Reconfigurable power amplitude limiter and multistage reconfigurable power amplitude limiter

Abstract

The invention provides a reconfigurable power amplitude limiter and a multi-stage reconfigurable power amplitude limiter, and the reconfigurable power amplitude limiter comprises a power detection unit which is selectively connected with a radio frequency port through a plurality of mutually independent power detection ports so as to detect input power and generate control voltage according to the input power; and the power discharge unit is selectively connected with the radio frequency port through a plurality of mutually independent power discharge ports and limits the amplitude of the output power of the radio frequency port under the action of the control voltage. The power amplitude limiter can be reconstructed by selectively connecting the power detection port and the power discharge port, and different amplitude limiting output requirements are met.

Description

Technical Field

[0001] The present invention relates to a field, and in particular to a reconfigurable power limiter and a multi-stage reconfigurable power limiter. Background Art

[0002] The power limiter is used in RF transceiver systems to limit the input power of the receiving channel to a certain level, protecting the low-noise amplifier and mixer at the subsequent stage from damage due to excessive input power. However, the limiting amplitude of existing power limiters is usually not adjustable, and the application scenarios are limited. Summary of the invention

[0003] In view of the above problems existing in the prior art, the present invention proposes a reconfigurable power limiter and a multi-stage reconfigurable power limiter, which mainly solve the problem that the limiting output power of the existing power limiter cannot be flexibly adjusted.

[0004] In order to achieve the above purpose and other purposes, the technical solution adopted by the present invention is as follows.

[0005] The present application provides a reconfigurable power limiter, comprising: a power detection unit, which is selectively connected to a radio frequency port through a plurality of independent power detection ports to detect input power and generate a control voltage according to the input power; a power discharge unit, which is selectively connected to the radio frequency port through a plurality of independent power discharge ports to limit the output power of the radio frequency port under the action of the control voltage.

[0006] In one embodiment of the present application, the power detection unit includes multiple parallel detection branches, wherein each of the detection branches includes a first resistor and at least one diode connected in series in sequence; the input end of each of the detection branches is the power detection port, which is used to establish a connection with the RF port; the output end of each of the detection branches is grounded through a capacitor, and the output end of the detection branch serves as the output port of the control voltage. When any of the detection branches is in the on state, the control voltage is generated by charging the capacitor.

[0007] In one embodiment of the present application, the power detection unit also includes a discharge circuit, one end of the discharge circuit is connected to the output end of each detection branch, and the other end is grounded. After power is off, the charge in the capacitor is released through the discharge circuit.

[0008] In an embodiment of the present application, the number of diodes connected in series in each of the detection branches is different.

[0009] In one embodiment of the present application, the power discharge unit includes multiple parallel discharge branches, wherein each of the discharge branches includes at least one transistor and a second resistor, the gate of each of the transistors is connected to the input port of the control voltage through a second resistor, and one end of each of the discharge branches is grounded, and the other end serves as a power discharge port.

[0010] In an embodiment of the present application, the numbers of transistors connected in series in each of the discharge branches are different.

[0011] The present application also provides a multi-stage reconfigurable power limiter, comprising: a plurality of the reconfigurable power limiters, wherein the radio frequency ports of the reconfigurable power limiters are cascaded to each other and connected to the radio frequency input and the radio frequency output.

[0012] As described above, the reconfigurable power limiter and the multi-stage reconfigurable power limiter provided by the present application have the following beneficial effects.

[0013] The present application sets a power detection unit and a power discharge unit, and starts the power discharge unit to limit the output power through the input power detected by the power detection unit. The power detection unit and the power discharge unit are both provided with multiple independent interfaces, and the ports can be selected to establish connections as needed, thereby realizing the reconstruction of the power limiter, and then adjusting the limiting amplitude to meet different limiting output requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 Schematic diagram of a reconfigurable power limiter in one embodiment of the present application.

[0015] Figure 2 FIG. 4 is a circuit diagram of a power detection unit in an embodiment of the present application.

