Summary of the technology
In high bit rate optical transmission, the use of a coherent homodyne receiver will largely increase the communication capacity and enhance the transmission performances. The proposed receiver is potentially large scale integrable, thus being useful for access network transceivers, and other applications which require low-cost and high performance receivers.
is to design a coherent receiver that can be implemented with simple elements and can be cost competitive to conventional systems, even for Fiber-to-the-Home access networks.
The proposed homodyne coherent receiver has two main parts: the first is a coherent balanced photo-receiver with added clock-synchronous phase switched (0-90º) local oscillator laser. The second part is an electronic post-processing performing the signal differential demodulation and a synchronous combination of the I&Q orthogonal components. This electronic post-processing can be implemented in both ways, analog and digital operations.
The local laser does not need to be phase-coherent with the incoming optical carrier, although an automatic wavelength controller is convenient to maintain the two wavelengths close each other. The local laser is directly modulated with the recovered clock signal.
Current stage of development
Experimental prototype and tests passed. Further information can be found at ECOC'07, paper 7.2.5, Berlin, Sept. 2007; and OSA Optics Letters, vol. 34, no. 4, Feb. 2009.
Applications and Target Market
Optical transceiver manufacturers Broadband Telecom System Integrators Optical Communication networks: transport, metropolitan, access
Reduces the optical channel spacing from 50 GHz to few GHz, enabling the allocation of a high number of WDM channels (> x10) in a single fiber.
Highly tolerant to phase noise, allowing the use of standard DFB lasers.
Avoids the use of the complex optical 90º hybrid.
Low cost implementation, photonically integrable.
Allows the use of advanced modulation formats, as xPSK.
Increased bandwidth x distance reach Improved dynamic margin when used as PON receiver. Ideal for long-reach PONs.
Intellectual property status
Technology available for licensing, transfering and technical cooperation Patent Status Granted
Universitat Politècnica de Catalunya - UPC
Technology Transfer Office