Bidirectional RF circuit and method of use

Abstract

A bidirectional RF circuit, preferably including a plurality of terminals, switches, transistors, couplers, and a feedback network. The circuit may optionally include a drain matching network, an input matching network, and / or one or more tuning inputs. In some variations, the circuit may optionally include one or more impedance networks, such as an impedance network used in place of a feedback network, and in some such variations, the circuit may not include a coupler, a switch, and / or an input matching network. A method for circuit operation, preferably including operating in an amplifier mode, operating in a rectifier mode, and / or transitioning between operating modes.

Description

Technical Field

[0001] (Cross - Reference to Related Applications) This application claims the benefit of U.S. Provisional Application No. 63 / 292,932, filed on December 22, 2021, and U.S. Provisional Application No. 63 / 352,432, filed on June 15, 2022, which are hereby incorporated by reference in their entireties respectively.

[0002] (Statement of Government Support) This invention was made with government support under Contract No. HR0011210126 awarded by the Defense Advanced Research Projects Agency. The government has certain rights in this invention.

[0003] The present invention generally relates to the field of radio frequency (RF) electronics, and more specifically, to novel and useful bidirectional RF circuits and methods of use.

Brief Description of the Drawings

[0004] [Figure 1] FIG. 1 is a schematic diagram of an embodiment of a bidirectional RF circuit. [Figure 2] FIG. 2A is a schematic diagram of an example of a circuit configured in amplifier mode. FIG. 2B is a schematic diagram of an example of a circuit configured in rectifier mode. [Figure 3] FIG. 3 is a plan view of a specific example of a circuit. [Figure 4] FIG. 4 is a schematic diagram of an embodiment of a method of using a bidirectional RF circuit. [Figure 5] FIG. 5A is a schematic diagram of a first modification of a bidirectional RF circuit. FIG. 5B is a schematic diagram of a second modification of a bidirectional RF circuit. FIG. 5C is a schematic diagram of a third modification of a bidirectional RF circuit. FIG. 5D is a schematic diagram of a fourth modification of a bidirectional RF circuit. FIG. 5E is a schematic diagram of a specific example of a fourth modification of a bidirectional RF circuit configured in the first mode. FIG. 5F is a schematic diagram of a specific example of a fourth modification of a bidirectional RF circuit configured in the second mode. [Figure 6]Figure 6A is a schematic diagram of an example of the first part of the method. Figure 6B is a schematic diagram of an example of the second part of the method. [Figure 7] Figure 7 is a schematic diagram of one embodiment of a bidirectional RF circuit. [Modes for carrying out the invention]

[0005] The following description of preferred embodiments of the present invention is not intended to limit the invention to these preferred embodiments, but rather to enable those skilled in the art to realize and use the invention.

[0006] 1. Overview The bidirectional RF circuit 100 preferably includes a plurality of terminals 110, a switch 120, a transistor 130, a coupler 150, and a feedback network 160 (for example, as shown in Figures 1, 2A, 2B, and / or 3). The circuit may optionally include a drain matching network 140, an input matching network 180, and / or one or more tuned inputs 190. In some modifications, the circuit 100 may optionally include one or more impedance networks 170, such as an impedance network used instead of the feedback network 160, and in some such modifications, the circuit 100 may not include the coupler 150, the switch 120, and / or the input matching network 180, as shown as examples in Figures 5A to 5F. However, the circuit may optionally include any other suitable elements.

[0007] The method 200 for circuit operation preferably includes (for example, as shown in Figure 4) a step S210 in which the circuit operates in amplifier mode, a step S220 in which the circuit operates in rectifier mode, and / or a step S230 in which the circuit transitions between operating modes. However, the method may additionally or alternatively include any other suitable elements.

[0008] 2. Bidirectional RF circuit The circuit 100 is preferably operable between an amplifier mode and a rectifier mode (where, for example, the RF power input is rectified), and more preferably, the circuit 100 can be controlled to transition its configuration between the amplifier mode and the rectifier mode. In amplifier mode, the circuit preferably functions as a power amplifier (for example, amplifying the RF input signal and supplying the amplified signal as an RF power output). In rectifier mode, the circuit preferably functions as a synchronous rectifier (for example, rectifying the RF power input and supplying the rectified power as a DC power output). The circuit 100 is preferably able to perform these functions (or a subset thereof, such as amplification only or rectification only) with high efficiency (however, it may have any suitable amplification and / or rectification efficiency).

[0009] The circuit 100 preferably includes a mode control element that can function to configure the circuit for operation between amplifier mode and rectifier mode (e.g., efficient operation, arbitrary operation, etc.) (e.g., the mode control element controls which mode the circuit operates in and / or is configured to operate in). The mode control element is preferably electrically connected between the RF signal input and the other elements of the circuit (e.g., as shown in Figure 7), but may be connected in any other suitable additional or alternative way. In the example, the mode control element may include a switch (e.g., switch 120), an impedance network (e.g., impedance network 170 such as a variable impedance network), a coupler (e.g., a variable coupler electrically connected to the RF signal input), and / or any other suitable element. However, the circuit may, alternatively, not include such a mode control element, or the mode control element may have fixed rather than variable characteristics (e.g., the RF signal input is electrically coupled to the other elements of the circuit by a fixed circuit element rather than a variable, controllable, and / or configurable element).

