1. The composition and principle of the transmission channel
The transmission channel of the optical module consists of an electrical signal input interface, a laser driver circuit, an impedance matching circuit, and a laser component TOSA.
Its working principle is to input the electrical interface of the transmission channel, couple the electrical signal through the electrical interface circuit, and then modulate it through the laser driving circuit in the transmission channel. Then, impedance matching is performed through the impedance matching part to complete the modulation and driving of the signal. Finally, it is sent to the laser (TOSA) for electro-optic conversion into an optical signal for optical signal transmission.
2. The composition and working principle of the receiving channel
The receiving channel of the optical module consists of a photodetector component ROSA (composed of photodetector diodes (PINs) and transimpedance amplifiers (TIAs)), an impedance matching circuit, a limiting amplification circuit, and an electrical signal output interface circuit.
Its working principle is that PIN converts the collected optical signal into an electrical signal in a proportional manner. TIA converts this electrical signal into a voltage signal and amplifies the converted voltage signal to the desired amplitude. The impedance matching circuit transmits the signal to the limiting amplifier circuit for further amplification and shaping, improving the signal-to-noise ratio and reducing the error rate. Finally, the electrical interface circuit completes the signal output.
