Multimode fiber receiving circuit

Abstract

The invention relates to a high-sensitive multimode fiber receiving circuit. The high-sensitive multimode fiber receiving circuit is composed of a multimode fiber receiver, a high-speed operation amplifier and a high-speed comparator which are successively connected, wherein the output end of the multimode fiber receiver is connected with a same phase input end of the high-speed operation amplifier through a first-stage stopping condenser and a resistor bleeder circuit; the output end of the multimode fiber receiver is connected with a positive polarity input end of the high-speed comparator through a second-stage stopping condenser and a connecting power supply and the output end of the high-speed comparator is connected with a rear-stage logic circuit; another input end of the high-speed comparator uses middle power level of a working power supply; and when the transmission rate is 20Mbit / s, the optical fiber receiving sensitivity can be up to -30dB, if the speed rate reduces to be 10Mbit / s, and the optical fiber receiving sensitivity can be increased to be -33 dB. The transmission rate or the receiving sensitivity of the general multimode fiber receiving circuit has definite limitation, and when the distance of a send-receive end is relatively far, an error can exist, the general multimode fiber receiving circuit is not suitable for all application occasions.

Description

technical field [0001] The invention relates to a high-sensitivity multi-mode optical fiber receiving circuit, which is suitable for digital substations in electric power systems, intelligent substations, or digital power plants and wind farms. All intelligent primary equipment and networked secondary equipment for data exchange. Background technique [0002] Because optical fiber transmission has the advantages of high reliability, fast transmission speed, convenient wiring, and low cost, it is inevitable that optical cables replace most cables in intelligent substations, and more and more data exchanges use multimode optical fiber communication technology. [0003] Traditional multimode optical fiber communication generally adopts the following two schemes: one is the direct output of multimode optical fiber receiver with TTL output, although the receiving sensitivity can reach about -30dB, but the disadvantage is that the transmission rate cannot exceed 5Mbit / s; the other...

AI Technical Summary

Problems solved by technology

[0003] Traditional multimode optical fiber communication generally adopts the following two schemes: one is the direct output of multimode optical fiber receiver with TTL output, although the receiving sensitivity can reach about -30dB, but the disadvantage is that the transmission rate cannot exceed 5Mbit / s; the other is One is the multi-mode optical fiber receiver with analog output plus high-speed comparator. When the transmission rate is 10Mbit / s, the receiving sensitivity does not exceed -26dB. If the transmission rate increases to 20Mbit / s, the receiving sensitivity will drop to -23dB. The disadvantage is The transmission rate and receiving sensitivity cannot have both

The shortcomings of these two solutions have greatly limited the promotion and use of multimode fiber technology.

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