[0010] In some embodiments, the bidirectional RF circuit 100 defines a main path 101 and a feedback path 102. The main path is preferably used in both amplifier mode and rectifier mode, and the feedback path is used in amplifier mode (as shown, for example, in Figures 2A and 2B), but preferably not used in amplifier mode. However, the circuit may define any other suitable circuit path with any suitable function, either additionally or alternatively.

[0011] 2.1 Terminals Terminal 110 preferably includes an RF signal input 111, a DC power terminal 112, and an RF power terminal 113 (as shown, for example, in Figures 1, 2A, and / or 2B). However, the circuit 100 may additionally or alternatively include any other suitable terminals.

[0012] When the circuit is configured in amplifier mode (for example, as shown in Figure 2A), it is preferable that the RF signal input 111 functions as an input terminal for receiving the RF signal amplified by the circuit. When the circuit is configured in rectifier mode (for example, as shown in Figure 2B), it is preferable that the RF signal input 111 is disconnected from the circuit (and therefore, it is preferable that the RF signal input does not perform a function in rectifier mode).

[0013] If the circuit is configured in amplifier mode (for example, as shown in Figure 2A), it is preferable that the DC power terminal 112 functions to receive DC power. If the circuit is configured in rectifier mode (for example, as shown in Figure 2B), it is preferable that the DC power terminal functions to output DC power from the circuit.

[0014] The circuit is preferably electrically coupled (e.g., connected) to one or more DC power devices (e.g., DC-powered loads and / or DC power supplies) at the DC power terminal. For example, the circuit may be connected to one or more rechargeable batteries (and / or elements configured to be powered by the batteries and / or the circuit) capable of supplying DC power to and / or receiving DC power from the DC power terminal.

[0015] The DC power terminal is preferably electrically connected to the main path of the circuit. More preferably, the DC power terminal is electrically connected to the main path via a low-pass filter (e.g., an inductive element) or a bias tee (e.g., the DC power terminal is located on the DC bias side of the tee). However, the DC power terminal can alternatively be connected to the circuit (e.g., the main path) via a drain bias network and / or any other suitable method.

[0016] If the circuit is configured in amplifier mode (for example, as shown in Figure 2A), the RF power terminal is preferably configured to output an amplified RF signal from the circuit. If the circuit is configured in rectifier mode (for example, as shown in Figure 2B), the RF power terminal is preferably configured to receive the rectified RF power. The circuit is preferably electrically coupled (e.g., connected) to one or more antennas (e.g., a phased antenna array) via the RF power terminal.

[0017] However, the circuit may include any other suitable terminals, either additionally or alternatively.

[0018] 2.2 Switch Switch 120 preferably functions to transition the system between an amplifier mode and a rectifier mode. Switch 120 is preferably a single-pole double-throw (SPDT) switch. The switch is preferably operable to connect either the RF signal input 111, or the output of the feedback network 160, to the circuit (e.g., to the gate of transistor 130), as illustrated by way of example in FIGS. 2A and 2B.

[0019] In a first switch position where the RF signal input 111 (e.g., as shown in FIG. 2A) is connected to the circuit, the circuit is configured in an amplifier mode and is operable to amplify the RF input signal. In this configuration, the feedback path 102 is preferably disconnected and the feedback network 160 is not used.

[0020] In a second switch position where the feedback network 160 (e.g., as shown in FIG. 2B) is connected to the circuit, the circuit is configured in a rectifier mode and is operable to rectify the RF power input. In this configuration, the RF signal input 111 is disconnected and not used.

[0021] In some variations, the switch can alternatively be a single-pole single-throw (SPST) switch. For example, in variations where the circuit does not include the feedback network 160, such as where an impedance network 170 is used instead of the feedback network, the system optionally includes an SPST switch (e.g., as shown in FIGS. 5D - 5F) that functions to connect the RF signal input to the circuit (at the position where the switch is closed, as shown by way of example in FIG. 5E) and disconnect the RF signal input from the circuit (at the position where the switch is open, as shown in FIG. 5F).

