Resolution Limit of Single-Photon LiDAR
This work addresses a key limitation in LiDAR technology for applications like autonomous vehicles and remote sensing, though it is incremental in nature.
The paper tackles the fundamental trade-off between spatial resolution and signal-to-noise ratio in single-photon LiDAR systems, deriving theoretical limits for time delay estimation error that align with simulations and real data.
Single-photon Light Detection and Ranging (LiDAR) systems are often equipped with an array of detectors for improved spatial resolution and sensing speed. However, given a fixed amount of flux produced by the laser transmitter across the scene, the per-pixel Signal-to-Noise Ratio (SNR) will decrease when more pixels are packed in a unit space. This presents a fundamental trade-off between the spatial resolution of the sensor array and the SNR received at each pixel. Theoretical characterization of this fundamental limit is explored. By deriving the photon arrival statistics and introducing a series of new approximation techniques, the Mean Squared Error (MSE) of the maximum-likelihood estimator of the time delay is derived. The theoretical predictions align well with simulations and real data.