direct modulation


Also found in: Acronyms.

direct modulation

In optical networking, generating the modulated signal by varying the current that creates the laser emission. Direct modulation is used for transmission speeds up to 2.5 GHz or higher speeds for short distances. Contrast with external modulation.
References in periodicals archive ?
Dry--etched short--cavity ridge waveguide MQW lasers suitable for monolithic integration with direct modulation bandwidth upto 3 GHz and low drive currents.
Study 2 will use functional magnetic resonance imaging to test the hypothesis that the non-motivational effect of interest on learning is produced by the direct modulation of striatal reward system in the hippocampal memory system.
Optical light sources with direct modulation (irrespectively on source type) were more tolerable for in-band crosstalk penalty compared with an externally modulated DFB-LD source [11].
These include antioxidant and anti-inflammatory properties as well as direct modulation of signalling pathways relevant for neurodegeneration.
The direct modulation scheme is simple but suffers from a laser--frequency chirp effect, this chirp effect results in severe degradation of the RoF system performance.
The IP also provides carrier and image suppression when used with direct modulation schemes.
Sumitomo Electric Industries Ltd, a leader in optical solutions, has announced that it is expanding its 10 Gbps portfolio with the introduction of an integrated direct modulation laser diode (DML) and a built-in electronic dispersion compensation (EDC) feature for use in 80 km transceivers.
One limitation in pursuing direct modulation architectures for future wide-bandwidth-generating designs is the low knee frequency exhibited by devices that target this approach.
This article focuses on a special phase-locked loop (PLL) module used in a W-CDMA mobile terminal with an RF direct modulation transmitter and a superheterodyne receiver.
These include inhibition of gastric secretions, which would slow digestion; enhancement of nitric oxide synthesis, which could alter insulin-stimulated glucose uptake; and direct modulation of insulin secretion.
2+] release from intracellular stores) and by direct modulation of calcium conductances, or indirect modulation of other ionic conductances which results in transmembrane hyperpolarization.
In the direct modulation experiment Alan Gnauck of AT&T Bell Labs in Holmdel, N.

Full browser ?