[0016] Figure 3 FIG. 4 is a circuit diagram of a power discharge unit in an embodiment of the present application.

[0017] Figure 4 Schematic diagram of a first-level reconfigurable power limiter in one embodiment of the present application.

[0018] Figure 5 Schematic diagram of a multi-stage reconfigurable power limiter in one embodiment of the present application. DETAILED DESCRIPTION

[0019] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0020] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention, and thus the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0021] The inventors have found that:

[0022] The power limiter is used in the RF transceiver system to limit the input power of the receiving channel to a certain amplitude, protecting the low noise amplifier and mixer of the subsequent stage from damage due to excessive input power. The conventional power limiter adopts a PIN diode structure. When the input RF power exceeds the conduction voltage of the PIN diode, the PIN diode is turned on and the RF power is discharged, thereby achieving RF power limiting. The conduction voltage of the PIN diode is determined by the thickness of the I layer and cannot be adjusted at will. Therefore, the limited output power of the power limiter with a PIN diode structure cannot be adjusted in the application.

[0023] Based on the above problems existing in the prior art, the present application proposes a reconfigurable power limiter and a multi-stage reconfigurable power limiter. The technical solution of the present application is described in detail below in conjunction with specific embodiments.

[0024] See also Figure 1 , Figure 1The module diagram of the reconfigurable power limiter in one embodiment of the present application. The reconfigurable power limiter provided in the embodiment of the present application includes: a power detection unit, which is selectively connected to the RF port through a plurality of independent power detection ports to detect the input power and generate a control voltage according to the input power; a power discharge unit, which is selectively connected to the RF port through a plurality of independent power discharge ports, and limits the output power of the RF port under the control voltage. The number of power detection ports in the power detection unit and the number of power discharge ports in the power discharge unit can be set and adjusted according to actual application requirements, and are not limited here. Any power detection port in the power detection unit can be selected to be connected to the RF port, and then the input power of the RF port is received. When the input power exceeds the preset power threshold, the detection branch connected to the power detection port is turned on, and then a control voltage is generated, and the control voltage is input into the power discharge unit. Any power discharge port can be selected to be connected to the RF port as needed, and then the output power of the RF port is limited. The reconstruction of the power limiter is achieved by selecting and connecting different power detection ports and power discharge ports to meet different limited output power requirements.

[0025] In one embodiment, the power detection unit includes multiple parallel detection branches, wherein each of the detection branches includes a first resistor and at least one diode connected in series in sequence; the input end of each of the detection branches is the power detection port, which is used to establish a connection with the radio frequency port; the output end of each of the detection branches is grounded through a capacitor, and the output end of the detection branch serves as the output port of the control voltage. When any of the detection branches is in the on state, the control voltage is generated by charging the capacitor.

[0026] See also Figure 2 , Figure 2 The power detection unit may include N detection branches, each of which is composed of a resistor and a diode in series, and the connection point of each detection branch in parallel is used as a control voltage V ctrl The output terminal of the b Ground.

[0027] In one embodiment, the power detection unit further includes a discharge circuit, one end of which is connected to the output end of each detection branch, and the other end is grounded. After power is turned off, the charge in the capacitor is released through the discharge circuit. The discharge circuit can use a discharge resistor R b When one of the detection branches is turned on, the capacitor C b Charging causes the voltage at the output end of the detection branch to increase, thereby generating a control voltage V ctrlWhen the input power of the detection branch is lower than the detection branch opening power, the discharge resistor R b The capacitor C b The charge in the control voltage V ctrl The potential of the output end becomes 0V. Of course, the discharge circuit can also be composed of other components as long as the capacitor C b The function of releasing the charge in the reactor is sufficient and there is no limitation here.

