This application provides a spoof surface plasmon polariton transmission line structure, a circuit board, and an electronic device, to reduce a size of the SSPP transmission line structure. The SSPP transmission line structure includes a first dielectric substrate, a first metal strip, and a second metal strip. The first metal strip and the second metal strip are respectively disposed on two opposite surfaces of the first dielectric substrate, the first metal strip and the second metal strip separately extend in a first direction, and a length of the first metal strip in the first direction is less than a length of the second metal strip in the first direction. In the first direction, a cross-sectional area of the first metal strip gradually decreases, and at least one side of the second metal strip has a plurality of protrusion parts spaced apart.

Disclosed are apparatuses and methods of tuning a radio frequency circuit using stub tuners and photoconductive switches. In one aspect an electromagnetic stub tuner apparatus is disclosed. the apparatus includes a transmission line, and a photoconductive switch positioned along the length of the transmission line. The photoconductive switch is configured to turn on or turn off, wherein an impedance of the transmission line is changed when the photoconductive switch is turned on compared to when the photoconductive switch is turned off. In another aspect, a method of tuning a radio frequency circuit is disclosed. In yet another aspect, a method of producing a radio frequency tuning circuit is disclosed.

This document describes techniques, apparatuses, and systems utilizing a high-isolation transition design for differential signal ports. A differential input transition structure includes a first layer and a second layer made of a conductive metal and a substrate positioned between the first and second layers. The second layer includes a first section that electrically connects to a single-ended signal contact point and to a first contact point of a differential signal port. The first section includes a first stub based on an input impedance of the single-ended signal contact point and a second stub based on a differential input impedance associated with the differential signal port. The second layer includes a second section that electrically connects to a second contact point of the differential signal port and to the first layer through a via housed in a pad. The second section includes a third stub associated with the differential input impedance.

This document describes techniques, apparatuses, and systems utilizing a high-isolation transition design for differential signal ports. A differential input transition structure includes a first layer and a second layer made of a conductive metal and a substrate positioned between the first and second layers. The second layer includes a first section that electrically connects to a single-ended signal contact point and to a first contact point of a differential signal port. The first section includes a first stub based on an input impedance of the single-ended signal contact point and a second stub based on a differential input impedance associated with the differential signal port. The second layer includes a second section that electrically connects to a second contact point of the differential signal port and to the first layer through a via housed in a pad. The second section includes a third stub associated with the differential input impedance.

A new two-probe waveguide slide screw load-pull tuner of which the probes share the same waveguide section; they are inserted diametrically at fixed depth into facing each other slots on opposite broad walls of the waveguide. The tuner does not have cumbersome adjustable vertical axes controlling the penetration of the probes and its low profile is optimized for on-wafer operations. The carriages holding the probes are moved along the waveguide using electric stepper motors or linear actuators.

A new two-probe waveguide slide screw load-pull tuner of which the probes share the same waveguide section; they are inserted diametrically at fixed depth into facing each other slots on opposite broad walls of the waveguide. The tuner does not have cumbersome adjustable vertical axes controlling the penetration of the probes and its low profile is optimized for on-wafer operations. The carriages holding the probes are moved along the waveguide using electric stepper motors or linear actuators.

A method for instantaneous load pull impedance pattern generation uses a phase-frequency-location equivalent of the natural behavior of slide screw tuners to skew the reflection factor phase with only small frequency changes. The method is generic and applies the same to all GHz range test frequencies. A simple calculation determines the tuning probe position and the impedance cloud is generated quasi instantaneously by switching between sidebands of the carrier test frequency without mechanically moving the tuning probe. Benign frequency behavior of the tuners allows for simple and accurate narrowband interpolation. Duration of load pull measurements is reduced from minutes to seconds.

A method for instantaneous load pull impedance pattern generation uses a phase-frequency-location equivalent of the natural behavior of slide screw tuners to skew the reflection factor phase with only small frequency changes. The method is generic and applies the same to all GHz range test frequencies. A simple calculation determines the tuning probe position and the impedance cloud is generated quasi instantaneously by switching between sidebands of the carrier test frequency without mechanically moving the tuning probe. Benign frequency behavior of the tuners allows for simple and accurate narrowband interpolation. Duration of load pull measurements is reduced from minutes to seconds.

A ceramic waveguide filter, a radio unit, an antenna unit and a base station are disclosed. According to an embodiment, a ceramic waveguide filter comprises a body (1) that is made of a ceramic material and that has a plurality of resonators each including a blind hole (101). The blind holes (101) of two of the resonators open at a first surface of the body (1) and extend toward an opposite econd surface of the body (1). Capacitive coupling between the two resonators is achieved by a coupling structure (201) on/in a substrate (2), to which the body (1) is attached at the side of the second surface.

A ceramic waveguide filter, a radio unit, an antenna unit and a base station are disclosed. According to an embodiment, a ceramic waveguide filter comprises a body (1) that is made of a ceramic material and that has a plurality of resonators each including a blind hole (101). The blind holes (101) of two of the resonators open at a first surface of the body (1) and extend toward an opposite econd surface of the body (1). Capacitive coupling between the two resonators is achieved by a coupling structure (201) on/in a substrate (2), to which the body (1) is attached at the side of the second surface.