A team of ECE faculty members led by Assistant Professor Chung-Tse Michael Wu (PI) have received an Early Concept Grant for Exploratory Research (EAGER) award from the NSF for the project titled "Directional Modulation Non-Contiguous OFDM Retrodirective Communication for Secure IoT." This project includes Associate Professor Waheed Bajwa and Distinguished Professor Narayan Mandayam as co-PIs. The total award amount for this two-year project is $300,000.
This project aims to address a critical security issue in IoT applications that are susceptible to malicious spoofing attacks via an innovative PHY solution combining Non-Contiguous Orthogonal Frequency Division Multiplexing (NC-OFDM) transmission and a directional modulation retrodirective array. As compared with traditional OFDM transmissions, NC-OFDM transmissions take place over a subset of active subcarriers to either avoid incumbent transmissions or for strategic considerations. On the other hand, retrodirective antenna arrays are well known to be able to respond to the interrogator by sending a signal back to the interrogator location without a priori knowledge, which is particularly useful in a multipath-rich environment. One way to realize the directional modulation functionality is to use time-modulated antenna arrays, in which the aliasing effects resulting from the time-modulation frequency are used to distort the signals in the undesired directions. Furthermore, the project will establish that the unique integration of NC-OFDM and directional modulation enabled by a time-modulated retrodirective antenna array whose modulation frequency is the NC-OFDM subcarrier can potentially lead to an unprecedented level of PHY hardware security against spoofing attacks by an adversary, even when the adversary is equipped with sophisticated Machine Learning based attack techniques.
Congratulations to Michael, Waheed and Narayan!