A technique for attenuating common mode transient events uses a differential receiver circuit including a band-stop filter having a stopband f.sub.SB around a notch frequency f.sub.n of a received signal. The differential receiver circuit includes a first high-pass filter coupled in series with the band-stop filter. The notch frequency f.sub.n is less than a carrier frequency f.sub.c of a signal received by the differential receiver circuit. The band-stop filter may include a buffer circuit and a notch filter coupled in series with the buffer circuit. The notch filter may have a second stopband around the notch frequency f.sub.n. The differential receiver circuit may have a propagation delay that is independent of a pulse width of common mode transient energy attenuated by the differential receiver circuit.

A spatial power-combining device and an antenna structure designed for high efficiency, high frequency, and ultra-wide bandwidth operation. The antenna structure may include a signal conductor and a ground conductor that are entirely separated by air. A spatial power-combining device may include a plurality of amplifier assemblies including multiple output antenna structures and an output coaxial waveguide section configured to concurrently combine signals received from each output antenna structure of the plurality of amplifier assemblies. The plurality of amplifier assemblies may also include multiple input antenna structures and an input coaxial waveguide configured to provide an input signal concurrently to each input antenna structure of the plurality of amplifier assemblies.

Spatial power-combining devices and, in particular, spatial power-combining devices with filtering elements are disclosed. A spatial power-combining device includes a plurality of amplifier assemblies and each amplifier assembly includes an input antenna structure, an amplifier, an output antenna structure, and a filtering element. A filtering element may be an integral single component with an input signal conductor of the input antenna structure or an integral single component with an output signal conductor of the output antenna structure. In some aspects, a filtering element may be an integral single component with both the input signal conductor and the output signal conductor.

Spatial power-combining devices with increased output power are disclosed. A spatial power-combining device includes a plurality of amplifier assemblies and each of the amplifier assemblies includes a plurality of amplifiers separately coupled to a plurality of antennas. An amplifier assembly includes a first amplifier sub-assembly and a second amplifier sub-assembly. The first amplifier sub-assembly includes a first amplifier, a first input antenna structure coupled to the first amplifier, and a first output antenna structure coupled to the first amplifier. The second amplifier sub-assembly includes a second amplifier, a second input antenna structure coupled to the second amplifier, and a second output antenna structure coupled to the second amplifier.

An inductive synthesis circuit that mimics an ideal inductor over a wide range of inductance values, from less than 1 mH to more than 100 H, can be used in place of an inductor in any electrical circuit. One application of a synthesized inductor is in an integrated circuit in which it is impractical to construct a coil of wire. The inductive synthesis circuit is suitable for use in a calibration instrument for testing an inductance meter. The inductive synthesis circuit, together with a resistive synthesis circuit and a capacitive synthesis circuit, can be used to calibrate a multi-meter. Alternatively, the inductive synthesis circuit can be used to mimic an ideal inductor in a filter circuit that includes an inductor component, such as a high pass filter, a notch filter, or a band pass filter.

A gate drive circuit arranged to receive an input signal and provide an output signal to drive a gate of a transistor is presented. The gate drive circuit comprises a filter circuit arranged to attenuate a frequency band from the input signal when deriving the output signal from the input signal. The filter circuit contains programmable resistive elements, comprising: a first programmable resistive element arranged to adjust a low frequency gain and bandwidth of the gate drive circuit; a second programmable resistive element arranged to adjust a high frequency gain of the gate drive circuit; and a pair of programmable resistive elements arranged to adjust a driving gain of the gate drive circuit. A method of receiving an input signal and deriving an output signal from an input signal is also presented. The step of deriving an output signal comprises attenuating a frequency band from the input signal.

In a system comprising a plurality of gain elements configured in parallel to one another, a harmonically tuned filter provides an isolation circuit to prevent odd-mode differential oscillations. A harmonically tuned filter comprises resistors, inductors, and capacitors (RLC) to selectively allow one or more specific harmonics to pass through the isolation circuit to suppress the odd-mode oscillation. Direct current (DC) and other non-harmonically-related frequencies do not pass through the isolation circuit. Since the resistor is used to dissipate specifically the energy of the harmonic frequencies causing the odd-mode oscillation, the current density through the resistor is much lower than the current density of a typical odd-mode resistor without a harmonically tuned filter.

The embodiments of the present disclosure are for a signal processing circuit. The signal processing circuit includes an analog circuit. The analog circuit is used for processing an initial signal it receives. The initial signal includes a target signal and a noise signal. The analog circuit includes a first processing circuit and a second processing circuit. The first processing circuit is used to increase a ratio of the target signal to the noise signal, and output a first processed signal. The second processing circuit is used to amplify the first processed signal. A gain multiple of the second processing circuit to the first processed signal varies with a frequency of the first processed signal. The first processing circuit includes a common mode signal suppression circuit used to suppress a common mode signal in the initial signal, a low-pass filter circuit, and a high-pass filter circuit.

A reconfigurable filter circuit has a first path including a transimpedance amplifier (TIA). The transimpedance amplifier has an input that receives an input current and an output that outputs a voltage. The reconfigurable filter circuit also includes a switchable feedback path. The switchable feedback path includes a first low-pass filter coupled to an output of the TIA. The switchable feedback path also includes a first switch to couple the feedback path to provide a feedback current to the first path resulting in a bandpass response in the output voltage when the switch is closed and a low-pass response in the output voltage when the switch is open.

In one embodiment a tracking circuit for tracking a frequency of a sweeping signal component in an input signal comprises an input (9) for receiving the input signal (Sin) comprising the sweeping signal component and a noise component, a mixer (10) coupled to the input and configured to mix the input signal (Sin) with a replica signal (Srep) and therefrom provide a residual input signal (Sinr), a low-pass filter (20) coupled downstream of the mixer (10), a discriminator circuit (30) coupled downstream of the low-pass filter (20), a loop filter (40) coupled downstream of the discriminator circuit (30) and configured to provide a frequency control value (Sfc), and a replica signal generator circuit (50) coupled downstream of the loop filter (40) and configured to provide the replica signal (Srep) with a frequency adjusted based on the frequency control value (Sfc), wherein the frequency of the replica signal (Srep) represents an estimation of a frequency of the sweeping signal component propagated to a current time unit of the input signal (Sin).