[0028] In one embodiment, the number of diodes connected in series in different detection branches is different. Taking three detection branches as an example, the power detection port of the first detection branch is connected to one end of the first resistor, the other end of the first resistor is connected to the positive end of the diode, and the negative end of the diode is used as the output end of the detection branch; the power detection port of the second detection branch is connected to one end of the first resistor of the branch, and the other end of the first resistor of the branch is connected to the output end of the control voltage through two series-connected diodes in sequence; the power detection port of the third detection branch is connected to one end of the first resistor of the branch, and the other end of the first resistor of the branch is connected to the output end of the control voltage after passing through three series-connected diodes in sequence. Of course, this is only an example, and the number of diodes in the specific detection branch can be set and adjusted according to actual application requirements. The different number of diodes in series can change the turn-on voltage of the detection branch, so that different detection branches are limited according to different input powers. Setting the first resistor can avoid damage to the components in the detection branch by instantaneous large current.

[0029] See also Figure 2 Taking a detection branch of the power detection unit as an example, its working principle is: when the RF power voltage exceeds the conduction voltage of the diode D1, the diode D1 is turned on and the capacitor C b Charging, V ctrl The port voltage gradually rises from 0V. Among them, the resistor R1 is a current limiting resistor to prevent the diode D1 from being damaged due to excessive current after it is turned on. b The resistor is a charge discharge resistor. Its function is to discharge the capacitor C when the RF power voltage drops to the diode conduction voltage. b The charge on the ctrl The port voltage returns to 0V. In a 50Ω impedance RF system, for the nth power detection branch, the detected RF power value is P = (n*V dio ) 2 / 50, where V dio is the threshold voltage of the diode, usually 0.7V.

[0030] In one embodiment, the power discharge unit includes multiple parallel discharge branches, wherein each of the discharge branches includes at least one transistor and a second resistor, the gate of each transistor is connected to the input port of the control voltage through a second resistor, and one end of each discharge branch is grounded and the other end is used as a power discharge port. For details, please refer to Figure 3 , Figure 3 : is a circuit diagram of a power discharge unit in an embodiment of the present application. The power discharge unit includes M discharge branches, wherein the first discharge branch includes a transistor and a second resistor, the gate of the transistor is connected to the input end of the power discharge unit through the second resistor, and then receives the control voltage V generated by the power detection unit. ctrl , the source of the transistor is grounded, and the drain serves as the power discharge port of the discharge branch. The second discharge branch includes two transistors and two second resistors, and the gates of the two transistors are respectively connected to the input end of the power discharge unit through a second resistor; the source of one transistor is grounded, and the drain is connected to the source of another transistor, and the drain of the other transistor serves as the power discharge port of the discharge branch. Similarly, the last discharge branch includes M transistors and M second resistors, and the transistors are connected in series in the above manner to form the discharge branch. The gate of the transistor is connected in series with a second resistor, which can be used to isolate the RF signal.

[0031] In one embodiment, the number of transistors connected in series in different discharge branches can be set to be different, and the transistors can be MOS tubes. The power detection unit is connected through V ctrl The port controls the on and off of the MOS tube in the power discharge unit. ctrl When the port is at high voltage, the MOS tube is turned on to discharge the RF power. The power discharge branch needs to be selected according to the power detection branch, and the relationship is: m≥n*V dio / 2*V mos , where m is the number of MOS tubes in series in the power detection branch, n is the number of diodes in series in the power detection branch, V mos is the threshold voltage of the MOS tube, usually 0.5 V. By selecting different power discharge branches, different power discharge on-resistances can be achieved, thereby flexibly adjusting the limited output power.

[0032] See also Figure 4 , Figure 4The first-level reconfigurable power limiter in one embodiment of the present application is an architectural diagram. The first-level reconfigurable power limiter includes a power detection unit and a power discharge unit. The power detection unit includes n power detection ports, and one power detection port is selected to be connected to the RF port through a bonding wire; the power discharge unit includes m power discharge ports, and one power discharge port is selected to be connected to the RF port through a bonding wire. By selecting different power detection ports and power discharge ports, the power limiter circuit reconstruction function can be realized, and the flexible adjustment of the limited output power can be achieved.

