18 results about "Bias tee" patented technology

The invention provides a frequency stabilization device and method for any detuning frequency of a laser. The frequency stabilization device comprises a pumping laser atomic resonance point frequency stabilization structure, a cavity length locking structure of an optical resonant cavity and a frequency stabilization structure for detecting any detuning frequency of the laser. The frequency of the pumping laser is stabilized at an atomic resonance point through a saturated absorption frequency stabilization method, and then the cavity length of an optical resonant cavity is locked by taking the frequency-stabilized pumping light as a reference. Two modulation signals with different frequencies are superposed by adopting Bias Tee, biphase modulation is applied to detection laser through an electro-optic phase modulator, a stable error signal is demodulated while a modulation sideband is generated, then a first-order sideband is locked on a longitudinal mode, close to an optimal detuning point, of an optical resonant cavity, and a second-order sideband is locked on a longitudinal mode, close to the optimal detuning point, of the optical resonant cavity. Continuous frequency tuning in the laser frequency stabilization process is detected by adjusting the first-order sideband frequency. According to the invention, the size and the cost are reduced.

A non-interferometric thin film lithium niobate electro-optical modulator for data transmission including a laser, configured to generate an input continuous wave light beam; a non-interferometric thin film lithium niobate modulator including an optical waveguide situated along with the coplanar transmission lines and the DC bias conductors. The propagation constant of the optical waveguide is tuned and modulated by the RF data signal and the DC bias voltage traveling on the coplanar transmission lines and the DC bias conductors. The modulator can be tuned at quadrature point by the DC bias voltage. The optical power can be modulated by the RF data signal travelling on the coplanar transmission line; a low noise RF amplifier for data signal amplification; and a bias tee for combining the data signal and DC bias voltage and send them to the coplanar transmission lines.

This paper proposes a testing system for superconducting array single-photon detectors, comprising a test light source, a refrigerator, and a cryogenic readout circuit. This system can perform single-photon pulse response and spectral response tests in different wavelength bands, and is capable of variable-temperature testing under varying temperature conditions. The system utilizes a T-type cryogenic bias tee and cryogenic radio frequency amplifier to minimize the transmission attenuation of test signals, providing a novel approach for testing large-scale superconducting array detector chips. All components within the system are commercially available and, after optical path calibration and installation, can operate continuously and stably. This system is suitable for testing superconducting array single-photon detectors.

In the present invention, DAC by means of an R-2R ladder circuit is used in a variable resistance circuit 10b of a low frequency correction circuit 10 to control a control signal of the variable resistance circuit 10b, whereby it becomes possible to correct a low frequency signal component of a pulse signal attenuated in a transmission line from a pulse generator 110 to a bias tee 130 and to supply, to a quantum bit, a DC offset signal added by an addition circuit 10d of the low frequency correction circuit 10. Furthermore, by using the DAC by means of the R-2R ladder circuit in the variable resistance circuit 10b, it is possible to prevent the DC offset signal from changing even when the resistivity of the variable resistance circuit 10b is made to be variable.

The application provides a laser arbitrary detuning frequency stabilizing device and method, which comprises a pumping laser atomic resonance point frequency stabilizing structure, an optical resonant cavity length locking structure and a detection laser arbitrary detuning frequency stabilizing structure. The pumping laser is stabilized at the atomic resonance point by a saturated absorption frequency stabilizing method, and then the cavity length of the optical resonant cavity is locked by using the stabilized pumping light as a reference. Two different frequency modulation signals are superimposed by using a Bias Tee, and the detection laser is subjected to double phase modulation by an electro-optic phase modulator, so that a stable error signal is demodulated while the modulation sideband is generated. Then, the first order sideband is locked on the longitudinal mode of the optical resonant cavity near the optimal detuning point, and the frequency continuous tuning in the detection laser frequency stabilizing process is realized by adjusting the first order sideband frequency. The volume and cost are reduced.

