62 results about "Bias tee" patented technology

A method of operating a cellular base station subsystem such as a smart bias tee. The method comprising: modulating a first control data signal to generate a first modulated carrier signal; multiplexing said first modulated carrier signal with a first RF antenna signal onto a feed line; demultiplexing a second RF antenna signal and a second modulated carrier signal from said feed line; demodulating the second modulated carrier signal to generate a second control data signal; analyzing at least one of said signals to generate diagnostic data; and outputting said diagnostic data. The subsystem also has an addressable memory adapted to provide data on request from said subsystem.

The invention discloses a device for achieving a minitype CPT atomic clock physical system. The device comprises a Bias-Tee, a VCSEL, a first quarter wave plate, an atomic gas chamber, a second quarter wave plate, a polarization beam splitter, a first photoelectric detector and a second photoelectric detector. The invention further discloses a method for achieving the minitype CPT atomic clock physical system. Elliptically-polarized light is adopted for resonance with atom CPT, and difference detection is conducted on the optical rotation effect generated by the resonance. According to the device and method for achieving the minitype CPT atomic clock physical system, background noise generated by optical frequency components which do not interact with atoms in multi-color light output by the VCSEL and conversion noise generated by light interacting with the atoms due to light frequency jitter which is converted into signal amplitude jitter through action with the atoms are eliminated, and the signal to noise ratio of CPT resonance signals is greatly increased; in addition, the device and the method further have the advantages that the influence on the obtained CPT resonance signals by environment magnetic field intensity fluctuation is small, and laser frequency stabilization can be easily achieved through an achieved atomic clock.

Accordingly, a preferred embodiment of the present invention comprises an electro-optical device having an optical waveguide that includes two optical pathways, wherein the optical waveguide is embedded within the substrate. A bias electrode layer is formed on the surface of the substrate. A buffer layer is formed on at least a portion of the bias electrode layer and the surface of the substrate. An RF electrode layer is formed on the buffer layer. A bias-tee electrically couples the bias electrode layer and the RF electrode layer.

A coefficient indicating the relationship between a measurement voltage of voltage measuring unit and a voltage drop in a drain bias voltage due to drain current is determined based on an S parameter of a bias tee and an input impedance of the measuring unit. A voltage drop at the drain is determined from the coefficient. Based on the determined voltage drop, a drain bias voltage actually applied to the drain of an FET is determined. Also, a coefficient for converting the measurement voltage of the measuring unit into a drain current is determined based on an S parameter of a two-terminal-pair network of the bias tee and the input impedance of the voltage measuring unit. Based on the determined coefficient, a drain current actually flowing in the FET is determined.

A miniature wideband bias tee that has a small package size. The bias tee has a low temperature co-fired ceramic substrate with a top surface and a bottom surface. A first inductor is located within the substrate. A second inductor is attached to the top surface and has a core with a wire wound on the core. Terminals are located on the top and bottom surfaces. Ends of the wire are connected to terminals on the top surface. A capacitor is mounted to terminals on the top surface. Several vias extend through the substrate and electrically connect the terminals to the inductor and capacitor.

Both a system and method for optically powering a network component, such as the transponder of a picocell, is provided. The system includes a vertical cavity surface emitting laser (VCSEL) for processing an input signal, a remotely-located optical power source, and an optical fiber for conducting optical power from the source to the VCSEL. The VCSEL may be electrically biased from current generated by an optical-electro converter coupled to the fiber, or directly optically biased from light from the optical power source. A bias tee is connected between an input signal and an input of the VCSEL such that the VCSEL generates a modulated optical signal. The system may be the transponder of a picocell system where the VCSEL generates an optical uplink signal conducted to a head-end circuit via the same or a separate optical fiber.

A load pull measurement setup allows independent impedance tuning at RF frequencies at the output of the DUT as well as independent tuning at RF and baseband frequencies of the modulated signal at the input of the DUT. This allows optimizing baseband frequency impedances for nonlinear amplifier performance when processing modulated signal, such as IMD, ACPR etc. Baseband tuning is done using a low frequency programmable impedance tuner, which is connected through the input bias tee, which acts as a frequency separator (diplexer). The input bias tee may be an LC based network or a 3 dB matched coupler based network.

