19th June, 2020

Dr. Aamir Hasan is Associate Professor and Associate Dean, UG Education & Accreditation at Dhanani School of Science and Engineering of Habib University. He acquired his Ph.D. in wireless communications from University of Texas at Austin. He further Mastered in War studies and Strategic studies from the PAF Air War College. Before joining Habib as Associate Professor and ECE Program Director in 2018, Dr. Hasan had also served as a lecturer at UT Austin and taught at Air University. His contribution to the design and implementation of PAF Next Generation Networks was recognised by the bestowal of Tamgha-i-Imtiaz (military).

Dr. Hasan’s talk was focused on wireless networks, known as ad hoc networks and his research on the topic. Ad hoc networks unlike cellular networks, as the speaker explained, are independent of infrastructure or any base station. Entirely wireless, these networks are formed out of nodes which transmit radio waves on their own and organise themselves without any physical control centre. Other than not requiring infrastructure and being able to be implemented in locations or situations where constructing infrastructure is not plausible, the benefits of a wireless network system also include its ease and speed of deployment. With these features it can prove useful in military set up and disaster response needs.

However, the complexity of wireless communication does pose challenges to achieving an efficient networking system. Dr. Hasan outlined the major problems to show how there is an inherent communication versus coordination problem in wireless networking. Since nodes transmit data concurrently there is chance of cross interference of data and since there is no form of centralised control, it is hard to manage the network. This also means that practically not all nodes could communicate at the same time.

Before expanding on his research on how to resolve the complex challenge of ad hoc network, Dr. Hasan gave a summarized explanation of how radio wave networks function. A lesson on wave spectrum, bandwidth, Shannon’s capacity formula and rate versus range, he touched upon his own work. Dr. Hasan’s work looked into answering the question of how nodes (transmitter and receiver) within ad hoc networks could be arranged most efficiently, avoiding cross interference and ensuring highest potential quality. His research led to the conclusion that the problem related to available area and how many transmitters could efficiently be packed into it. Using a specialised metric for measuring successful ad hoc transmissions, Dr. Hasan and his team were able to come up with a formula for the optimal size of the ‘guard zone’ or the area a transmitter and receiver node could cover. The application of this theory will allow active receivers to disable other transmitters in the way to receive data coming from its transmitter.

Dr. Hasan’s research was published in 2004, in which the hybridization of different network communicating methods, direct signals and frequency hopping for ad hoc networking was emphasised. The speaker further elaborated how hybrid processes of those applied in the Bluetooth system also showed promise in application to ad hoc systems. The advantages and potential ad hoc networks carried can revolutionise the future of networking and machine to machine communication.