Demo: Improving Visible Light Backscatter Communication with Delayed Superimposition Modulation

Visible light backscatter communication (VLBC) has shown great potential in IoT field. LCD, often used as optical modulator in a VLBC system, mainly limits the data rate to sub-Kbps due to its slow state transition. There is a great demand for speed improvement, to support both low latency and high throughput communication in IoT deployment. With the observation of nonlinear and time-varying characteristics of LCD, we present sys, a novel modulation scheme named Delayed Superimposition Modulation (DSM) to achieve 4kbps, which is 4x rate over the status-quo. This design is robust in the presence of LCD heterogeneity in practical setting.