To provide a communication device that can supply a DC voltage from a centralized power supply to an amplifier without applying a connector to the amplifier for directly supplying the DC voltage from the centralized power supply to the amplifier.SOLUTION: A communication device includes a bias tee that is connected to one end of a coaxial line whose other end is connected to a signal output terminal of a low-noise amplifier and that outputs a DC voltage to the low-noise amplifier via the coaxial line.SELECTED DRAWING: Figure 7

A test and measurement system includes a device under test (DUT) interface structured to couple to first and second DUTs that are coupled to form a half bridge circuit. A characterization circuit is controlled to perform static testing and dynamic testing of the first and second DUTs. The characterization circuit includes a solid-state bias tee including the first DUT and a first drive voltage generator that provides a DC pulse signal and AC signal on a gate node of the first DUT to cause the first DUT to supply current and voltage signals to the second DUT for static and dynamic characterization of the second DUT. One characterization circuit can generate, at the same time, the gate charge characterization parameters for one DUT and reverse current path (e.g., body diode) characterization of another DUT.

The invention provides a double-optical-comb signal optical frequency calibration system, and relates to the technical field of optical measurement. The system comprises a bias tee joint, a calibration signal generation module and a frequency resolving module, wherein the calibration signal generation module is composed of a laser, an optical loop and a double-optical-comb unit, and an optical reference signal and comb teeth of an optical frequency comb to be calibrated generate a radio frequency calibration signal in a beat frequency mode; and the frequency resolving module mixes the radio frequency calibration signal with the equidistant radio frequency reference signal generated by the comb signal generator through the mixer, and the optical frequency of the optical frequency comb to be calibrated is determined by the signal calculating unit in combination with the time domain pulse signal collected by the oscilloscope after the frequency is filtered by the band-pass filter. The optical frequency calibration device realizes high-precision and continuous-coverage optical frequency calibration of middle-infrared band double-optical-comb signals, is simple in structure and high in measurement precision, and is suitable for scenes of gas detection, environment monitoring, spectral analysis and the like.

The invention discloses a system for improving optical communication sensitivity, which comprises an optical transmitting module, an optical receiving module and a digital signal processing module, and is characterized in that the optical transmitting module is used for realizing direct-current equalization and dynamically adjusting Bias Tee direct-current bias according to an input signal, so that the peak-to-peak value of an output radio-frequency signal is V pi and is symmetrical about a zero level; the optical receiving module is used for converting an optical signal into an electric signal by the APD and converting an analog signal into a digital signal by the ADC; the digital signal processing module is used for recovering and demodulating the digital signal to obtain original information; and meanwhile, the theoretical receiving sensitivity of different duty ratios OOK-RZ can be speculated according to the condition of an optical communication system. According to the system and the method for improving the optical communication sensitivity provided by the invention, the extinction ratio of the optical signal output by the MZM modulator is improved; the sensitivity of an optical communication system can be effectively improved; and according to the condition of the optical communication system, the theoretical receiving sensitivity of different duty ratios OOK-RZ is speculated.

The application includes a test and / or measurement system having an RF signal source to generate an RF stimulus signal; a device port; a signal path connecting the RF signal source to the device port; a measurement unit coupled to the signal path to measure the RF stimulus signal propagating via the signal path to the device port and a measurement signal received at the device port. A bias tee couples to the signal path and includes a DC input port to receive a DC bias signal. The bias tee couples the DC bias signal into the signal path. The system operates in a calibration mode where at least four different calibration standards are alternately connected to the device port. The system couples the DC bias signal into the signal path during the connection of one or more of the calibration standard(s), but not with all of the calibration standards.

The present invention relates to a circuit arrangement comprising: a bias tee having an input AC terminal comprising a bias tee capacitor, wherein the input AC terminal is adapted to receive at least one AC signal, wherein the AC signal comprises at least one of a positive pulse train signal and a negative discharge pulse signal; an input DC terminal, adapted to receive at least one bias DC signal; and an output interface, adapted to output a signal based on the received AC signal and the received bias DC signal, and a discharge circuit, adapted to discharge the bias tee capacitor.

