![Loading Events](https://sp-ao.shortpixel.ai/client/to_webp,q_glossy,ret_img/https://coe.northeastern.edu/wp-content/plugins/the-events-calendar/src/resources/images/tribe-loading.gif)
- This event has passed.
ECE MS Thesis Defense: Ibrahim Farah
March 22, 2021 @ 10:00 am - 11:00 am
MS Thesis Defense: Multipath Beam Steering for OFDM Systems
Ibrahim Farah
Location: Zoom
Abstract: OFDM systems prove effective in combatting the frequency-selective fading, dispersive response of underwater acoustic channels. Coherent symbol detection requires estimation of this channel response at each receiving element, typically done through tap-based models (Least Squares) or path-based models (Path Identification). This talk presents a spatial processing design which uses a multi-channel receiver to isolate individual multi-path returns, both easing the channel estimation requirements and increasing the SNR for symbol detection. The beam steering algorithms are considered in both a coherent and differential OFDM system context and include narrowband and broadband beamforming to the principal, stable path, as well as narrowband and broadband null-steering. These spatial processing algorithms are then extended to an iterative implementation, which approaches the theoretical performance for a beamformer with full multipath channel knowledge. The performance of these algorithms is compared to their single-channel equivalents using both the LS and PI algorithms for coherent detection.