The invention discloses a pulsed DC testing system and method of a GaN HEMT microwave power device. A vector network analyzer is used for testing the S parameter of the GaN HEMT microwave power device, or a semiconductor analyzer is used for testing the pulse direct current characteristic of the GaN HEMT microwave power device. The two output ends of the vector network analyzer or the semiconductor analyzer respectively load pulse radiation frequency signals to the grid electrode and the drain electrode of a tested GaN HEMT device through a Bias Tee. Two DC power supplies with different voltage grades are respectively loaded on two Bias Tees through two groups of switches. According to the pulsed DC testing system and method of the GaN HEMT microwave power device, when the GaN HEMT microwave power device is tested, pulse DC voltages are used, two groups of switch circuits control the DC power supplies applied on the Bias Tees to be connected, and the automatic heating phenomenon of the GaN HEMT and the performance deterioration of the microwave power device caused by continuously applying of the DC voltages on the GaN HEMT are avoided.

Bias tees, according to certain embodiments of the present invention, include switches in the AC signal path, the DC signal path, or both, to improve the capability of the bias tees to be used for high impedance AC measurement, low current DC measurement, or both. Optical control of the switches, as well as control of the switches using a DC bias present within the AC signal input to the bias tee, is described. Including a set of diodes into the DC signal path, rather than a switch, provides enhanced capability of the bias tee to be used for high impedance AC measurements.

Testing is performed on an amplifier wafer housing a transimpedance amplifier prior to packaging the transimpedance amplifier with an external photodetector, wherein the transimpedance amplifier includes a small, auxiliary, integrated silicon photodetector provided at the input of the transimpedance, in parallel with external photodetector attachment points. The small auxiliary photodetector does not significantly affect the high speed performance of the transimpedance amplifier. The small auxiliary photodetector is provided to facilitate wafer-level testing at the transimpedance amplifier input. To test the transimpedance amplifier, the transimpedance amplifier is stimulated by optically exciting the small auxiliary photodetector, wherein the small auxiliary photodetector is excited using short wavelength light, whereby advantages such as higher efficiency may be obtained. The testing method includes placing the amplifier wafer in a testing system, probing the power and ground connections on the amplifier wafer, illuminating the small auxiliary photodetector on the amplifier wafer, and detecting the output of the transimpedance amplifier housed on the amplifier wafer. The output of the transimpedance amplifier may detected by probing the supply voltage and detecting the switching currents passing through a bias tee using a spectrum analyzer, using a high gain antenna and a sensitive narrow band receiver, or using a high speed electrical probe.

The invention provides a transmission device of a DCO-OFDM visible light communication system. The transmission device comprises a pre-emphasis module, a digital-to-analog conversion module, a protection module, a filter, an amplitude attenuator, a power amplifier, a Bias-Tee and a constant current source module which are connected in sequence; a quantized digital signal is transmitted to the pre-emphasis module for digital pre-emphasis compensation operation; after that, the quantized digital signal is transmitted to the digital-to-analog conversion module to generate an analog signal; the overload pulse of the analog signal is absorbed by the protection module, the analog signal is filtered by a filter module, adjusted by an amplitude attenuator module, and subjected to power amplification by a power amplifier module; and a Bias-Tee module couples a bias current from the constant current source module and a signal from the power amplifier module, and then uses the coupled signal to drive an LED lamp to emit an optical signal. According to the transmission device of the DCO-OFDM visible light communication system provided by the invention, digital pre-emphasis compensation can becarried out on transmitted signals, LED frequency response characteristics can be optimized, and noises in DCO-OFDM baseband signals can be reduced.

A probe assembly including a probe, a waveguide to transmission path transition, and a bias tee detachably connected to the probe.

