Low Latency Fiberoptic Video & Data Link

Task:

Transport data such as motor control and 3D object coordinates across a fiber optic links that is shared with a W-UXGA loss less video link. Due to the interactive nature of the system, it is important that the 3D data arrives with minimal latency.

Challenge:

The usual approach to pack data into the vertical interval of the video link was not suitable as it would have introduced a minimum latency of 16.6 milliseconds which was deemed to high.  

Solution:

An FPGA allowed us to define a proprietary packet structure which was embedded in a standard aurora protocol. The proprietary packet structure allocated a fixed amount of BW to each of the sub channels (video, various independent data links & audio) in each transmission frame. Since more than four hundred and eighty thousand frames per second are transmitted, the latency for any data transmission is just over 2 microseconds

Technologies in use:

Xilinx Virtex6, SFP+ transceiver, Aurora core, custom VHDL coding