[0022] In some variations, the circuit may additionally or alternatively include one or more non-switching elements configured to provide the switching functions described herein (e.g., to configure or assist in configuring the system between rectifier mode and amplifier mode). For example, the system may include a tunable transmission line (e.g., integrated into an input matching network) that can function to tune (or assist in tuning) gate matching for operation in rectifier mode and amplifier mode (e.g., the tuning of the tunable transmission line may be changed between rectifier mode operation and amplifier mode operation, thereby functioning to tune gate matching for operation in a desired mode, such as optimizing gate matching for operation in a desired mode). In a particular example, transmission line tuning may be changed by controlling one or more variable components (e.g., voltage-controlled centralized components) located on and / or electrically coupled to the transmission line. However, transmission line tuning may additionally or alternatively be controlled in any other suitable way, and / or the system may additionally or alternatively include any other suitable non-switching elements configured to provide this function (or may not include such elements).

[0023] However, the circuit may additionally or alternatively include any other suitable switch and / or be made operable in any other suitable way to transition between amplifier mode and rectifier mode (and / or any other suitable operating mode) (for example, the circuit may not include switch 120, as shown in example in Figure 5B).

[0024] 2.3 Transistors When the circuit is configured in amplifier mode, the transistor preferably functions to modulate the DC power input based on the RF signal input. When the circuit is configured in rectifier mode, the transistor preferably functions to modulate the RF power input based on feedback control (e.g., received from a feedback network).

[0025] The transistor is preferably a field-effect transistor (FET), such as a MOSFET (however, it may be a junction-gate FET (JFET) or other suitable FET instead). However, the transistor may additionally or alternatively be any other transistor type (e.g., an insulated-gate bipolar transistor (IGBT), a bipolar junction transistor (BJT), etc.), and / or the circuit may include any other suitable elements configured to provide multiple transistors (of any suitable type) and / or similar functions. Those skilled in the art will recognize that, in embodiments where the transistor is an FET, the terminals of the transistor are referred to herein as “gate,” “source,” and “drain,” but the terminals of different types of transistors may be referred to by different names, and in the example, such terminals may similarly be the “gate,” “emitter,” and “collector” of an IGBT, or the “base,” “emitter,” and “collector” of a BJT, respectively. In some cases, referring to each of these terminals with general terminology that can be applied regardless of the transistor type can aid understanding. For example, the "gate" of an FET or IGBT and the "base" of a BJT can be called the "switching terminal," while the other terminals can be called the "switch terminals."

[0026] The gate of the transistor is preferably electrically connected to a switch (for example, via an input matching network, optionally). The source of the transistor is preferably connected to ground. The drain of the transistor is preferably connected to the main path 101, and more preferably connected between the drain matching network and the DC power supply terminal. For example, the circuit may include a bias tee connecting the drain, the drain matching network, and the DC power supply terminal (where the DC power supply terminal is on the DC bias side of the bias tee). Furthermore, those skilled in the art will recognize that a similar circuit can be constructed with the terminals of the transistor reversed such that the drain is connected to ground and the source is connected to the main path (where the “drain matching network” may be more appropriately called the “source matching network”).

[0027] However, the circuit may additionally or alternatively include any other suitable transistor in any suitable configuration.

[0028] 2.4 Drain-matched network The circuit may optionally include a drain matching network 140 (drain matcher) that can function to perform impedance matching at the transistor drain (for example, to enable high-efficiency amplification and / or rectification). The drain matching network is preferably electrically coupled to the drain. (As stated above, those skilled in the art will recognize that the circuit may additionally or alternatively include a similar source matching network connected in a similar manner to the transistor source.)

[0029] Drain-matched networks are preferably harmonically terminated. For example, a drain-matched network can define a harmonic-terminating class F-1 topology. However, a drain-matched network can define any other suitable matching topology, either additionally or alternatively.

[0030] Furthermore, the circuit may, in addition or alternatively, include any other drain-matched network, and / or may not include such a network.

[0031] 2.5 Combiner When the circuit is configured in rectifier mode, the coupler 150 preferably functions to split the RF power input between the main path 101 and the feedback path 102. Preferably, the coupler couples the majority of the RF power input to the main path while coupling only a small portion of the RF power input (e.g., -10 to -30 dB) to the feedback path. However, the coupler may, additionally or alternatively, exhibit any other suitable coupling ratio (e.g., substantially equal coupling, such as a -3 dB coupler).

[0032] The coupling ratio can be fixed or variable. In examples where the coupling ratio is variable, the ratio can be tuned as described below with respect to Method 200 (for example, with respect to tuning of rectifier operation such that the coupling ratio is treated as a tuning parameter for optimization), and additionally or alternatively, if the circuit is configured in amplifier mode, the coupling ratio can be optionally tuned to minimize signal coupling to the feedback path (for example, by setting it to zero, minimizing it, etc.).

[0033] The coupler 150 preferably exhibits minimal coupling from the main path to the feedback path (e.g., no coupling or substantially no coupling). Therefore, when the circuit is configured in amplifier mode, it is preferable that the amplified RF signal output at the drain of the transistor (e.g., via a drain-matching network) is transmitted to the RF power supply terminal with minimal coupling to the feedback path (e.g., without coupling or substantially without coupling). However, the coupler may instead exhibit any suitable signal coupling from the main path to the feedback path. For example, a signal coupled to the feedback path while the circuit is configured in amplifier mode may cause signal reflection at a disconnected switch terminal, but a signal coupled to the feedback path while operating in amplifier mode may, additionally or alternatively, yield any other suitable results and / or be processed in any other suitable way.

