay terminal will be investigated, both in terms of achievable performance
and complexity, taking into account feasibility issues that may be encountered in practical setups. The results will then be compared with that of half-duplex relaying, both in terms of diversity performance and achievable data rate, aiming at a broad and thorough comparison between full-duplex relaying and its half-duplex counterpart.

The Globalink student will join the wireless communications lab in the Department of Electrical and Computer Engineering at the University of British Columbia and conduct research in the area of full-duplex relaying. The theoretical part of the project will include the mathematical modeling of the problem, writing computer programs for simulating full-duplex relaying, as well as performance analysis.

Experimental Study of Fiber Interaction with a Cylinder Array

The Globalink student will assist a graduate student in developing the apparatus shown in Figure 1. He/she will then conduct experiments on fibres of varying lengths, diameters, mechanical properties and will develop a correlation to predict fibre trapping as a function of the relevant non-dimensional variables.

Photosynthetic protein based solar cells

The student will help with the design, implementation and testing of the solar cells.  Duties include analysis of the ultimate efficiency of various designs, testing of solar electrodes, assistance with the design of solid state solar cells, device modeling and/or measurement of device performance.

Wireless body area sensor network for biomedical applications

The intern will tackle a key area of the project, and be responsible for both hardware and software implementation of this area, including designing and developing components and software libraries, integrating these parts into the rest of the system, and performing testing.

Structure and Function of novel Direct Antimicrobial and Immunomodulatory Peptides

Extension of Image and Video Fingerprinting Algorithm from Grayscale to Color domain

Examining Human Standing Balance Response with Independent Ankle Control

Standing balance is controlled by several inputs, including vision, vestibular sense, and ankle proprioception
Research studies in this field actively engage and manipulate these input mechanisms to examine their
effects on the balance output, mainly muscle actuation in the lower limbs. While significant progress has
been made, it is often difficult to isolate a single input and test its results on the output. The unique Robot
for Interactive Sensor Engagement and Rehabilitation (RISER) has been developed in the UBC CARIS
laboratory for controlling each sense independently to further our understanding of human balance control
and to present new possibilities for the control of bipedal robots [4]. We intend to use this system and the
strategies developed to help safely rehabilitate people who have lost the ability to balance.

For the MITACS Project, we propose that the student expand upon our research by: a) integrating our own
two axis ‘ankle-tilt’ system with the platform to control ankle angle in the sagittal plane, effectively
decoupling ankle proprioception from vestibular input; b) controlling the motion between the tilt-platform
and the Stewart platform in our existing LabVIEW program; c) performing a preliminary experiment to
move the ‘ankle-tilt’ system while holding the motion base steady, so that a blindfolded subject will
experience an ankle movement but no corresponding vestibular or visual stimulation; and d) refining our
mathematical human balance model as a result of the experiments.

Real-time EEG denoising – LabView/FPGA implementation

The candidate will have the chance to combine theoretical aspects of biomedical signal processing with practical hardware implementation in the reconfigurable module and to assist the experimental data gathering process in the Sensorimotor Physiology Laboratory.

Understanding Scenes using Vision and Range Sensing

The Curious George project aims to construct a spatial-semantic modeling system featuring automated learning of object appearance and object-place relations from online annotated database, and the application of these relations to a variety of real-world tasks. The physical system currently developed at UBC, a visually guided mobile robot, can recognize objects in an environment based on imagery collected from the World Wide web, as demonstrated in an international contest known as the Semantic Robot Vision Challenge. The UBC team has won that contest both at AAAI 2007 in Vancouver and at CVPR 2008 in Anchorage, and won the software division in 2009.

Recently, we have begun work on labeling novel scenes with place information using object-place relationship automatically extracted from the web. A summer student working in our lab would help us to integrate our existing technologies to give our robotic system the ability to perform state-of-the-art object recognition and create semantic place maps of realistic environments.  Ultimately the recognition and place mapping system on our robots will form the basis for home robots and assistive robots for home care. There are a wide range of opportunities in the project, ranging from mining the Web for images and semantic information about scenes to working with mobile robots on exploring areas looking for objects.

The student will work closely with senior graduate students to develop and maintain subsystems to enable the robot to understand range images.  New developments in range sensing such as the Microsoft range interface (due in November) will revolutionize sensing.

Improving textual summarization of source code using Latent Dirichlet Allocation (LDA)

Transport Layer Protocol Design for Cognitive Radio Systems

Recent studies have shown that many licensed spectrum bands are under-utilized, which form
spectrum holes [1]. The concept of cognitive radio was introduced in order to increase the
usage of the spectrum [2]. In cognitive radio systems [3], unlicensed users (which are also
called secondary users) can perform sensing over a wide range of spectrum bands. The
secondary users can opportunistically access the unused licensed bands from the legacy
spectrum holders (which are also called primary users). In order words, the secondary users
can utilize the available licensed bands during the period of time when the primary users for
those bands are idle.

The goal of this project is to design and evaluate the performance of transport layer protocols
for cognitive radio systems. In particular, we will design rate adaptation and congestion control
algorithms which can adapt well to the rapid changes in the available bandwidth.

The student's tasks include: Background Reading and Literature Survey, Rate Adaptation and Congestion Control Protocol Design, Performance Evaluation and Comparison and Report Preparation. The student will also give a presentation to other graduate students in the communications and networking research group at the University of British Columbia.

Universal characterization of quantum optical devices: Theory and practice

The primary vision of my group’s research is implementing light as the principal physical medium for quantum information processing. Light is an ideal communication agent: because the energy of the photon is normally much higher than the average temperature of the environment, it can propagate many miles without losing the information it carries. Therefore, no matter what physical system will be the basis for future quantum computers, these computers will have to use photons to talk to each other. Furthermore, even if scientists fail to develop quantum computers in near future, quantum-optical information technology is still useful as a tool for confidential communication protocols whose security is guaranteed by fundamental laws of nature.

While the initial applications showed the promise of our approach, additional work is needed in order to make this procedure a universal standard for quantum device characterization. In particular, a robust algorithmic framework for the process  reconstruction needs to be elaborated. We would like to generalize the maximum-likelihood algorithm for quantum state tomography [3] to estimate the process tensor and its uncertainties directly from the experimental data acquired in homodyne detection, removing the intermediate step of reconstructing  for the “probe” coherent states. This algorithm will improve the stability of the reconstruction and guarantee a physically consistent result.

We also need to improve our understanding of many practical issues involving our process tomography, such as better understanding the sources of error in our procedure and developing a reliable technique for estimating this error and determine the set of coherent states for which the measurements need to be performed in order to achieve a required level of precision in process reconstruction.

If the student prefers theory, he or she can, for example, elaborate the direct algorithm of process reconstruction from the experimental data. On the experimental side, the student can join an experiment on process tomography of the creation and annihilation operators.