Communication Networks: The Next Frontier

In an IoT world, Dr. Benjamin Zaidel of the Faculty of Engineering is using information theory to plan the future of our communication networks

Our world is growing smarter by the minute. We are living in smart homes, monitor our home climate, and remote-control our household appliances. It’s a futuristic reality.
Dr. Benjamin Zaidel of the Alexander Kofkin Faculty of Engineering at Bat-Ilan is already a few steps ahead of the curb, envisioning a world in which vehicles or electronic appliances will communicate with each other independently. “Technology companies are already implementing IoT (Internet of Things) technologies, and in the very near future we’ll be able to have our vehicles communicate with each other, or our fridge remind us we’re out of milk,” he says. “In that kind of reality, most household appliances will have to be network-accessible. However, the number of channels (more generally, “resources”) allocated for our networks today isn’t enough to allocate a separate network channel per each communicating device, so inevitably the communicating devices are going to interfere with each other. My research focuses on ways of maintaining efficient communications through networks offering fewer channels than users.”

Zaidel, 49, a married father of two, joined Bar-Ilan University in 2014. He holds two degrees in Electrical Engineering from Tel Aviv University and a PhD in Electrical Engineering from the Technion. He completed post-doctoral rotation in NTNU in Norway, where he studied vector precoding for the MIMO Gaussian broadcast channel. At the Faculty of Engineering, Zaidel is a senior lecturer specializing in information theory. “Information theory uses mathematical modeling of communication channels to analyze the theoretical limitations of various communication networks. For instance, using the theory I can calculate the maximal Mbps reach of my home network, based on the cables connected and the service provider’s network deployment,” explains Zaidel. “In other words, it’s a theoretical tool aiming to characterize performance limitations, which are crucial when designing a practical system, as they provide guidelines for proper planning of an efficient communication system with close to optimal performance.”

In the past two years, Zaidel has been studying advanced communication techniques designed for future generations of cellular communication. “I’m focusing on theoretical analysis of a specific communication scheme on these systems, with the objective of improving performance. Using this approach, I’m trying to forecast what we can expect as far as maximal performance,” explains Zaidel. “Right now we are focusing on implications of the number of users surpassing the number of available orthogonal channels, and ways of reliably reconstructing the transmitted messages. This new field of research examines communication schemes that may render this theory applicable. Many in the communication industry (as well as academia) are now trying to cope with this issue.”

Collaborating with Dr. Ori Shental of Bell Labs and Distinguished Prof. Shlomo Shamai of the Technion, Zaidel presented the theory in last year’s annual IEEE International Symposium on Information Theory (ISIT). “Last year we began running the analysis using heuristic tools, which are not fully mathematically proven. Nevertheless, they still produced the correct result,” says Zaidel. “Last fall we had a breakthrough, and we succeeded in finding a mathematical tool that closes things rigorously and still produce the same result, but in a more mathematically comprehensive way. This enabled us to produce closed form analytical expressions. This result can be used as a reference for comparing other schemes. It’s a theoretically impressive result, and moreover, it provides an analytical foundation for our theory, and reinforces the usage of our suggested approach not just by numerical methods, but also by means of full mathematical analysis.”

This past June, Zaidel returned to the ISIT 2018 conference held in Vail, Colorado, where he presented his theory and published a short conference paper (jointly with his collaborators). The method developed is no small feat, but as far as Zaidel is concerned – his work is far from finished. “There is a whole series of issues that still need to be studied, in order for us to have all the information about these schemes’ capabilities,” he explains. “The result we produced is related to a specific communication channel setting, an ideal one. The next step is to make the network more complex, and add more features of practical channels, in order to simulate a real network. There is still a lot of work to be done if things are to be fully comprehended. And I intend to do just that.”