[0034] However, the circuit may additionally or alternatively include any other suitable coupler having any suitable characteristics. Alternatively, the circuit may not include the coupler 150, as shown as an example in Figures 5A, 5B, and / or 5D (for example, in a variation where the circuit does not include the feedback network 160, for example, if an impedance network 170 is used instead of the feedback network).

[0035] 2.6 Feedback Network When the circuit is configured in rectifier mode, the feedback network 160 preferably functions to enable tuning (e.g., optimization) of the rectification efficiency. The feedback network preferably includes a feedback tuner 161 and may optionally include a driver amplifier 162.

[0036] The feedback tuner 161 preferably functions to control the phase and / or amplitude of the feedback signal. The feedback tuner preferably includes a phase shifter that enables optimization of rectification efficiency. The phase shifter is preferably a variable phase shifter and more preferably allows phase shift control over the entire range of 2π radians (or over any suitable range). However, the phase shifter may alternatively have any other suitable characteristics.

[0037] The feedback tuner preferably includes a variable gain amplifier (VGA), which can enable further optimization of the rectification efficiency by providing control over additional parameters for optimization (for example, with respect to "tuning the rectifier operation," as described below with respect to Method 200). The VGA may additionally or alternatively function to compensate for losses such as losses associated with the phase shifter.

[0038] The VGA is preferably located after the phase shifter along the feedback path (e.g., connected to the phase shifter's output), but it may also be located before the phase shifter or have any other suitable placement.

[0039] Alternatively, a feedback tuner may include a variable attenuator that can function to allow control over the overall gain of the feedback network (for example, by controllably attenuating the feedback signal rather than amplifying it, such as after or before a fixed amplification stage) as an additional or alternative (e.g., instead of or in addition to a VGA).

[0040] The feedback network may optionally include a driver amplifier 162 that can function to provide additional gain (e.g., a fixed amount of gain). The driver amplifier 162 is preferably placed after the feedback tuner 161 along the feedback path (e.g., connected to the output of the feedback tuner), but could instead be placed before the feedback tuner or between the elements of the feedback tuner (e.g., between the phase shifter and the VGA).

[0041] In alternative embodiments, the feedback tuner can provide all or substantially all of the desired gain within the feedback network (for example, if the feedback network does not include a driver amplifier). However, such embodiments may require the use of a high-power VGA, which could reduce the overall power efficiency of the rectifier and / or increase the heat dissipation requirements (for example, because the power requirements of a high-power VGA are increased compared to an equivalent low-power VGA followed by a fixed driver amplifier).

[0042] However, the feedback network 160 may additionally or alternatively include any other suitable elements in any suitable arrangement. Alternatively, the circuit may not include the feedback network 160 at all, as shown as an example in Figures 5A to 5D (for example, in a variation where an impedance network 170 is used instead of the feedback network 160).

[0043] 2.7 Impedance Network In some variations, the circuit may include one or more impedance networks 170 that can function as synchronous drivers for transistor 130 (for example, in rectifier mode). Furthermore, in some examples, the impedance network 170 may optionally function to perform input matching in amplifier mode (for example, instead of input matching network 180).

[0044] In modifications where the circuit includes an impedance network 170 instead of a feedback network (for example, as shown in Figures 5A to 5D), when operating in rectifier mode, a (preferably small) portion of the RF input may leak through the transistor 130 and out of the transistor's gate (or similarly, its base). In such modifications, this leakage current can reach the impedance network 170, be reflected back to the transistor's gate, and there function to control the transistor's operation. Therefore, it is preferable that the impedance network exhibits an appropriate impedance so that this reflected leakage current drives the transistor in a way that results in efficient rectification of the RF input (for example, turning the transistor off when the RF input is high and turning it on when the RF input is low).

[0045] In some examples, an impedance network exhibits a fixed (or substantially fixed) impedance (i.e., an impedance network is a fixed impedance network). For example, an impedance network may include fixed-value electrical elements (e.g., resistive, inductive, and / or capacitive elements, as would define a fixed RLC network).

[0046] In other examples, an impedance network can present a variable (e.g., controllable) impedance (i.e., the impedance network is a variable impedance network that can be switchable, tuned, and / or otherwise controllable). In the first particular example, the impedance network includes one or more tuneable elements (e.g., tuneable resistive, inductive, and / or capacitive elements in addition to fixed-value elements that define a variable RLC network). In the second particular example, the impedance network includes a (switchable) bank of impedance networks having different characteristics (e.g., exhibiting different impedances) (preferably fixed impedance networks, but additionally or alternatively, tuned impedance networks and / or any other suitable networks), the bank can be controlled to exhibit one or more different impedance networks contained therein. Thus, the second example of an impedance network can function to control the impedance it exhibits (e.g., to optimize circuit operation under various conditions).

