Direction finding apparatus using tunable fiber optic delay line
US5530778A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 23, 1995 |
| Grant date | Jun 25, 1996 |
| Priority date | — |
| Expiry date | Feb 23, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01Q3/2676
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A direction finding apparatus and method for an RF signal are described which provide a variable time delay in fiber optic cables. A tunable transmitter launches optical emissions of several wavelengths into a plurality of fiber optic cables. Since the waveguide material of each cable exhibits anomalous dispersion of the optical emissions, large changes in group refractive index are provided as a function of the different wavelengths of the optical emissions. As a consequence, only small changes in the different wavelengths of the optical emissions produce large changes in the time delay of the different wavelengths of the optical emissions within a fixed length of the optical fiber cables. This apparatus and method produce sensitive angle of arrival determinations for RF signals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.