Disclosed herein are printed circuit boards with embedded solenoid filters through which signal traces pass to filter unwanted noise and electromagnetic interference. A printed circuit board comprises a least three layers, a solenoid embedded within the at least three layers, and at least one trace extending through the solenoid. The insertion loss characteristics of the solenoid filter can be tuned by modifying the number of turns in the solenoid(s) and the width of the solenoid(s). The solenoid filter may comprise multiple solenoids connected in series, with adjacent solenoids having opposite wind directions. Surface components may be included on the board to tune the insertion loss further.

Systems and methods for introducing DC bias in a radio frequency (RF) signal communicated over a transmission line are provided. In one example implementation, the RF system can include a transmission line having a first port and a second port. The transmission line can be configured to communicate an RF signal between a first port and a second port. One or more DC bias resistors can be coupled to the transmission line at a location between the first port and the second port. Each DC bias resistor can provide a path for injecting DC current to the transmission line to provide DC bias for the RF signal. Each DC bias resistor can be coupled to the transmission line via a point connection.

Disclosed herein are printed circuit boards with embedded solenoid filters through which signal traces pass to filter unwanted noise and electromagnetic interference. A printed circuit board comprises a least three layers, a solenoid embedded within the at least three layers, and at least one trace extending through the solenoid. The insertion loss characteristics of the solenoid filter can be tuned by modifying the number of turns in the solenoid(s) and the width of the solenoid(s). The solenoid filter may comprise multiple solenoids connected in series, with adjacent solenoids having opposite wind directions. Surface components may be included on the board to tune the insertion loss further.

Aspects of the disclosure are directed to an inductor-capacitor (LC) resonator. In accordance with one aspect, the LC resonator architecture includes a lower metal plate, the lower metal plate is of an open configuration; an upper metal plate, the upper metal plate is stacked vertically above the lower metal plate and is vertically aligned to the lower metal plate; a first ultra thick metal (UTM) plate, the first UTM plate is stacked vertically above the upper metal plate and is vertically aligned to both the upper metal plate and the lower metal plate; and an electrical coupling to couple the first UTM plate to the upper metal plate, wherein a current on the first UTM plate flows through to the upper metal plate through the electrical coupling, the current flows in a direction on the first UTM plate and in the same direction on the upper metal plate.

A circuit for blocking undesired input direct current of AC-coupled broadband circuits. The circuit includes a capacitor coupled to an input port and a common node. The input port receives a RF input signal. Additionally, the circuit includes a current source supplying a DC current to the common node leading a bias current to an output port. Further, the circuit includes a variable voltage source through an internal load and a close loop with an application circuit having an input load coupled to the output port to determine various bias voltages to control the bias current at the output port in association with a RF output signal that is substantially free of any input direct current originated from the RF input signal and is associated with an inherent low cut-off frequency independent of the various bias voltages.

A signal transmission device including a signal wiring, a wide wiring that is formed continuously with one and the other of the signal wirings and has a wiring width larger than a wiring width of at least the one or the other of the signal wirings, a power wiring to which a signal/power separation filter is connected via a branch wiring branching from the wide wiring, and an open stub wiring that is connected to the branch wiring and has an open tip.

An isolator, circuit, and isolation method are disclosed. An illustrative capacitive isolator is disclosed to include an input side that receives an electrical input signal, an output side that outputs an electrical output signal, and an isolation barrier that electrically isolates the input side from the output side. The input side is further disclosed to include an array of input capacitors, where each capacitor in the array of input capacitors receives an input pulse based on the electrical input signal, where each capacitor in the array of input capacitors receives the input pulse offset from input pulses received at others of the capacitors in the array of input capacitors thereby extending a pulse duration of the electrical input signal.

Systems and methods for enhanced high frequency power bias tee designs are provided. In one embodiment, a bias tee network comprises: a first port configured to couple across a data line comprising a first electrically conducting line and a second electrically conducting line; a second port configured to couple to a power port of an electrical device; and a distributed impedance interface coupled between the power supply unit and the differential data line, wherein the distributed impedance interface includes a ferrite impedance gradation network having a plurality of ferrite impedance elements series coupled in an order of progressing impedance, wherein a low impedance end of the first ferrite impedance gradation network is coupled to the first port.

There is provided a converter for converting a received RF signal into a DC signal for powering a load, the converter comprising: a rectifier arranged to generate, based on the RF signal, the DC signal and one or more harmonics of the RF signal, and to output the DC signal and the one or more harmonics together with a component of the RF signal; a first planar transmission line arranged to guide the received RF signal to the rectifier; and a second planar transmission line arranged to receive from the rectifier the DC signal, the component of the RF signal and the one or more harmonics from the rectifier, and to reflect the one or more harmonics back towards the rectifier. The first planar transmission line is further arranged to reflect back towards the rectifier RF signals from the rectifier that are based on the reflected signals. The converter further comprises a low-pass filter for supplying the DC signal to the load, the low-pass filter comprising an inductor and a third planar transmission line that. connects the second transmission line to the inductor, wherein the third planar transmission line and the inductor are arranged to transmit the DC signal and to substantially block the component of the RF signal and the harmonics of the RF signal.

There is provided a dual-band converter operable to convert a first RF signal in a first frequency band and a second RF signal in a second frequency band that is separate from the first frequency band into a DC signal for powering a load. The converter comprises: a rectifier arranged to generate, based on the first and second RF signals, the DC signal and two or more harmonics of each of the first and second RF signals during operation of the dual-band converter; a planar transmission line arranged to guide the first and second RF signals to the rectifier and to receive a component of each of the harmonics generated by the rectifier during operation of the dual-band converter; a first stub and a second stub each connected to the planar transmission line and arranged to reflect, during operation of the dual-band converter, a component of a first harmonic and a component of a second harmonic of the first RF signal received from the rectifier, respectively; and a third stub and a fourth stub each connected to the planar transmission line and arranged to reflect, during operation of the dual-band converter, a component of a first harmonic and a component of a second harmonic of the second RF signal received from the rectifier, respectively.