[0047] In the first modification, the impedance network is positioned opposite the RF signal input 111 with a switch 120 in between, as shown in example Figure 5A (for example, the switch can operate to electrically connect either the RF signal input 111 or the impedance network 170 to a circuit such as the gate of transistor 130). In this modification, the impedance network can be a fixed impedance network or a variable impedance network. In an alternative example of this first modification, the switch is replaced with a coupler, as shown in example Figure 5C (for example, the coupler electrically couples both the RF signal input 111 and the impedance network 170 to a circuit such as the gate of transistor 130), and in this modification of the example, the coupler can be a fixed coupler, a variable coupler, or any other suitable coupler.

[0048] In a second modification, the impedance network may be located within the circuit between the RF signal input and the gate of transistor 130 (e.g., instead of switch 120 and / or input matching network 180), as shown as an example in Figure 5B. In this modification, the impedance network is preferably a variable impedance network (e.g., tunable, switchable, and / or otherwise controllable). When the circuit operates in rectifier mode, the impedance network is preferably controlled to function as a synchronous driver (e.g., as described above). When the circuit operates in amplifier mode, the impedance network is preferably controlled to function as an input matcher (e.g., similar to input matching network 180 described below). However, the impedance network may be additionally or alternatively controlled in any other suitable way, or in alternative embodiments, it may be a fixed impedance network and / or any other suitable network. In an alternative example of this second modification, the circuit includes a switch (e.g., an SPST switch) located between the RF signal input and the impedance network (e.g., as shown in Figures 5D to 5F). Preferably, this switch functions to control whether the RF signal input is electrically coupled to an impedance network (for example, as shown in Figure 5E, the switch can be closed in rectifier mode to couple the RF signal input to an impedance network, and as shown in Figure 5F, the switch can be opened in amplifier mode to prevent the RF signal input from being coupled to an impedance network).

[0049] However, the circuit may, additionally or alternatively, include any other suitable impedance network in any suitable arrangement (or may not include such a network).

[0050] 2.8 Input Matching Network This circuit may optionally include an input matching network 180 that can function to enable high small-signal gain at the gate of the transistor. The input matching network is preferably electrically coupled to the gate, such as being coupled between the switch 120 and the gate.

[0051] The input matching network 180 can have any suitable topology for providing RF impedance matching to the gate. The input matching network is preferably a tunable input matcher, but can have any other suitable additional or alternative characteristics. In one example, the input matching network may have a Class F -1 It includes harmonic termination.

[0052] However, the circuit may, in addition or alternatively, include any other suitable input matching network 180, and / or may not include such a network.

[0053] 2.9 Synchronized Input The circuit may optionally include a tuned input that can function to optimize circuit efficiency in rectifier mode and / or amplifier mode. The tuned input allows for gate bias V gg It is preferable that a DC or substantially constant gate bias can be applied (preferably, but alternatively, any other suitable bias).

[0054] The tuning input is preferably electrically connected to the gate of the transistor, and more preferably connected via a low-pass filter or bias tee. For example, the circuit may include a bias tee connecting the tuning input (the DC bias side of the bias tee) between the gate and the switch (e.g., in embodiments where the circuit includes an input matching network, "between the gate and the input matching network"). However, the tuning input may also be connected to the gate of the transistor via a gate bias network and / or by any other suitable method.

[0055] Furthermore, the circuit may additionally or alternatively include any other suitable tuning input electrically connected to any suitable element of the circuit.

[0056] 2.10 Integration In some embodiments, the circuit 100 may include and / or be coupled thereto (e.g., electrically coupled) to one or more elements, such as those described in U.S. Patent Application No. 17 / 528,869, filed November 17, 2021, entitled “SYSTEM AND METHOD FOR WIRELESS POWER RECEPTION,” and / or U.S. Patent Application No. 17 / 500,652, filed October 13, 2021, each of which is incorporated herein by this reference in whole, for example, the circuit 100 may function as an element of the transmitter and / or receiver (e.g., a node configured to operate as both a transmitter and a receiver) of U.S. Patent Application No. 17 / 528,869 and / or U.S. Patent Application No. 17 / 500,652.

[0057] In one embodiment, the circuit 100 is coupled (e.g., integrated) to a node of a wireless power mesh network that can operate to switch between transmit and receive modes. The node preferably includes one or more antennas (e.g., a phased antenna array) electrically coupled (e.g., connected) to an RF power terminal, one or more DC power devices (e.g., DC powered loads and / or DC power supplies, as described above with respect to DC power terminal 112) electrically coupled (e.g., connected) to a DC power terminal, and a controller configured to control the operation of the circuit 100. In an example, the controller may be configured to control the circuit operating mode (e.g., by controlling switch positions), control some or all of the tuning inputs and / or variable circuit components, supply RF signal inputs, and / or control the circuit operation in any other suitable way. In this embodiment, the circuit 100 can be configured to operate as an amplifier when the node is operating as a transmitter (e.g., amplifying RF signals transmitted by the node), and can be configured to operate as a rectifier when the node is operating as a receiver (e.g., rectifying RF power received by the node).

