摘要:
It is an object of the present invention to provide a DSB-SC system capable of suppressing a third order component. The DSB-SC modulation having high extinction ratio can be realized by adjusting the first order component, which is generated by applying a modulation signal (3fm), and the third order component, which is generated by applying a basic signal (fm), to have reversed phase and the same intensity level, and then by applying the first order component to the third order component, these two components cancel each other.
摘要:
In order to provide a reciprocating optical modulation system capable of obtaining a broad bandwidth, a reciprocating optical modulation system (1) of the present invention is basically provided with an optical modulator (2) modulating an output light by controlling one of an intensity, a phase and a frequency of an input light; a first fiber grating (3) transmitting a light of a predetermined frequency domain among lights inputted to and outputted from the optical modulator while reflecting lights of other frequencies; a second fiber grating (4) transmitting a light of a predetermined frequency domain among lights inputted to and outputted from the optical modulator while reflecting lights of other frequencies; and a signal source (5) generating a modulating signal to be inputted to the optical modulator (2).
摘要:
It is an object to provide an optical frequency control device or the like which can quickly carry out control over a wide frequency range. The object is achieved by an optical frequency control device or the like comprised of an optical SSB modulator (2), a bias voltage source (3) for applying a bias voltage to the optical SSB modulator (2), and a modulating signal source (4) for applying a modulating signal to the optical SSB modulator (2), wherein the modulating signal source (4) is provided with an arbitrary waveform generator (5) for generating an electrical signal with an arbitrary waveform, and an electrical signal multiplier (6) for multiplying a frequency of the electrical signal generated by the arbitrary waveform generator (5).
摘要:
It is an object of the present invention to provide a method and a device for automatically calibrating a light intensity measurement device. The device (1) includes an optical switch (3) for switching a route of output from an optical intensity modulator (2), an optical attenuator (5) arranged on a first waveguide (4), a second waveguide (6), a light intensity measurement device (7), a control device (8) for receiving light intensity information measured by the light intensity measurement device (7) and controlling the signal to be applied to the optical intensity modulator (2), and a signal source (9) for receiving a control signal of the control device (8) and adjusting the signal to be applied to the optical intensity modulator (2).
摘要:
It is an object of the present invention to provide an optical modulator which is capable of adjusting optical intensity of optical signals which contains non-desired components so that the intensity of the components become at a similar level, whereby the optical modulator is capable of effectively suppressing the non-desired components when the optical signals are combined.
摘要:
It is an object of the present invention to provide an optical modulation system capable of suppressing a carrier component (f0) and a high order component (such as a second order component (f0±2fm)). The optical modulation system includes Mach-Zehnder waveguide (8), a first intensity modulator (9) provided on a first arm (4), a second intensity modulator (10) provided on a second arm (5), a first main Mach-Zehnder electrode (MZCA electrode) (13a), and a second main Mach-Zehnder electrode (MZCB electrode) (13b). Non-desired components propagating the respective arms are made to have reverse phase before optical signals are combined, whereby the optical modulation system is capable of suppressing the non-desired components when the optical signals are combined.
摘要:
A condenser lens is incorporated into the end portion of a magnetic field measuring apparatus including a magneto-optical crystal. Alternatively, the end portion of the magnetic field measuring device includes an optical fiber having a core diameter smaller than that of a normal single-mode optical fiber.
摘要:
Provided is a photoelectric conversion device having a simple structure including a plurality of end-face incident type photoelectric conversion cells. A plurality of dye-sensitized unit cells are disposed on folded faces of the metal sheet that is in a folded form. In these unit cells, a light which comes from a lateral end face of a stacked structure of each unit cell is photoelectrically converted. The manufacturing process of a soar cell is simplified in comparison with the case that a plurality of end-face incident type photoelectric conversion cells are merely placed in a plane.
摘要:
Switching characteristics in an SPDT switch are improved to reduce the rise delay in a low power slot following after a high power slot. Control terminals of an SPDT switch are respectively provided with backflow prevention circuits. The backflow prevention circuit is configured to have two transistors and a diode. In a transmission mode, for example, when a time slot where a high power passes through transistors is followed by a time slot where a low power passes through, the electric charges accumulated in the gates of the transistors are blocked. In the case where the transistors are in the OFF state, the electric charges accumulated in the gates of the transistors are immediately discharged to allow the transistors to be completely turned OFF.
摘要:
A wireless communication system has a first operation mode (GSM mode) for amplifying a phase-modulated high frequency signal with a high frequency power amplifier circuit and a second operation mode (EDGE mode) for amplifying a phase and amplitude-modulated high frequency signal with the amplifier circuit. The amplifier circuit has an input of a high frequency signal, with the amplitude and frequency being fixed in both the first and second operation modes, and operates by being controlled for the bias state of each amplifying stage in accordance with the output control signal produced by a control circuit based on the demanded output level (Vapc) and the detected output level (VSNS) so that the amplifier circuit performs signal amplification to meet the demanded output level.