Optical Spectrum Analyzer: CWDM
BaySpec’s CWDM optical spectrum analyzer (OSA) is an embedded, integrated monitor that delivers precise measurements and powerful processing capabilities to coarse wavelength division multiplexing (CWDM) applications.
CWDM combines up to 18 wavelengths into a single fiber. CWDM technology uses ITU standard 20 nm spacing between the wavelengths, from 1310 nm to 1610 nm. High reliability (GR-1209/1221 qualified) is achieved through a rugged mechanical design with no moving parts. Periodic calibration is not required. Input/output (I/O) is provided through a dual port RAM interface accessed through ADD/DAT bus direct connection or serial (RS232 or USB) communications.
The CWDM OSA employs a highly efficient volume phase grating (VPG®) as the spectral dispersion element and an ultra-sensitive InGaAs array detector, thereby providing high-speed parallel processing and continuous spectral measurement. As an input, the device uses a tapped signal from the main data transmission link through a single mode fiber, then collimates it with a micro lens. The signal is spectrally dispersed with the VPG®, and the diffracted field is focused onto an InGaAs array detector. The control electronics read out the processed digital signal to extract required information. Both the raw data and the processed data are available to the host through the chosen interface.