KEYWORDS: Free space optical communications, Optical testing, Signal detection, Free space optics, Telecommunications, Signal processing, Signal to noise ratio, Prototyping, Transmitters, Optical communications
Multi-point free space optical communication (FSOC) has been identified as a valuable and promising technology for meeting high-capacity and -density demands of future space and terrestrial communication networks. FSOC’s point-topoint nature has boosted extensive research on technologies and methods that support multi-user optical networks. An FSOC system platform is essential for fully characterizing, testing, and evaluating state-of-the-art, multi-user prototypes and technologies developed by both businesses and academic communities. This paper presents an experimental FSOC testbed that demonstrates next generation FSO systems and allows cognitive, multi-point communication. These systems provide a significant improvement over those with currently hampered with single-user limitations. The FSOC testbed is multi-node, modular, and high-speed with real-time ability to test O-PHY modules and O-MAC schemes. The testbed consists of multiple, independently tunable optical transmitters and receivers that can be configured to emulate various communication scenarios (e.g., point-to-point (P2P), point-to-multipoint (P2MP), and multi-point-to-multipoint (MP2MP). At the receiver side, a cognitive controller performs real time, blind processing of received signals for identifying the number of concurrent transmissions. Accordingly, the controller drives an optical switch to route detected signals to pre-defined paths. Given that a single-user transmission is detected on multiple paths, diversity combining will be performed to improve received signal-to-noise ratio (SNR). If multiple-user transmissions are identified, signals are routed into separate high-speed photodetectors for processing. The work described below details hardware components integrated in the platform, as well as software development for the cognitive controller. Furthermore, this work provides an experimental demonstration of the testbed capabilities for single-user and multiple-user scenarios.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.