How to test the performance of the optical module?

How to test the performance of the optical module? After installing the light module, testing its performance is an indispensable step. When the optical devices in the entire network system are supplied by a supplier, if the network system can work normally, there is no need to test the sub -assembly of the system separately.

However, the sub -components in most network systems now come from different suppliers. Therefore, the compatibility and interoperability of testing of optical devices, especially the optical modules, is very important. So how to test the compatibility of the light module? After reading this article, I think you will find the answer. We know that the light module is composed of a transmitter and a receiver. When the transmitter is connected to the receiver through the optical fiber, if the code rate of the entire system does not achieve the expected effect, is it the problem of the transmitter or the receiver? Maybe there are problems with the transmitter and the receiver.

In fact, the transmitter and receiver of the optical module will affect each other. Therefore, the standard of the light module is that any receiver can receive the light signal of the launcher from the worst performance. The light signal received by the worst performance receiver. The worst performance of the transmitter or receiver accurately defines the complicated job. If the receiver needs to receive a certain power to meet the requirements of the system error rate, then the power is the minimum transmitting power of the transmitter; if The receiver can only withstand a certain jitter capacity, then the jitter capacity is the maximum jitter capacity of the transmitter. Testing optical modules are generally divided into 4 steps (as shown below), mainly divided into tests for transmitters and receivers.

Transmitter test

When testing, you need to pay attention to the wavelength and shape of the waveform output waveform, as well as the jitter and bandwidth of the receiver. When testing the transmitter, you need to pay attention to the following two points:

1. The quality of the input signal of the transmitter must be good enough. In addition, the quality of electrical measurement must be confirmed through jitter measurement and eye diagram measurement. Eye map measurement is a common method for checking the output waveform of the transmitter, because the eye map contains rich information, which can reflect the overall performance of the transmitter.

2. The output light signal of the transmitter must be measured with optical quality indicators such as eye map testing, light adjustment amplitude and anti -light ratio.

3. Different from the test transmitter, the quality of the light signal must be poor enough when testing the receiver. Therefore, a light pressure eye diagram that represents the worst signal must be created. Measurement and light power tests are calibrated.

4. Finally, the electronic output signal of the receiver needs to be tested. There are three types of tests: the eye map test, so that the "eye" of the eye map can be opened. Eye map tests are usually shake testing by the depth of the error rate. Testing different types of jitter shake tracking and tolerance, testing the tracking of the internal clock recovery circuit