[0033] In one embodiment, the present application also provides a multi-stage reconfigurable power limiter, which includes a plurality of the aforementioned reconfigurable power limiters, and the RF ports of the reconfigurable power limiters are cascaded to each other and connected to the RF input and RF output. Figure 5 , Figure 5 This is an architectural diagram of a multi-stage reconfigurable power limiter in one embodiment of the present application. Each stage of the multi-stage reconfigurable power limiter includes a power detection unit and a power discharge unit. The power detection unit includes n power detection ports, and one power detection port is selected to be connected to the RF port of this stage through bonding wires; the power discharge unit includes m power discharge ports, and one power discharge port is selected to be connected to the RF port of this stage through bonding wires. The first-stage RF port is connected to the limiter input, and the two-stage limiters are directly connected through bonding wires. By selecting different power detection ports and power discharge ports in each stage of the limiter unit, the reconstruction function of the multi-stage power limiter can be realized.

[0034] Based on the technical solutions of the above embodiments of the present application, the reconfigurable power limiter is composed of two parts: a power detection unit and a power discharge unit. The power detection unit is used to detect the input power, and is composed of a diode, a resistor and a capacitor. The starting power is set by selecting the number of series diodes of the corresponding port. The power discharge unit is used for RF power discharge, and is composed of a MOS tube and a resistor. The limiting output power is set by selecting the number of cascaded MOS tubes of the corresponding port. Through the cooperation of the power detection unit and the power discharge unit, flexible adjustment of the limiting power is achieved. At the same time, the multi-stage limiter can be reconfigured; the reconfigurable power limiter has the characteristics of flexible and adjustable limiting output power, and can be applied to various RF communication systems. At the same time, by presetting the diode in the power detection unit and the power discharge MOS tube in the power discharge unit, there is no need for multiple tape-outs. The power limiter can be quickly reconstructed by changing the bonding wire during chip packaging.

[0035] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A reconfigurable power limiter, characterized in that: include: A power detection unit, which is selectively connected to the RF port through a plurality of independent power detection ports to detect input power and generate a control voltage according to the input power; A power discharge unit is selectively connected to the radio frequency port through a plurality of mutually independent power discharge ports, and limits the output power of the radio frequency port under the action of the control voltage.

2. The reconfigurable power limiter according to claim 1, characterized in that: The power detection unit includes multiple parallel detection branches, wherein each of the detection branches includes a first resistor and at least one diode connected in series in sequence; the input end of each of the detection branches serves as the power detection port for establishing a connection with the radio frequency port; the output end of each of the detection branches is grounded through a capacitor, and the output end of the detection branch serves as the output port of the control voltage. When any of the detection branches is in the on state, the control voltage is generated by charging the capacitor.

3. The reconfigurable power limiter according to claim 2, characterized in that: The power detection unit further comprises a discharge circuit, one end of which is connected to the output end of each detection branch, and the other end of which is grounded. After power is turned off, the charge in the capacitor is released through the discharge circuit.

4. The reconfigurable power limiter according to claim 2, characterized in that: The numbers of the diodes connected in series in each of the detection branches are different.

5. The reconfigurable power limiter according to claim 1, characterized in that: The power discharge unit includes multiple parallel discharge branches, wherein each of the discharge branches includes at least one transistor and a second resistor, the gate of each of the transistors is connected to the input port of the control voltage through one of the second resistors, and one end of each of the discharge branches is grounded, and the other end serves as a power discharge port.

6. The reconfigurable power limiter according to claim 5, characterized in that: The numbers of transistors connected in series in each of the discharge branches are different.

7. A multi-stage reconfigurable power limiter, characterized in that: include: A plurality of reconfigurable power limiters as claimed in any one of claims 1 to 6, wherein the RF ports of the reconfigurable power limiters are cascaded to each other and connected to the RF input and the RF output.

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