Circuit arrangement for optical frequency conversion

摘要

The switched input filter (EFA) incorporates a 1:n optical fibre switch (Sn) and a wavelength multiplexer/demultiplexer (DM) formed of a number of wavelength channel filters whose outputs are combined for transfer to a frequency converter (U) in the opposite direction to the modulated signal from a pumping laser (PL). This signal at a fixed frequency corresponds to a particular channel (k) of the input channel pattern (1-n). Output (A) is taken from the corresp. wavelength channel filter via a 2:1 selector (S2) affording a choice of the unconverted input signal from the corresp. switch fibre (sk).