Cone Geometry-Based Simultaneous 3D Position and Orientation Estimation for Visible Light Systems

With the widespread application of light emitting diodes (LEDs) and the rapid evolution of visible light communication (VLC), visible light-based positioning (VLP) is envisioned as a promising solution for indoor positioning due to its high accuracy and environmental friendliness. However, the performance of VLP is significantly affected by the unknown orientation of the user equipment (UE) and system parameters uncertainty. Besides, high computation complexity and vulnerability to hardware degradation of the VLP algorithms are also the challenges to meet. To handle the above issues, a novel cone geometry-based simultaneous position and orientation estimation (SPO) scheme with low complexity is proposed. By modeling the field of view (FOV) of the photodiode (PD) as a cone, the geometry relationship between the sensed LEDs and the UE position and orientation is established. The binary values of whether the LEDs signals are received or not are exploited, and an alternating flashing strategy for the LED arrays is designed to guarantee normal illumination and reduce bandwidth consumption. Moreover, the theoretical lower bound derived from Kanatani-Cramer-Rao bound (KCRB) is provided to analyze optimality of the estimator. Simulation results demonstrate the proposed scheme achieve an excellent performance gain with low complexity over two classical SPO baseline, and the critical factors that affect the performance are investigated.