[0058] However, the circuit 100 can additionally or alternatively include any other suitable elements in any suitable arrangement, have any other suitable functions, and / or integrate with any other suitable system(s) in any suitable manner.

[0059] 3. Method Method 200 is preferably carried out using the bidirectional RF circuit 100 described above. However, this method can be carried out additionally or alternatively using any other suitable system.

[0060] 3.1 Operation in Amplifier Mode Step S210, which operates in amplifier mode, preferably includes receiving DC power (e.g., at the DC power terminal), receiving the RF input signal (e.g., at the RF signal input), amplifying the RF input signal (e.g., using the circuit 100 configured in amplifier mode), and supplying the amplified RF output (e.g., at the RF power terminal), as shown as an example in Figure 6A. Optionally, S210 may include tuning the amplifier operation.

[0061] Tuning the amplifier operation can be achieved by tuning the gate bias, tuning one or more matching networks (e.g., an input matching network, a drain matching network, etc.), and / or tuning any other suitable variable elements of the circuit. Tuning the amplifier operation preferably involves optimizing the amplifier efficiency (e.g., measuring the output and / or input power and maximizing their ratio, e.g., maximizing the output power for a given input power). The amplifier operation can be tuned periodically, in response to the detection of substantial changes in one or more input metrics (e.g., a substantial increase or decrease in the DC power input drain bias, a substantial change in the RF input signal characteristics, etc.), and / or at any other suitable timing.

[0062] However, the S210 may, additionally or alternatively, include operating in amplifier mode in other suitable ways.

[0063] 3.2 Operation in Rectifier Mode Step S220, operating in rectifier mode, preferably includes receiving RF power (e.g., at an RF power terminal), rectifying the RF power, and supplying the rectified power as a DC power output (e.g., at a DC power terminal), as shown as an example in Figure 6B. Optionally, S220 may include synchronizing the rectifier operation.

[0064] Tuning the rectifier operation can be achieved by tuning the gate bias, tuning the feedback network (e.g., tuning the phase shifter and / or VGA), tuning one or more matching networks (e.g., input matching network, drain matching network, etc.), and / or tuning any other suitable variable elements of the circuit. Tuning the rectifier operation preferably involves optimizing the rectifier efficiency (e.g., measuring the output and / or input power and maximizing their ratio, e.g., maximizing the output power for a given input power).

[0065] For example, tuning the operation of a rectifier involves optimizing the gate bias (e.g., by performing a line search), then optimizing the feedback network parameters (e.g., by performing an optimal search across a two-dimensional parameter space defined by the feedback tuner phase shifter and VGA), and optionally, then re-optimizing the gate bias (e.g., by performing a new line search) under the optimized feedback network conditions. In variations, this iterative optimization approach can be repeated any appropriate number of times. However, the tuning parameters can be optimized additionally or alternatively in any other appropriate way.

[0066] The operation of the rectifier can be tuned periodically, in response to the detection of a substantial change in one or more input metrics (e.g., a substantial increase or decrease in RF input power), and / or at any other appropriate timing.

[0067] However, the S220 may, additionally or alternatively, include operating in rectifier mode in other suitable ways.

[0068] 3.3 Transitions between operating modes Step S230, which transitions between operating modes, preferably includes changing the switch configuration. S230 may include transitioning to amplifier mode by configuring the switch to connect an RF signal input to the circuit, or transitioning to rectifier mode by configuring the switch to connect a feedback path to the circuit.

[0069] In some variations (for example, variations in which a controllable impedance network is placed in the circuit between the RF signal input and the gate of a transistor, such as being placed in place of a switch and / or input matching network), S230 may additionally or alternatively include controlling the impedance network based on a desired operating mode (for example, as described above with respect to impedance network 170). S230 may include transitioning to amplifier mode by configuring the impedance network to function as input matching, or transitioning to rectifier mode by configuring the impedance network to function as a synchronous drive (for example, instead of configuring the switch as described above, or in addition to configuring the switch as described above).

[0070] Additionally or alternatively, S230 may, based on the desired operating mode, input one or more tuning elements (e.g., gate bias V such as DC gate bias). gg This may include controlling an element configured to apply a bias to the gate of a transistor. For example, S230 may include switching to a first gate bias (or a bias within a first range of gate biases) as part of a transition to amplifier mode, or switching to a second gate bias (or a bias within a second range of gate biases) as part of a transition to rectifier mode.

