Key research themes
1. How do RF impairments affect performance in multipath cascaded fading channels, especially in vehicular communications?
This research area focuses on quantifying and modeling the impact of radio frequency (RF) impairments, particularly in-phase/quadrature-phase imbalance (IQI), on wireless communication systems operating over cascaded multipath fading channels, such as the N*Nakagami-m model relevant to vehicular-to-vehicular (V2V) communications. Understanding these impairments is critical as they cause significant performance degradations in realistic low-cost direct-conversion transceivers commonly used in modern wireless technologies.
2. Can dependency structures in multipath fading channels enable strictly positive zero-outage capacity under slow fading?
This line of inquiry investigates how statistical dependencies between fading channels—modeled via copula theory—can yield a strictly positive zero-outage capacity (ZOC) in slow fading multipath environments, contrary to classical assumptions that ZOC is zero. Such positive ZOC implies outage-free transmission without retransmissions, addressing the stringent latency and reliability demands of ultra-reliable low-latency communications (URLLC) in 6G and beyond.
3. What are the accurate performance characterizations of multipath fading channels under generalized fading models and diversity techniques such as selection combining and OFDM?
This theme examines advanced statistical and analytical frameworks to characterize the bit error rate (BER), outage probability, and fading distributions of multipath fading channels modeled by generalized distributions (e.g., alpha-mu, Nakagami-m, kappa-mu) and unified models (Fox's H-function). It also covers performance impacts of diversity combining (selection combining, MISO, MIMO), orthogonal frequency division multiplexing (OFDM), and trellis coded modulation (TCM) in multipath fading environments.