Coherent CO(2) laser communication system with modulable retroreflectors.

Area of Science:

• Optics and Photonics
• Telecommunications Engineering
• Laser Technology

Background:

• Free-space optical communication systems are crucial for high-bandwidth data transmission.
• Carbon dioxide (CO2) lasers offer potential for long-range optical communication due to their wavelength characteristics.
• Modulable retroreflectors are key components for enabling bidirectional communication in free-space laser systems.

Purpose of the Study:

• To develop and evaluate a coherent CO2 laser communication system for high-quality voice transmission.
• To assess the system's performance over a significant distance (24 km).
• To compare the system's signal-to-noise ratio (SNR) with traditional direct-detection approaches.

Main Methods:

• Development of a coherent CO2 laser transmitter and receiver system.
• Integration of modulable retroreflectors at a remote site.
• Field testing of the system over a 24 km communication link.
• Measurement and comparison of SNR for coherent versus direct-detection systems.

Main Results:

• Successful high-quality voice communication was achieved over a 24 km distance.
• The developed system demonstrated a potential range capability of up to 80 km.
• A significant improvement of 20 dB in SNR was observed compared to a direct-detection system.

Conclusions:

• The coherent CO2 laser communication system is a viable technology for robust, long-range voice transmission.
• The system's enhanced SNR provides superior performance in free-space optical communication.
• Further development could extend the system's application to higher data rate communications.