[0071] However, S230 may additionally or alternatively include transitions between operating modes in any other suitable manner, and / or method 200 may additionally or alternatively include any other suitable elements performed in any suitable manner.

[0072] The diagrams illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products in preferred embodiments, exemplary configurations, and variations thereof. In this regard, each block in a flowchart or block diagram may represent a module, segment, step, or portion of code containing one or more executable instructions for implementing a specified logical function(s). It should also be noted that in some alternative implementations, the functions shown within a block may occur out of the order shown in the diagram. For example, two consecutively shown blocks may actually be executed substantially simultaneously, or, depending on the functions involved, the blocks may sometimes be executed in reverse order. It should also be noted that each block in a block diagram and / or flowchart, and any combination of blocks in a block diagram and / or flowchart, can be implemented by a special-purpose hardware-based system or a combination of special-purpose hardware and computer instructions that performs a specified function or operation.

[0073] Those skilled in the art can modify and change preferred embodiments of the present invention without departing from the scope of the present invention as defined in the following claims, as can be seen from the above detailed description, drawings and claims.

Claims

1. A bidirectional circuit system, A transistor having a switching terminal, a first switch terminal, and a second switch terminal, An RF power supply terminal electrically coupled to the first switch terminal, A DC terminal electrically coupled to the RF power supply terminal and the first switch terminal via a low-pass filter, RF signal input terminal and A mode control element comprising a first terminal, a second terminal, and a switch, wherein the first terminal is electrically coupled to the switching terminal, and the second terminal is electrically coupled to the RF signal input terminal, A directional coupler electrically coupled between the RF power terminal and the first switch terminal, An input port electrically connected to the RF power terminal, A transmitting port electrically coupled to the first switch terminal, A directional coupler having coupling ports, The system comprises a feedback network that electrically connects the coupling port to the third terminal of the switch, The aforementioned switch is The switch has a first configuration in which the first terminal is electrically connected to the second terminal, The switch is operable between a second configuration in which the first terminal is electrically connected to the third terminal and the first terminal is not electrically connected to the second terminal. The aforementioned system, The switch is an amplifier mode in the first configuration, wherein the circuit is configured to receive an RF input signal at the RF signal input terminal, receive a DC power input at the DC terminal, generate an amplified signal based on the RF input signal using the transistor, and supply the amplified signal at the RF power terminal, A bidirectional circuit system in which the switch is operable between a rectifier mode in the second configuration, wherein the circuit is configured to receive an RF power input at the RF power terminal, rectify the RF power input using the transistor to generate a DC power output, and supply the DC power output at the DC terminal.

2. The system according to claim 1, wherein the feedback network comprises a feedback tuner equipped with a variable phase shifter.

3. The system according to claim 2, wherein the feedback tuner further comprises a variable gain amplifier.

4. The system according to claim 3, wherein the feedback network further comprises a power amplifier electrically coupled between the feedback tuner and the third terminal.

5. The system according to claim 3, wherein in the rectifier mode, the system is operable to synchronize the operation of the feedback tuner in order to optimize the rectification efficiency of the system.

6. The system according to claim 5, further comprising a tuned input electrically coupled to the switching terminal via a second low-pass filter, wherein the tuned input is configured to supply a bias voltage to the switching terminal, and in the rectifier mode, the system is operable to tune the operation of the tuned input in order to optimize the rectification efficiency of the system.

7. The system according to claim 1, wherein the feedback network comprises a feedback tuner equipped with a variable gain amplifier.

8. A drain matching network is electrically coupled between the transmit port and the first switch terminal and is operable to perform impedance matching. An input matching network is electrically coupled between the first terminal and the switching terminal and is operable to perform impedance matching. A tuning input is electrically coupled to the switching terminal via a second low-pass filter and configured to supply a bias voltage to the switching terminal. The system according to claim 1, further comprising:

9. The system according to claim 1, further comprising an impedance network electrically coupled to a third terminal of the switch, wherein in the second configuration, the switch electrically connects the first terminal to the third terminal.

10. The system according to claim 9, wherein the impedance network exhibits substantially fixed impedance.

11. The system according to claim 9, further comprising an input matching network electrically coupled between the first terminal and the switching terminal and operable to perform impedance matching.

12. The system according to claim 1, further comprising an impedance network, wherein the mode control element comprises a first terminal, a second terminal, and a directional coupler that electrically couples the impedance network.

13. The system according to claim 12, wherein the impedance network exhibits substantially fixed impedance.

14. The system according to claim 12, wherein the directional coupler is operable to change the coupling ratio between the first terminal and the second terminal.

