DEVICE FOR EVALUATING SIGNAL TRANSMISSION PERFORMANCE OF OPTICAL COMMUNICATION EQUIPMENT

摘要

Evaluation of signal transmission performance of optical communication equipment used for optically communicating the signals for controlling general industrial machinery such as press machine. When a current within a predetermined range of magnitude is stepwisely supplied to a light-emitting element (33) of an optical transmission link (3), a frame signal including a current code that represents the magnitude of current fed to the light-emitting element (33) is sent from a transmitter (10) to a receiver (20) via an optical fiber (5). The receiver (20) detects communication errors based on an error check code in the frame signal sent from the transmitter (10). Based on both the content of current code in the frame signal and the result of error detection, the receiver determines the range of magnitude of current for the light-emitting element, within which no error may occur. The transmitter (10) varies the magnitude of current supplied to the light-emitting element (33) and detects the magnitude. Upon receipt of frame signal, the receiver (20) inspects the error check code in the frame signal to detect the communication error, and a range of magnitude of supply current that does not generate communication error is judged from the result of detecting communication error and the result of detecting current supplied to the light-emitting element (33).