Acousto-optic tunable filter control apparatus automatically adjusting frequency and power of radio frequency signal
AssigneeFujitsu Limited
InventorsMasaji Noguchi, Tomohiro Ueno, Goji Nakagawa, Yutaka Kai
Life of this patent
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Abstract
An AOTF control apparatus, which applies an RF signal to an AOTF to allow a selected light to pass through the AOTF, includes: a first calculating unit calculating a relationship between a frequency of the RF signal and a wavelength of the selected light based on a frequency of the RF signal that allows a reference light to pass through the AOTF; and a second calculating unit calculating a relationship between a power of the RF signal and an attenuation amount of the selected light based on an input/output power of the reference signal at the input/output of the AOTF.
Claims14
An acousto-optic tunable filter (AOTF) control apparatus that applies a radio frequency (RF) signal to an acousto-optic tunable filter (AOTF) to allow a selected light included in a wavelength-division multiplexing (WDM) transmission signal to pass through the AOTF to be dropped from the WDM transmission signal, comprising:
- a first calculating unit that calculates a relationship between a frequency of the RF signal and a wavelength of the selected light based on a frequency of the RF signal that allows a reference light of a predetermined wavelength to pass through the AOTF;
- and
- a second calculating unit that calculates a relationship between a power of the RF signal and an attenuation amount of the selected light based on an input power of the reference signal at the input of the AOTF and an output power of the reference signal at the output of the AOTF.
A control method of an acousto-optic tunable filter (AOTF) by applying a radio frequency (RF) signal to the AOTF to allow a selected light included in a wavelength-division multiplexing (WDM) transmission signal to pass through the AOTF to be dropped from the WDM transmission signal, comprising:
- calculating a relationship between a frequency of the RF signal and a wavelength of the selected light based on a frequency of the RF signal that allows a reference light of a predetermined wavelength to pass through the AOTF;
- and
- calculating a relationship between a power of the RF signal and an attenuation amount of the selected light based on an input power of the reference signal at the input of the AOTF and an output power of the reference signal at the output of the AOTF.
An apparatus comprising:
- an acousto-optic tunable filter (AOTF) array comprising a plurality of AOTFs, one of the AOTFs being a reference AOTF;
- the reference AOTF having an input at which the reference AOTF inputs a wavelength division multiplexed (WDM) signal and a reference signal, wherein a radio frequency (RF) signal applied to the reference AOTF causes a selected light included in the WDM signal to pass through the reference AOTF;
- a first calculating unit calculating a relationship between a frequency of the RF signal and a wavelength of the selected light that allows the reference light to pass through the reference AOTF and thereby be output from an output of the reference AOTF;
- and
- a second calculating unit calculating a relationship between a power of the RF signal and an attenuation amount of the selected light by the reference AOTF based on an input power of the reference signal at the input of the reference AOTF and an output power of the reference signal at the output of the reference AOTF,
- wherein the apparatus controls at least one of a temperature of the AQTF array, attenuation amount of the AOTF array, or power of the RF signal applied to the reference AOTF in accordance with the calculations.
Dependencies are inferred from the claim text.