Some Structions of CWDM From FOCC
We all know that there is a type of WDM called CWDM, which has a 20 nm channel spacing. And the channel spacing is so wide because it is designed for non temperature controlled laser transmitters. The passbands for CWDM typically must be wide and flat with a bandwidth greater than 14 nm. The band multiplexer is a good way to make a CWDM de/multiplexer. The Figure show me that a waveguide a layout for an 8 channel cwdm multiplexer and the measured response. Because the channel spacing is so wide, the AWG grating orders are vary small and having unequal path lengths in the AWL, adds a negligible amount of chromatic dispersion (allowing one to use a “U” shape for the AWL, making it more compact). Thus, the AWGs take on a “W” shape, and the AWL takes on a “U” shape. A highly compact silica waveguide PLC 4 channel CWDM multiplexer made using a completely different technique, a two dimensional reflective hologram.
Transparent CWDM MUX/DEMUX EQUIPMENT is typically passive (not powered). Passive devices cannot generate or repeat optical signals. Additionally, IOAs operate in a small wavelength range that overlaps only three CWDM signals. Some CWDM signals are unaffected by IOAs, so each CWDM span must terminate at a distance determined by the unamplified signals. Therefore, no benefit is realized by amplifying any of the CWDM signals. This means that all optical signals loss introduces by CWDM mux/demux equipment, splices, connectors, and the fiber must be subtracted from the launch power of the colored GBIC/SFP installed in the client.
CWDM can be used by enterprise on leased dark fiber to increase capacity (for example, from 1Gbps to 8 Gbps or 16 Gbps) over metro area distance. One problem with CWDM is that the wavelengths are not compatible with erbium-doped fiber amplifier (EDFA) technology, which amplifies all light signals within their frequency range.
As for the fiber optical amplifier, we have a wide range of it, such as EDFA optical amplifier Booster Amplifier, CATV amplifier, In-line Amplifier, Booster Amplifier, WDM amplifier and so on, want to know more knowledge of it, you can visit into FOCC’s tutorial. Related product you can vist FOCC’s home page, you must find what you want.
Let me introduce our company, FOCC. it designs, manufactures, and sells a broad range of optical communication products, including passive optical network, such as the passive cwdm mux or optical splitter used in the enterprise, access, and metropolitan segments of the market, In particular, FOCC products include optical subsystems used in fiber-to-the-premise, or FTTP, deployments which many telecommunication service providers are using to deliver video, voice, and data services.