SDR-Based Chip-less RFID Reader

Research at WINGS Lab, University at Buffalo. Chip-less RFID promises very low-cost tagging, but reading accuracy is fragile — tag resonances shift and a fixed-frequency reader misses them.

I built an SDR-based reader and authored an Out-of-Tree block in GNU Radio that adjusts centre frequency dynamically rather than assuming a fixed band. Tag geometry was optimised in CST Studio and validated against measured S-parameters on a VNA, so simulation and bench agreed before anything was fabricated.

40% improvement in tag-reading accuracy, and a substantial reduction in prototyping cost by resolving design questions in simulation instead of in copper.