Before all are safety! - Laser safety
- What is this for device?
This test device is for the first in field test.
It can fast detect: optical power,
detect wavelenght (1310nm or 1550nm),
test link (if other side connected to SFP or media converter (MC)) 100/1000Mbps for one or two fibers link,
work as callibrated light source CW (continuous wave) or modulated.
- How does it works?
The thest decice have 3 optical ports,
First port for optical power, wavelenght and link tester
Connected optical power goes through PLC splitter (Planar Lightwave Circuit) 1/2 with 50/50% insertion loss (what is approximately ≤4.0dB) to FWDM (Filter Wavelength Division Multiplexer) and to the 1x4 opto-mechanical switch (next OMswitch). By default OMswitch switched to the port which is not connected, to prevent SFP failure if obtained hight optical power. FWDM splits signals to 1310nm and 1550nm and each splitted signal connected to the InGaAs photodiode. Each photodiode connected to microcontroller throught OpAmps.
So when microcontroller detects signal from one of photodiodes and if this signal will not be higher as -2dBm, microcontroller will switch OMswitch to defined SFP 1310 or 1550 or 2fiber (if detected signal will be from 1550nm photodiode - will be switched to 1550 SFP, if detected from 1310nm - will be switched first to the 1310 or to 2 fiber SFP).
Next step is detecting link speed (if other side connected to SFP or to MC). This stage are realised throught integrated into SFP DDM (Digital Diagnostic Monitoring). DDM can show us not only tranceiver temperature, supply voltage, laser bias current, transmited average optical power, recieved optical modulation amplitude (OMA) or Average Optical Power, but also by received code detect link speed and identificate SFP or MC connected at the other end of the fiber.
Second port, tx port
This port is for 2 fibers SFP tx link testing. On display will be showed when received signal is 1310nm and microcontroller through 1310 SFP DDM will receiv identification information what other side SFP or MC use 2 fiber link, microcontroller will switch OMswitch to it's 5-th port and wait for connectind second (TX) optical fiber for link testing.
Third port, optical laser source
Wery often need to determinate/identificate correct fiber port in ODF (optical distribution frame). The laser source can work in 1310/1550nm and can be switched to CW or as modulated with different modulation frequency.
- Which specifications it can support?
The Device can messure high optical power from -50 up to ~+26dBm (Safety Class 1M)
Display resolution 0.01dB
Frequency Indentification Range <10KHz
Stabilized laser source 1310/1550nm (switchable) with output Power -7dBm to 0dBm (Safety Class 1)
Modulation Frequency: CW / 270Hz / 1KHz / 2KHz
- Why I (and others) need it?
This Power Meter can help to fiber optic technicians and other persons who working with fiber optics links, to identificate fiber, test links and determinate configurated link speed, identificate other side installed transcievers...
- What else I want to integrate in?
Else in my "every day working" I'm using VLS for fiber identification and fault location.
And I'm thinking about module which can determinate CATV 1310/1550nm signals.
Ideas and commensts are welcome ;)