PHOTONICS technology provider New Focus has announced the addition of two new detector lines: high-gain 80-MHz balanced receivers and 3.5-GHz receivers, for datacom/telecom test and measurement.
Available from Lastek , the Models 18X7 80-MHz balanced receivers provide higher gain, thus better signal detection, for coherent heterodyne-detection applications, including doppler light detection and ranging -- or LIDAR, a laser radar -- which is used to explore the atmosphere, and optical coherence tomography, which is used for mapping sub-surface features such as in the human body.
The Models 159X 3.5-GHz receivers are ideal for fast, accurate, waveform measurements across all communications wavelengths from 450-1630nm, and across multiple communications protocols, including Gigabyte Ethernet, Fibre Channel, Xaui, and OC-48.
The new balanced receivers are ideal for picking out signals in a sea of noise. They work by subtracting the photocurrent from two well-matched photodetectors.
Common-mode noise that is present on both the reference and signal beams, such as laser-intensity noise, is cancelled out and does not appear as part of the signal.
Any imbalance between the photocurrents generated by the reference and signal detectors, however, is amplified. Available in both visible-wavelength and near-infrared models, these new receivers come with free-space or fibre-connectorised interfaces.
The new dc-coupled 3.5-GHz receivers come standard with a multimode 62.5-micron fibre input and are available with either a gallium-arsenide (GaAs) detector for wavelengths from 400-900 nanometres or an indium-gallium-arsenide (InGaAs) detector for wavelengths from 900-1650nm.
They are well suited for time-domain characterisations of 2.5-Gb/s components and extinction-ratio measurements, as well as for frequency-domain measurements.