Advantest Q8384

The Q8384 Optical Spectrum Analyzer can measure and evaluate ultra high-speed optical DWDM transmission systems, and optical components at high wavelength resolution and high accuracy. New high-end optical spectrum analyzer adopting a new four-pass monochromator system providing high wavelength resolution and wide dynamic range.

Exacting wavelength measurements are required of the optical source in DWDM optical communications. The Q8384 optical spectrum analyzer evaluates these specifications with
enhanced resolution bandwidth and wavelength accuracy.

The best in the world Q8384 achieves 10 pm wavelength resolution, and attains 20 pm wavelength accuracy in the 1550 nm band. This high performance makes it possible for the Q8384 to measure the oscillation wavelength characteristics of laser diodes accurately.

DWDM optical communication systems also contain wavelength division multiplexed
channels spaced at intervals as close as 50 GHz (0.4 nm). In this environment an optical spectrum analyzer with superior dynamic range is required to separate the optical signals and measure the noise figure (NF) of the optical amplifier.

The Q8384 has a dynamic range as wide as 50 dB at 0.1 nm and 60 dB at 0.2 nm and therefore fulfills these requirements adequately. Equipped with automatic optical amplifier NF measurement and arithmetic facilities, the Q8384 allows the user to make measurements in a simple fashion.

The Q8384 optionally has a built-in reference wavelength light source and an EE-LED (edge emitting LED). If the Q8384 is calibrated with this reference light source, the instrument is assured to provide wavelength accuracy of 20 pm in the 1550 nm band. Using the EE-LED's broad-band light source, the Q8384 allows the user to conveniently measure and evaluate the transmission and loss characteristics of narrow-band optical filters.

The Q8384 realizes a wavelength resolution bandwidth as highas 10 pm through the employment of a newly developed monochromator system. This makes it possible to measure and evaluate the side bands of optical signals which are intensity modulated at 10 Gbps, a task formerly impossible with conventional spectrum analyzers.

The Q8384 can measure wavelengths at an accuracy of ±20 pm within the wavelength range of the 1530 to 1570 nm C-band and at ±40 pm within the L-band range of 1570 to 1610 nm after being calibrated with the built-in calibration light source (option 25).

The Q8384 makes one button measurements of the noise figure with high accuracy possible through performance enhancements in dynamic range, polarization dependency, level accuracy, linearity, wavelength resolution setting accuracy, etc. and applying curve fitting and other functions.

The Q8384 can accurately determine the ASE level of DWDM signals that are multiplexed at intervals of 50 GHz (0.4 nm) or narrower, it provides not only the capability to perform accurate noise figure measurements but also the capability to show a listing of multiple measurement results at the same time.
The Q8384 can display a maximum of 256 peak wavelengths and power levels of WDM signals. It can show wavelength and power level as deviations from the ITU-T channel spacing or from a reference signal as well as in absolute values.

The Q8384 can show two sets of measurement data with different setup conditions in two windows. These windows are always rewritable using the alternate sweep function of the Q8384. With this function the user can make detailed measurements of signals in a specific wavelength band while monitoring the entire wavelength area of the WDM system.

The Q8384 supports long-distance transmission loop tests using an externally synchronized sweep function. It can measure very weak signals satisfactorily since it has a high sensitivity of approximately -65 dBm. Moreover, a pulse sweeping function makes it possible to measure a peak value of the measured light. Even pulsed light can be measured without missing any portion.

The Q8384 supports cascaded display of up to 32 traces, which allows the simultaneously display of multi-channel device characteristics such as from AWGs.

The Q8384 allows monitoring of DWDM systems. It is possible to continuously monitor whether the peak wavelength, the level of each channel and the SNR fluctuation are within their respective tolerances. It is also possible to simultaneously display the current values relative to the initial value, 1st channel value, and reference value as well as displaying the absolute value.

The Q8384 can simultaneously display the waveforms of the maximum value, minimum value, and current value of each measurement in repeated sweep. Display of the fluctuation range enables the user to understand at a glance the changes of the device characteristics against temperature and polarization
change.

The Q8384 can store data in TEXT and BITMAP formats with the built-in standard floppy disk drive.