PhD position in Wireless Communications/Information Theory

We have an open PhD position in the following NSF sponsored project. We are looking for students with good background in math to work on information theory. Students with an M.Sc. degree or completing one are preferred.

Delay and Energy in Wireless Communications (Joint with Texas A&M University)

Energy consumption has become of increasing importance by the transition in communications to mobile devices with limited battery capacity. At the same time, delay needs to be carefully controlled due to the need to support the proliferation of time-sensitive services, such as video. Seen from a user perspective, these are the main things that affect the mobile experience: energy consumption (how long does the battery last), delay (how long to wait for content). Yet, the desire for low delay and low energy consumption in congested systems conflict. In order to design future communication systems, it is therefore necessary to understand the fundamental tradeoff between energy and delay in congested systems. The insights from this fundamental analysis will be used to jointly design new communications software and energy efficient communication hardware, which will be tested in a wireless testbed. This hardware can be used as basis of future wireless communication devices.  

The project aims to understand the factors that influence energy and delay such as the time characteristics of data to be transmitted and the characteristics of the channel. To obtain a fundamental understanding of these factors, it is necessary to analyze the information theory underlying delay and energy, taking into account realistic features of the systems, including networking and hardware. The project builds on the recent line of work in information theory on finite block length communications. Basically, if the block length is infinite, as in traditional information theory, the delay is also infinite. Therefore, in order to reach a more fundamental understanding of delay, finite block length analysis is needed. However, block length is not a direct indicator of delay. Therefore, finite block length theory has to be developed specifically for investigating delay and energy. Preliminary results show that delay affects energy consumption much more strongly than one would expect from bandwidth constraints alone. The project attacks the tradeoff between delay and energy in four steps. First it develops the basic information theory relating delay and energy. It then applies this to multiuser systems, where spectral efficiency is essential. In the next step, it extends the models with realistic hardware constraints. In the final step, the theory is tested on a hardware testbed with state-of-the-art coding.

Contact: Anders Host-Madsen, [email protected]