The invention belongs to the technical field of mobile communication electrically-tunable antenna control and discloses an electrically-tunable antenna control device integrated with a RAE (Remote Antenna Extension), a SBT (Smart Bias Tee) and a RCU (Remote Control Unit), which comprises an electrically-tunable controller, an antenna, a mounting guide rail and a back plate, wherein the mounting guide rail and the back plate are both arranged in the antenna; an RF port is arranged in the back plate; the RF port is used for accessing a feeder line; the electrically-tunable controller is detachably arranged in the antenna through the mounting guide rail; the electrically-tunable controller comprises a motor, an RCU module, an SBT module and an RAE module; and the RCU module is respectively connected with the motor, the SBT module and the RAE module. the electrically-tunable antenna control device provided in the invention integrates functions of the RAE device, the SBT device and the RCUdevice together, a condition of difficult antenna port layout can be avoided, and the device has the advantages of convenient construction and simple maintenance.

The invention provides a terahertz quantum cascade laser optical beat note signal detection system and method. The detection system includes: a terahertz quantum well detector which is intended for detecting a terahertz multi-mode laser ray which is transmitted by the terahertz quantum cascade laser and an optical beat note signal, and converting the converting the optical beat note signal to an electrical signal; an off-axis polished mirror group which is intended for converging terahertz multi-mode laser rays which are generated by the laser and guiding the terahertz multi-mode laser rays to the terahertz quantum well detector; a detector DC source which is intended for outputting a DC to the terahertz quantum well detector; a T-type bias tee which is intended for providing DC bias output by the detector DC source to the terahertz quantum well detector and coupling the optical beat note signal which is detected by the detector; an amplifier which is intended for amplifying the optical beat note signal which is coupled by the T-type bias tee; and a high-frequency detection apparatus which is intended for acquiring spectral characteristics of the optical beat note signal. According to the invention, the system can effectively represent the spectral characteristics of the terahertz quantum cascade laser optical beat note signal.

A RF and pulse bias tee for use with a source measure unit (SMU) includes a SMU source terminal; a SMU measure terminal; an output terminal; a SMU measure terminal pulse/RF block between the SMU measure terminal and the output terminal; a SMU source terminal high frequency block having two end nodes and an intermediate node, the end nodes being connected between the SMU source terminal and the output terminal; a RF input; a pulse/DC block between the RF input and the output terminal; a pulse input; and a DC block between the pulse input and the intermediate node.

The Invention comprises a method and Interface for powering and controlling an antenna, having an RF signal input, an AISG signal input, including a DC current, wherein the RF signal input is coupled to the antenna by a filter, so the filter blocks a signal with DC current, and the AISG signal is coupled to the antenna through a switch, so that if an AISG signal is present, the switch automatically allows the AISG signal through to the antenna for control of the antenna, and if no AISG signal is present, the RF signal is automatically allowed through to the antenna for control of the antenna.

The invention relates to the technical field of wireless communication. The invention relates to a driver, in particular to a driver for single-ended driving of an MZM modulator. The driver includes atriode Q1, a resistor R1, a resistor R2, a resistor R3, a high-speed capacitor C1, a current source Is, a power supply Vcc1 and a power supply Vcc2, a first bonding pad is welded to the anode of a first arm optical phase shifter of the MZM modulator, a second bonding pad is welded to the anode of a second arm optical phase shifter of the MZM modulator, the first bonding pad is connected with thepower supply Vcc2 through a load R2, and the second bonding pad is connected with the power supply Vccc2 through the load R3. A radio frequency electric signal to be modulated is input into the base electrode of the triode Q1, the collector electrode of the triode Q1 is connected with the second end of the resistor R1 and the first end of the high-speed capacitor C1, the emitter electrode of the triode Q1 is grounded through the current source Is, and the second end of the capacitor C1 is connected with the first bonding pad. The substantive effects of the invention are that the load resistorof the MZM modulator is used as the pull-up resistor of the driver at the same time, and establishment of a bias-tee circuit structure is not needed; And the power consumption can be obviously reduced.