This paper describes an optical ranging and communication method based on all-phase fast fourier transform (FFT). This kind of system is mainly designed for vehicle safety application. Particularly, the phase shift of the reflecting orthogonal frequency division multiplexing (OFDM) symbol is measured to determine the signal time of flight. Then the distance is calculated according to the time of flight. Several key factors affecting the phase measurement accuracy are studied. The all-phase FFT, which can reduce the effects of frequency offset, phase noise and the inter-carrier interference (ICI), is applied to measure the OFDM symbol phase shift.

Date Published: 3 October 2014
PDF: 6 pages
Proc. SPIE 9224, Laser Communication and Propagation through the Atmosphere and Oceans III, 922419 (3 October 2014); doi: 10.1117/12.2064018

Published in SPIE Proceedings Vol. 9224:
Laser Communication and Propagation through the Atmosphere and Oceans III
Alexander M. J. van Eijk; Christopher C. Davis; Stephen M. Hammel, Editor(s)