Design of an Optical-Fiber Transmission System for Astronomical Images

Some data transmission modes,such as camera-link,GIGE,LAN,optical-fiber,and other wide-bandwidth systems are widely used in astronomy because of a large quantity of information in astronomical images.Based on a project of astronomical CCD camera,we develop a special transmission system using optical fibers.By using this optical-fiber transmission system,astronomical images can be transmitted reliably and effectively.This paper first presents a general design of the system, then describes the designs of the FPGA peripheral circuit, the coding circuit,the decoding circuit,the optical transmission/receiving circuits,and the FPGA internal logic circuits at the transmitting and receiving terminals.The paper further describes some key devices and their interconnecting circuits,and gives estimates about the bit error rate of the system.The design method of VHDL is also included.Simulations and measured waveforms of some key devices are finally presented.