The invention discloses a beam longitudinal distribution measuring device and method, and the device comprises a signal generation unit, a bias three-way device, an electro-optic intensity modulator, a light transmitting unit, a light receiving unit, and a signal processing unit. The inner conductor of the Faraday cup is configured to generate a high-speed voltage signal when the charged particle beam bombards the inner conductor through the opening; the bias three-way device is used for transmitting a high-speed voltage signal; the electro-optic intensity modulator is used for receiving the high-speed voltage signal and an output light signal output by the light emitting unit and outputting a modulated light signal; the light receiving unit is used for receiving the modulated light signal and converting the modulated light signal into a modulated electric signal; and the signal processing unit is used for collecting the modulation electric signal, converting the modulation electric signal into a particle beam digital signal and displaying beam longitudinal distribution of the charged particle beam in real time. High-frequency signal distortion and signal-to-noise ratio reduction in the transmission process are prevented, and the precision of beam longitudinal shape measurement is ensured.

The present invention discloses a terahertz detector circuit structure based on a resonant tunneling diode, which belongs to the field of terahertz wireless communication. It comprises three parts: a resonant tunneling diode RTD, a low-pass filter and a biasing device BIASTEE. Among them, the resonant tunneling diode RTD acts as a nonlinear device to detect the received terahertz signal, the low-pass filter is mainly used to pass the detection signal and block the high-frequency carrier signal, and the biasing device BIASTEE is used for DC feeding and the passage of the detection signal. After adding a DC bias through the biasing device BIASTEE, the resonant tunneling diode RTD operates in the nonlinear region and detects and demodulates the received terahertz signal. The present invention has the advantages of simple structure, small size and low cost, and has important application value in the field of ultra-high-speed wireless communication.

A test and measurement system includes a device under test (DUT) interface structured to couple to first and second DUTs that are coupled to form a half bridge circuit. A characterization circuit is controlled to perform static testing and dynamic testing of the first and second DUTs. The characterization circuit includes a solid-state bias tee including the first DUT and a first drive voltage generator that provides a DC pulse signal and AC signal on a gate node of the first DUT to cause the first DUT to supply current and voltage signals to the second DUT for static and dynamic characterization of the second DUT. One characterization circuit can generate, at the same time, the gate charge characterization parameters for one DUT and reverse current path (e.g., body diode) characterization of another DUT.

Aspects of the subject disclosure may include, for example, a differential biasing device that includes first and second bias tees having respective high-frequency biased terminals, high-frequency unbiased terminals and biasing terminals. The first and second bias tees can be configured at least partially on and / or within different layers of a substrate to facilitate a compact configuration. The layers can include surface layers and / or internal layers that enable an overlapping of at least portions of the first and second bias tees. Other embodiments are disclosed.

The invention relates to a test and / or measurement system (10). The test and / or measurement system comprises: an RF signal source (11) configured to generate an RF stimulus signal; a device port (13); a signal path (12) which is arranged to electrically connect the RF signal source (11) to the device port (13); a measurement unit (15) which is coupled to the signal path (12), wherein the measurement unit (15) is adapted for measuring the RF stimulus signal propagating via the signal path (12) to the device port (13) and a measurement signal received at the device port (13); and at least one bias tee (14) which is coupled to the signal path (12), wherein the bias tee (14) comprises a DC input port which is configured to receive a DC bias signal, wherein the bias tee (14) is arranged to couple the received DC bias signal into the signal path (12). The test and / or measurement system (10) is operable in a calibration mode during which at least four different calibration standards (40a-d) are alternately connected to the device port (13). The test and / or measurement system (10) is configured to couple the DC bias signal into the signal path (12) via the bias tee (14) during the connection of at least one of the calibration standards (40a-d), but not during the connection of all of the calibration standards (40a-d).

The present invention relates to a radio frequency (RF) bias tee for superimposing a direct current signal on a RF signal, comprising: a dielectric layer; a first transmission line disposed on one surface of the dielectric layer so as to receive the RF signal; a second transmission line disposed on the other surface of the dielectric layer so as to receive the direct current signal; and a third transmission line which is vertically connected to the second transmission line so as to receive the direct current signal, and which is coupled to the first transmission line so as to receive the RF signal, thereby superimposing the RF signal and the direct current signal. Therefore, capacitance and inductance can be implemented without using an inductor and a capacitor, which are separate passive elements, thereby enabling the RF bias tee to be compact.