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.

Isolation characteristics of a directional coupler are improved. A high-frequency module (1) includes a substrate (2) and a directional coupler (5) provided on the substrate (2). The directional coupler (5) includes a main line (51), a sub line (52), and an impedance adjustment portion (7). The sub line (52) is electromagnetically coupled to the main line (51). The impedance adjustment portion (7) is provided in the sub line (52), and adjusts impedance of the directional coupler (5). The impedance adjustment portion (7) is electrically connected to an inductor of the substrate (2).

Isolation characteristics of a directional coupler are improved. A high-frequency module (1) includes a substrate (2) and a directional coupler (5) provided on the substrate (2). The directional coupler (5) includes a main line (51), a sub line (52), and an impedance adjustment portion (7). The sub line (52) is electromagnetically coupled to the main line (51). The impedance adjustment portion (7) is provided in the sub line (52), and adjusts impedance of the directional coupler (5). The impedance adjustment portion (7) is electrically connected to an inductor of the substrate (2).

A number of monolithic multi-throw diode switch structures are described. The monolithic multi-throw diode switches can include a hybrid arrangement of diodes with different intrinsic regions, all formed over the same semiconductor substrate. In one example, two PIN diodes in a monolithic multi-throw diode switch have different intrinsic region thicknesses. The first PIN diode has a thinner intrinsic region, and the second PIN diode has a thicker intrinsic region. This configuration allows for both the thin intrinsic region PIN diode and the thick intrinsic region PIN diode to be individually optimized. As one example, for a switch functioning in a dedicated transmit/receive mode, the first transmit PIN diode can have a thicker intrinsic region than the second receive PIN diode to maximize power handling for the transmit arm and maximize receive sensitivity and insertion loss in the receive arm.

A high-frequency switch circuit includes a first switch configured to electrify or cut off connection between an antenna terminal and an input terminal, and a second switch configured to electrify or cut off connection between the antenna terminal and an output terminal. The first switch has a transmission line connecting the antenna terminal and the input terminal; a diode having an anode connected to a first node between the transmission line and the input terminal, and a cathode connected to a second node; and a capacitor connected to the second node and a first power supply voltage. A first control terminal is connected to the first node via a first resistor and a first inductor. The first switch further includes a charging/discharging circuit connected to a second power supply voltage and the first control terminal and charging and discharging the capacitor from the second node.

A high-frequency switch circuit includes a first switch configured to electrify or cut off connection between an antenna terminal and an input terminal, and a second switch configured to electrify or cut off connection between the antenna terminal and an output terminal. The first switch has a transmission line connecting the antenna terminal and the input terminal; a diode having an anode connected to a first node between the transmission line and the input terminal, and a cathode connected to a second node; and a capacitor connected to the second node and a first power supply voltage. A first control terminal is connected to the first node via a first resistor and a first inductor. The first switch further includes a charging/discharging circuit connected to a second power supply voltage and the first control terminal and charging and discharging the capacitor from the second node.

A directional coupler (1) includes a substrate (10), a main line (20) formed directly or indirectly on the substrate (10), sub-lines (21, 22 and 23) at least part of each of which is formed directly or indirectly on the substrate (10) along the main line (20), a switch (30) switching connections among end portions of the plurality of sub-lines (21, 22 and 23), and detection output terminals (FWD and REV) connected to the sub-line (21), wherein, when looking at the substrate (10) in plan, the end portions of the sub-lines (21, 22 and 23) are disposed on the opposite side to the detection output terminals (FWD and REV) relative to the main line (20), and the sub-line (21) to which the detection output terminals (FWD and REV) are connected is overlapped with or surrounded by the sub-lines (22 and 23).

A directional coupler (1) includes a substrate (10), a main line (20) formed directly or indirectly on the substrate (10), sub-lines (21, 22 and 23) at least part of each of which is formed directly or indirectly on the substrate (10) along the main line (20), a switch (30) switching connections among end portions of the plurality of sub-lines (21, 22 and 23), and detection output terminals (FWD and REV) connected to the sub-line (21), wherein, when looking at the substrate (10) in plan, the end portions of the sub-lines (21, 22 and 23) are disposed on the opposite side to the detection output terminals (FWD and REV) relative to the main line (20), and the sub-line (21) to which the detection output terminals (FWD and REV) are connected is overlapped with or surrounded by the sub-lines (22 and 23).

A dual-band filtering switch based on a single quad-mode dielectric resonator (DR) includes: a first printed circuit board (PCB) provided thereon with an input terminal; a second PCB provided thereon with an output terminal; a shielding shell arranged between the first and second PCBs and enclosing a shielding cavity together with the first and second PCBs; and a single quad-mode DR arranged in the shielding cavity. The first and second PCBs each include a feeding layer, a dielectric layer, and a ground layer that are stacked in sequence. The feeding layers of the first and second PCBs each include a microstrip line and a switching circuitry connected to the microstrip line, and the feeding layer is in contact with a surface of the DR to realize a switching function of the filtering switch. The proposed filtering switch feature low loss transmission and high selectivity with dual-band operation, miniaturization with the fewest resonators and friendly-integration, simultaneously.

A dual-band filtering switch based on a single quad-mode dielectric resonator (DR) includes: a first printed circuit board (PCB) provided thereon with an input terminal; a second PCB provided thereon with an output terminal; a shielding shell arranged between the first and second PCBs and enclosing a shielding cavity together with the first and second PCBs; and a single quad-mode DR arranged in the shielding cavity. The first and second PCBs each include a feeding layer, a dielectric layer, and a ground layer that are stacked in sequence. The feeding layers of the first and second PCBs each include a microstrip line and a switching circuitry connected to the microstrip line, and the feeding layer is in contact with a surface of the DR to realize a switching function of the filtering switch. The proposed filtering switch feature low loss transmission and high selectivity with dual-band operation, miniaturization with the fewest resonators and friendly-integration, simultaneously.