Free-space optical communications system transmits 10.7 Gbit/s

Nov. 1, 2008
Scientists at Discovery Semiconductors (Ewing, NJ), Science Applications International (Albuquerque, NM), the Air Force Research Laboratory (Kirtland AFB, NM), and Schafer (Albuquerque, NM) have created a satellite free-space optical communications system that transmits 10.7 Gbit/s at 1.55 µm wavelength

Scientists at Discovery Semiconductors (Ewing, NJ), Science Applications International (Albuquerque, NM), the Air Force Research Laboratory (Kirtland AFB, NM), and Schafer (Albuquerque, NM) have created a satellite free-space optical communications system that transmits 10.7 Gbit/s at a 1.55 µm wavelength; with a commercial +37 dBm optical-booster amplifier, it would do so over a distance of several tens of thousands of kilometers. The receiver—the key development—is preamplified and has an optical-delay interferometer and a balanced photoreceiver.

The transmitter-receiver pair is based on return-to-zero differential phase-shift keying. The receiver has a sensitivity of 27 photons per bit at 10.7 GHz, less than 1 dB from the quantum limit of 22 photons/bit, resulting in a bit-error rate of 1 × 10-9. The photodetector is integrated with a clock-and-data recovery (CDR) unit to allow bit-error-rate measurements. To simulate Earth-to-satellite links, the system was tested with a “turbulence box,” containing heating elements and fans, which showed that even under heavy scintillation, the CDR locked onto the data stream, and also confirmed that the return-to-zero format was more robust than a non-return-to-zero format. Contact Christoph Wree at [email protected].

Sponsored Recommendations

Melles Griot® XPLAN™ CCG Lens Series

March 19, 2024
IDEX Health & Science sets a new standard with our Melles Griot® XPLAN™ CCG Lens Series fluorescence microscope imaging systems. Access superior-quality optics with off-the-shelf...

Spatial Biology

March 19, 2024
Spatial Biology refers to the field that integrates spatial information into biological research, allowing for the study of biological systems in their native spatial context....

Custom-Engineered Optical Solutions for Your Application

March 19, 2024
We combine advanced optical design and manufacturing technology, with decades of experience in critical applications, to take you from first designs to ongoing marketplace success...

Semrock Optical Filters Resources

March 19, 2024
Looking for more information about Semrock optical filters? Explore sets by fluorophore, download the 2023 Semrock catalog and more.

Voice your opinion!

To join the conversation, and become an exclusive member of Laser Focus World, create an account today!