Advantest Q8331 Multi-Wavelength Meter

The Multi-Wavelength Meter model Q8331 is targeted at the growing market for DWDM (Dense Wavelength Division Multiplexing) backbone and metropolitan area networks. Designed for use in both R&D and production, the Q8331 enables quick and accurate simultaneous measurements of the emission wavelengths and power levels of up to 300 DWDM channels.

One of the ways in which optical engineers have been working to respond to the explosive growth in data traffic is by using DWDM to increase the number of transmission channels available within optic fibers. As a result, the latest DWDM systems now possess a capacity of up to 256 such channels. By raising this number, however, engineers are forced to narrow the spacing between adjacent channels, making it easier for neighboring pulses to interfere with each other. Thus, it becomes vital that engineers check and tune the wavelengths and power levels of individual channels to ensure that they are in exact compliance with specifications such as the ITU-T grid, a set of channels that are spaced at a set interval established by the International Telecommunication Union.

Features

Building upon the high standard established by the company's previous model Q8326, the Q8331 provides improved measuring accuracy, a faster measurement time of approximately 0.5s (twice the speed of conventional systems), and the ability to simultaneously measure a maximum of 300 channels.

• Measurable Wavelength Range 1270 nm to 1680 nm
  
• Wavelength Accuracy ±1 ppm (1.5 pm at 1550 nm)
  
• Display Resolution 0.1 pm
  
• Channel Power Accuracy ±0.5 dB (1310 nm, 1550 nm)
  
• Detection Sensitivity -40 dBm (1270 nm to 1600 nm)
  
• Max. Input Power +10 dBm
  
• Measurement Time 0.5 s (Interval between consecutive measurements)
  
• General Specifications Display - 6.5-inch color liquid crystal
  
• Dimensions - Approx. 424 mm (width) × 132 mm (height) × 500 mm (depth)
  weight 13 kg

Operation

Optical engineers will also find that the Q8331 makes it easier to monitor and tune wavelengths because its standard LCD display gives them the choice of viewing either actual wavelength fluctuations or their numerical equivalents. Another feature that will ease the burden of testing is the Q8331's pass-fail function, which will enable users to determine whether channel deviation (also known as drift) and other wavelength characteristics comply with the ITU-T grid, all without having to perform any complicated operations. The Q8331 is also well suited for measuring the gain, or amplification factor, of DWDM optical fiber amplifiers because it has a low gain flatness of ±0.2dB. It offers temperature and atmospheric pressure sensors, which monitor changes in the surrounding test environment and compensates wavelength readings accordingly.