15. A drain matching network is electrically coupled between the transmit port and the first switch terminal and is operable to perform impedance matching. An input matching network is electrically coupled between the first terminal and the switching terminal and is operable to perform impedance matching. A tuning input is electrically coupled to the switching terminal via a second low-pass filter and configured to supply a bias voltage to the switching terminal. The system according to claim 1, further comprising:

16. In the system according to any one of claims 1 to 15, A step of operating the system in the amplifier mode, The steps include receiving the RF input signal at the RF signal input terminal, The steps include receiving the DC power input at the DC terminal, A step of generating the amplified signal based on the RF input signal, The steps include supplying the amplified signal at the RF power terminal and Steps including, A step of operating the system in the rectifier mode, The steps include receiving the RF power input at the RF power terminal, The steps include: rectifying the RF power input to generate a DC power output; The steps include supplying the DC power output at the DC terminal and Steps including and A method for bidirectional circuit operation, including the operation of a bidirectional circuit.

17. It is a bidirectional circuit, A transistor having a switching terminal, a first switch terminal, and a second switch terminal, An RF power supply terminal electrically coupled to the first switch terminal, A DC terminal electrically coupled to the RF power supply terminal and the first switch terminal via a low-pass filter, RF signal input terminal and A mode control element comprising a first terminal, a second terminal, and a switch, wherein the first terminal is electrically coupled to the switching terminal, and the second terminal is electrically coupled to the RF signal input terminal, An input matching device that electrically couples the switch to the switching terminal of the transistor, Directional coupler, In a bidirectional circuit comprising a feedback network, During the amplification period, The switch comprises the steps of electrically coupling the RF signal input terminal to the input matching unit, The steps include receiving an RF input signal at the RF signal input terminal, The steps include receiving a DC power input at the aforementioned DC terminal, The steps include: generating an amplified signal based on the RF input signal using the transistor; The steps include supplying the amplified signal at the RF power terminal, During the rectification period, The switch comprises the steps of electrically coupling the feedback network to the input matching unit, The steps include receiving RF power input at the RF power terminal, The steps include: using the transistor to rectify the RF power input and generate a DC power output; The steps include supplying the DC power output at the DC terminal, Includes, The amplification period does not overlap with the rectification period. During the rectification period, the switch does not electrically couple the RF signal input terminal to the input matching unit. The directional coupler is electrically coupled between the RF power terminal, the first switch terminal of the transistor, and the feedback network. The feedback network is a method of electrically coupling the directional coupler to the switch.

18. The method according to claim 17, wherein the amplification period precedes the rectification period, and the method further includes a step of switching the bidirectional circuit operation from amplification mode to rectification mode between the amplification period and the rectification period.

19. After the rectification period, the bidirectional circuit operation is switched from the rectification mode to the amplification mode, After switching the bidirectional circuit operation from the rectification mode to the amplification mode, in the bidirectional circuit, The steps include receiving a second RF input signal at the RF signal input terminal, The steps include receiving a second DC power input at the DC terminal, The steps include generating a second amplified signal based on the second RF input signal, The steps include supplying the second amplified signal to the RF power supply terminal and The method according to claim 18, further comprising:

20. The bidirectional circuit further comprises a directional coupler, an impedance network, an input matching circuit, and a transistor. The input matching device electrically connects the directional coupler to the switching terminal of the transistor. The method according to claim 17, further comprising the step of electrically coupling the RF signal input terminal, the impedance network, and the input matching unit in the directional coupler during the amplification period and the rectification period.

21. The method according to claim 20, wherein the impedance network exhibits substantially fixed impedance throughout the amplification period and the rectification period.

22. The amplification period precedes the rectification period, The directional coupler defines the coupling ratio between the RF signal input terminal and the input matching unit. The method according to claim 20, further comprising the step of switching the bidirectional circuit operation from amplification mode to rectification mode by configuring the directional coupler to change the coupling ratio between the amplification period and the rectification period.

23. During the amplification period, the coupling ratio has a first value, The method according to claim 22, wherein during the rectification period, the coupling ratio has a second value substantially smaller than the first value.

24. During the aforementioned rectification period, The directional coupler comprises the step of coupling a portion of the RF power input to the feedback network, The feedback network includes the step of modifying the portion of the RF power input by performing at least one of phase shifting, amplification, or attenuation. The steps include supplying the modified portion of the RF power input to the input matching unit. The method according to claim 17, further comprising:

25. The aforementioned feedback network includes a feedback tuner equipped with a variable phase shifter, The method according to claim 24, wherein the step of changing the portion of the RF power input includes the step of shifting the phase of the portion of the RF power input.

26. The aforementioned feedback tuner further comprises a variable gain amplifier, The method according to claim 25, wherein the step of modifying the portion of the RF power input further includes the step of amplifying the portion of the RF power input.

27. The method according to claim 26, wherein the feedback network further comprises a power amplifier electrically coupled between the feedback tuner and the switch.

28. The amplification period precedes the rectification period, The method according to any one of claims 17 to 24, further comprising the step of switching the bidirectional circuit operation from amplification mode to rectification mode between the amplification period and the rectification period by configuring the switch to electrically couple the feedback network to the input matcher and to not electrically couple the RF signal input terminal to the input matcher.

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