A Novel Ranging Technique Based on Optical Camera Communications and Time Difference of Arrival

Abstract

In this work, a new Time Difference of Arrival (TDoA) scheme for distance measurement based on Optical Camera Communication (OCC) systems is proposed. It relies on the use of optical pulses instead of radio-frequency signals as the time reference triggers, and the introduction of a rolling shutter camera, whose characteristics allows substituting the timer modules used in conventional TDoA techniques by image processing of the illuminated area in the picture. This processing on the camera’s images provides time measurements and implies and specific analysis, which is presented in this work. The system performance and properties, such as resolution and range, mainly depends on the camera characteristics, such as the frames capture rate and the image quality. This new technique is suitable to be implemented in smartphones or other Commercial Off-The-Shelf (COTS) devices equipped with a camera and speakers.

An Indoor Visible Light Positioning System Using Tilted LEDs with High Accuracy

“…Thus, a noise-free system is considered in this work. The conventional trilateration technique based on a range of three minimum observation points offers the advantage of simple geometrical solutions [ 14 ]. Using the RSS algorithm and 4-Tx (i.e., LEDs), the for the LoS path is given as [ 33 , 34 ]: where and where K is the total number of Txs, is the light source irradiance half-power angle, and φ are the tilted irradiance angle from the k th Tx to the Rx and the receiving incident angle, respectively.…”

“…Most research reported on VLP has focused on the investigation of geometrical properties using triangulation/trilateration, fingerprinting, or proximity methods to determine the transmission distance based on establishing a one-to-one relationship between the target location and its received signal strength (RSS). In such works, the analyses were based on the intensity modulation, angle of arrival [ 9 ], time of arrival [ 10 ], time difference of arrival [ 14 ], time of flight (TOF), and direct detection. In VLP systems, linear least square (LLS) or non-linear least square (NLLS) algorithms are often used for the position estimation [ 15 , 16 , 17 ].…”