A laser transmission system includes: a modulation module, a voltage-current conversion module, an electro-optic conversion module, an optic-electro conversion module, and a control module. The modulation module is configured to modulate an input voltage, and output a first voltage. An average value of the first voltage within a first duration is 0. The voltage-current conversion module is configured to output a first current based on the first voltage. The electro-optic conversion module is configured to output an optical signal corresponding to the first current. The optic-electro conversion module is configured to receive the optical signal from the analog optical fiber, and output a second voltage based on the optical signal. The control module is configured to determine an average value of the second voltage, and determine an electro-optic conversion coefficient of the electro-optic conversion module based on the average value of the second voltage.
H04B 10/00 - Systèmes de transmission utilisant des ondes électromagnétiques autres que les ondes hertziennes, p. ex. les infrarouges, la lumière visible ou ultraviolette, ou utilisant des radiations corpusculaires, p. ex. les communications quantiques
H04B 10/25 - Dispositions spécifiques à la transmission par fibres
A signal transmission system includes a first laser signal transmission system, a second laser signal transmission system and a control module. The first laser signal transmission system includes an electric signal generation module, a first electro-optical conversion module and a first optical-electro conversion module. The electric signal generation module outputs a first current and a first voltage. The first electro-optical conversion module outputs a first optical signal. The first optical-electro conversion module outputs a second voltage. The second laser signal transmission system alternately inputs the first voltage and a calibration voltage and outputs a third voltage. The control module determines the first voltage based on the correspondence relationship between the calibration voltage and the third voltage and based on the third voltage, and determines a first electro-optical conversion coefficient based on a ratio of the first voltage to the second voltage.
H04B 10/80 - Aspects optiques concernant l’utilisation de la transmission optique pour des applications spécifiques non prévues dans les groupes , p. ex. alimentation par faisceau optique ou transmission optique dans l’eau
The application provides an attenuator and a differential voltage probe, comprising a forward attenuation circuit and a reverse attenuation circuit which are symmetrical with each other, a first compensation unit and a third compensation unit which are symmetrical with each other, a second compensation unit and a fourth compensation unit which are symmetrical with each other, and a differential amplifier; the four compensation units are all adjustable capacitor units composed of constant capacitance; a positive-going signal to be tested is attenuated by the forward attenuation circuit, and frequency characteristics of a preset frequency point are adjusted by the first compensation unit and second compensation unit; a negative-going signal to be tested is attenuated by the reverse attenuation circuit, and frequency characteristics of a preset frequency point are adjusted by the third compensation unit and fourth compensation unit; finally, the difference value is calculated by the differential amplifier, amplified and output.
The invention provides a signal isolation and transmission device, comprising a high-frequency amplitude modulation circuit, a signal demodulation circuit, a first H-field antenna and a second H-field antenna. The first H-field antenna and second H-field antenna are both loop antennas with an external conductive shielding layer, and an insulating layer is wrapped outside the conductive shielding layer. The annular parts of the first H-field antenna and second H-field antenna face and abut each other. The high-frequency amplitude modulation circuit is connected with a pin of the first H-field antenna, and a pin of the second H-field antenna is connected with the signal demodulation circuit. The signal to be tested is modulated onto a high-frequency carrier signal by the high-frequency amplitude modulation circuit, and then isolated and transmitted by the two H-field antennas, which greatly improves the anti-interference effect, reduces the attenuation degree and improves the coupling degree of the signals.
The application provides a closed loop current transformer, in which a hall element is positioned in a notch of a magnetic ring and is used for generating an induced voltage according to the magnetic field generated in the magnetic ring by current to be measured. A first compensating coil and a second compensating coil are wound on opposite sides of the magnetic ring in the same winding direction. An input end of the power amplifier circuit is connected with an output end of the hall element, and an output end is connected with the first compensating coil and the second compensating coil respectively. The other ends of the first compensating coil and the second compensating coil are respectively connected with a signal detection circuit, and an output end of the signal detection circuit is used as an output end of the closed loop current transform.
