Resources Contact Us Home
Browse by: INVENTOR PATENT HOLDER PATENT NUMBER DATE
 
 
Four level FSK optical signal transmission with optical decoding and direct detection










Image Number 3 for United States Patent #5105295.

Apparatus for optical transmission of first and second digital channels. Each digital channel has first and second signal levels. The appparatus has a tunable laser for emitting an optical output at optical frequencies corresponding to current levels. Current responsive to the signal levels of the two channels provides current levels to cause the laser to emit a first optical frequency when the first channel has a second signal level and the second channel has a second signal level, a second optical frequency when the first channel has a first signal level and the second channel has a second signal level, a third optical frequency when the first channel has a first signal level and the second channel has a first signal level, and a fourth optical frequency when the first channel has a second signal level and the second channel has a first signal level. An optical transmission medium is coupled to the output of the laser. A tunable optical filter is coupled to the optical transmission medium. The filter is tuned to pass a pair of adjacent optical frequencies corresponding to a signal level on a selected channel. A baseband detector at the output of the optical filter for provides a mark when either of the pair of optical frequencies passes through the optical filter. The mark is indicative of a signal level on the selected channel.








 
 
  Recently Added Patents
Image processing apparatus
UV liquid treatment system
Method for isomerisation of hop alpha-acids using heterogeneous alkaline earth metal based catalysts
Methods, systems, and computer-readable media for providing an event alert
Enterprise seamless mobility
Tools and methods for yield-aware semiconductor manufacturing process target generation
Lead frame array package with flip chip die attach
  Randomly Featured Patents
Liquid applicator with a mechanism for fracturing multiple ampoules
Pie making toy
Method of evaluating lifetime of semiconductor material and apparatus for the same
Systems and methods to convert signals multiplexed on a single wire to three wire
Footstool
Truck cab body
Direct determination of the maximum grip coefficient on the basis of measurement of the circumferential extension in a sidewall of a tire
Signal receiving coil device for MRI apparatus
Preparation of stable graphite
2,4-dichloro-5-nitro-thiazole