• Download Catalogue| Chinese| ENGLISH| РУССКИЙ РУССКИЙ
  • Download Preview
  • FAQ

    What is a DWDM used for?

    Similar to CWDM’s mentioned in questions 3 and 4 DWDM’s are used to increase the amount of information or systems that can be transmitted over a single fiber. The DWDM’s will allow for many more channels using much tighter channel spacing. Typical DWDM’s will allow for but not limited to 32, 40 and 44 channels, while the 50GHz spacing will double that and allow for 64, 80 and 88 channels. 

    What is a DWDM?

    DWDM stands for Dense Wavelength Division Multiplexer. DWDM’s allow you to multiplex or demultiplex more than one wavelength over one fiber similar to the CWDM mentioned in questions 3 and 4. The word “Dense” is referring to the very narrow channel spacing measured in Gigahertz (GHz) as opposed to nanometer (nm). 

    DWDM’s typically use channel spacing of 100GHz with a working channel passband of +/-12.5GHz from the wavelengths center. This allows you to add multiple wavelengths on to one fiber within the 1550nm band which are wavelengths between approximately 1525nm–1565nm (C band) and/or 1565nm–1625nm (L band) adhering to the DWDM ITU-T G.694.1 frequency grid. 

    DWDM’s will also use 200GHz spacing essentially skipping every other channel in the DWDM grid. They have also gone one step further using an Optical Interleaver to get down to 50GHz spacing doubling the channels capacity from 100GHz spacing.


    What is a CWDM used for?

    Fiber Optic CWDM’s are used to increase the amount of information or systems that can be transmitted over a single fiber. They are also used to create virtual fiber or fiber relief freeing up existing fibers to be used for other networks or systems.

    For example a typical 4 channel CWDM point to point network will use a multiplexer to combine four different wavelengths onto one fiber and a demultiplexer at the opposite end to individually demultiplex or separate the wavelengths. This allows you to simultaneously transmit four different signals/systems over the same fiber. This would free up 3 other fibers on a four fiber network creating virtual fiber or fiber relief. 


    What is a CWDM?

    CWDM stands for Course Wavelength Division Multiplexer. CWDM’s work similar to the WDM’s explained in questions 1 and 2. “Course” meaning the channel spacing is 20nm with a working channel passband of +/-6.5nm from the wavelengths

    center. This is tighter channel spacing than typical Wide Band Optic (WBO) WDM’s, which allows for more channels within the ITU CWDM grid. CWDM’s allow you to multiplex or demultiplex multiple wavelengths over one fiber. This is done by using light wavelength filters. 

    The filters only allow specific wavelengths of light to pass through the filter to a single fiber port and the remainder of the wavelengths are then reflected back to another separate fiber port. When used in a series or concatenated together this allows you to add multiple wavelengths on to one fiber. From 1270nm to 1610nm there are 18 individual wavelengths/channels separated by 20nm spacing. 


    What does CE marking mean?

    CE marking is a declaration by the manufacturer that the product meets all the appropriate provisions of the relevant legislation implementing certain European Directives. CE marking gives companies easier access into the European market to sell their products without adaptation or rechecking. The initials "CE" do not stand for any specific words but are a declaration by the manufacturer that his product meets the requirements of the applicable European Directive(s).

    共13记录上一页123下一页

    Shenzhen Sopto Technology Co., Ltd. All rights reserved