G01R 15/18 - Adaptations fournissant une isolation en tension ou en courant, p. ex. adaptations pour les réseaux à haute tension ou à courant fort utilisant des dispositifs inductifs, p. ex. des transformateurs
G01R 15/20 - Adaptations fournissant une isolation en tension ou en courant, p. ex. adaptations pour les réseaux à haute tension ou à courant fort utilisant des dispositifs galvano-magnétiques, p. ex. des dispositifs à effet Hall
G01R 19/00 - Dispositions pour procéder aux mesures de courant ou de tension ou pour en indiquer l'existence ou le signe
H03F 3/20 - Amplificateurs de puissance, p. ex. amplificateurs de classe B, amplificateur de classe C
An attenuator and a differential voltage probe. The attenuator comprises a positive attenuation circuit (10) and a negative attenuation circuit (20) which are symmetrical to each other, a first compensation unit (30) and a third compensation unit (50) which are symmetrical to each other, a second compensation unit (40) and a fourth compensation unit (60) which are symmetrical to each other, and a differential amplifier (70). The first compensation unit (30), the second compensation unit (40), the third compensation unit (50), and the fourth compensation unit (60) are all adjustable capacitor units constituted by constant value capacitors. A positive signal to be tested is attenuated by the positive attenuation circuit (10), and the frequency characteristic of a preset frequency point is adjusted by the first compensation unit (30) and the second compensation unit (40). A negative signal to be tested is attenuated by the negative attenuation circuit (20), and the frequency characteristic of a preset frequency point is adjusted by the third compensation unit (50) and the fourth compensation unit (60). Finally, the difference is calculated by the differential amplifier (70), and is amplified for outputting. The problems in the prior art of poor stability of the attenuator and the distortion of the measurement result of the differential voltage probe are effectively solved.
An isolated signal transmission apparatus, comprising a high-frequency amplitude modulation circuit (10), a signal demodulation circuit (20), a first magnetic field antenna (30), and a second magnetic field antenna (40). Both the first magnetic field antenna (30) and the second magnetic field antenna (40) are loop antennas each provided with a conductive shielding layer, the conductive shielding layer is covered with an insulating layer, and loop parts of the first magnetic field antenna (30) and the second magnetic field antenna (40) are opposite to each other and close to each other. The high-frequency amplitude modulation circuit (10) is connected to a pin of the first magnetic field antenna (30), and a pin of the second magnetic field antenna (40) is connected to the signal demodulation circuit (20). A signal to be measured is modulated to a high-frequency carrier signal by the high-frequency amplitude modulation circuit (10), and then subjected to isolated transmission by the magnetic field antennas which are opposite to each other and close to each other; thus, the anti-interference effect is greatly improved, the attenuation degrees of received and transmitted signals are reduced, and the signal coupling degree is improved.
Provided in the present invention is a closed-loop current transformer. A Hall component is arranged in a notch of a magnetically attractive ring and is used for generating an inductive voltage on the basis of a magnetic field generated in the magnetically attractive ring by a current to be measured; a first compensation coil and a second compensation coil are wrapped on either of opposite sides of the magnetically attractive ring in a same wrapping direction; a power amplifier circuit is connected at an input end to an output end of the Hall component and is connected at an output end respectively to the first compensation coil and the second compensation coil; the other end of the first compensation coil and that of the second compensation coil respectively are connected to a signal detection circuit; and an output end of the signal detection circuit serves as an output end of the closed-loop current transformer. By means of the closed-loop current transformer provided in the present invention, a positive compensation current outputted by a positive power supply and a negative compensation current outputted by a negative power supply can be used simultaneously to drive the compensation coils to generate superimposable magnetic fields, effectively solved is the problem of a heavy load on a power supply found in the prior art in which a single-side power supply is relied on to output a compensation current, and the detectable range of currents to be measured is broadened.
brevets
