KR102043560B1 - A current-reuse quadrature active mixing circuit - Google Patents

Abstract

A current reuse quadrature active frequency mixing circuit is disclosed. According to an embodiment of the present invention, an active frequency mixing circuit comprises: a quadrature signal generator; and a switch to which one end of the quadrature signal generator is connected so as to share current with the quadrature signal generator. The quadrature signal generator performs a voltage-to-current conversion.

Description

CURRENT-REUSE QUADRATURE ACTIVE MIXING CIRCUIT

The embodiments below relate to a current reuse quadrature active frequency mixing circuit.

In the case of an active mixer, since a direct current (DC) flows to a switching stage, a 1 / f noise is large. To compensate for this, current-bleeding circuits can be added to reduce the DC current flowing through the switching stage.

The embodiments below can provide a technique for lowering power consumption of quadrature active frequency mixing circuits by reusing current.

According to an exemplary embodiment, an active frequency mixing circuit includes a quadrature signal generator, a switch connected to one of the quadrature signal generators and configured to share a current between the quadrature signal generator and the quadrature signal generator. Perform a current conversion.

The quadrature signal generator may include an in phase signal generator and a quadrature phase signal generator.

The in phase signal generator and the quadrature phase signal generator may include a first current source having one end connected to a DC power supply, a first capacitor connected in parallel with the first current source, and connected at one end to the DC power source; A P type metal oxide semiconductor field effect transistor (PMOS FET) having a source connected to the other end of the first current source and the other end of the capacitor, an N type metal oxide semiconductor (NMOS) FET having a drain connected to the drain of the PMOS FET; A second current source having one end connected to the source of the NMOS FET, the other end connected to ground at the other end, and connected in parallel with the second current source, the one end connected to the source of the NMOS FET, and the other end connected to ground; It may include two capacitors.

The source of the PMOS FET of the in phase signal generator and the gate of the PMOS FET of the quadrature phase signal generator are connected, and the source of the NMOS FET of the in phase signal generator and the gate of the NMOS FET of the quadrature phase signal generator are connected. Can be.

The active frequency mixing circuit includes a first DC blocking capacitor connected between the source of the PMOS FET of the in phase signal generator and the gate of the PMOS FET of the quadrature phase signal generator, and the source of the NMOS FET of the in phase signal generator. And a second DC blocking capacitor connected between the gate of the NMOS FET of the quadrature phase signal generator.

The switch may be implemented with a metal oxide semiconductor field effect transistor (MOSFET) or a bipolar junction transistor (BJT).

The source of the switch may be connected together to the drain of the NMOS FET and the drain of the PMOS FET.

In the switch, a local oscillator signal may be applied to a gate.

The active frequency mixing circuit may further include a load connected at one end to a DC power supply and a filter connected to the other end of the load.

The load may be implemented with a MOSFET or a resistor.

The MOSFET may provide a common mode voltage using a feedback resistor, or may provide a common mode voltage using an OP-AMP.

The filter may include a resistor and a capacitor connected in parallel.

One end of the filter may be connected to the drain of the MOSFET, an IF signal may be applied thereto, and the other end thereof may be connected to a gate of the MOSFET.

1 shows an example of a single balanced active mixer including a current bleeding circuit.
2 shows an example of a dual balanced quadrature active mixer circuit.
3 shows a schematic block diagram of an active frequency mixing circuit according to one embodiment.
4 shows a schematic block diagram of the quadrature signal generator shown in FIG. 3.
5 shows an example of a circuit diagram of the active frequency mixing circuit shown in FIG.

Hereinafter, exemplary embodiments will be described in detail with reference to the accompanying drawings. However, various changes may be made to the embodiments so that the scope of the patent application is not limited or limited by these embodiments. It is to be understood that all changes, equivalents, and substitutes for the embodiments are included in the scope of rights.

The terminology used herein is for the purpose of description and should not be construed as limiting. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, terms such as "comprise" or "have" are intended to indicate that there is a feature, number, step, action, component, part, or combination thereof described on the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, components, or a combination thereof.

Terms such as first or second may be used to describe various components, but the components should not be limited by the terms. The terms are for the purpose of distinguishing one component from another component only, for example, without departing from the scope of the rights according to the concepts of the embodiment, the first component may be named a second component, and similarly The second component may also be referred to as the first component.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art. Terms such as those defined in the commonly used dictionaries should be construed as having meanings consistent with the meanings in the context of the related art and shall not be construed in ideal or excessively formal meanings unless expressly defined in this application. Do not.

In addition, in the description with reference to the accompanying drawings, the same components regardless of reference numerals will be given the same reference numerals and duplicate description thereof will be omitted. In the following description of the embodiment, when it is determined that the detailed description of the related known technology may unnecessarily obscure the gist of the embodiment, the detailed description thereof will be omitted.

1 shows an example of a single balanced active mixer including a current bleeding circuit.

Referring to FIG. 1, a single-balanced active mixer may have a large 1 / f noise because DC (direct current) flows to the switching stages M2 and M3. Thus, by adding a current-bleeding circuit such as M4, the DC flowing in the switching stage can be reduced.

Even if a current bleeding circuit is added, DC flowing to M1 can be maintained. Therefore, it is possible to reduce the 1 / f noise of the switching stage while securing the required gm (transconductunce) value of M1. The same applies to current bleeding circuits in double-balanced active mixers.

2 shows an example of a dual balanced quadrature active mixer circuit.

Referring to FIG. 2, a dual balanced quadrature active mixer may generate a quadrature signal in a radio frequency (RF) signal path using a quadrature gm stage. Therefore, the quadrature signal may not be generated in the LO path. Using the circuit of Figure 2 can reduce the current consumption of the LO path.

3 shows a schematic block diagram of an active frequency mixing circuit according to one embodiment.

Referring to FIG. 3, the active frequency mixing circuit 10 may generate a new frequency using a plurality of frequencies. For example, a new signal can be generated by adding, subtracting, multiplying, or dividing a plurality of frequencies.

The active frequency mixing circuit 10 can reduce the DC flowing to the switching stage using a current bleeding circuit. The active frequency mixing circuit 10 may reduce current consumption of the entire circuit by reusing the current flowing in the current bleeding circuit.

The active frequency mixing circuit 10 can increase the effective gm of the gm stage by reusing the current bleeding circuit for RF voltage to current conversion to achieve higher gain and lower noise figure.

The active frequency mixing circuit 10 may be applied to IoT applications requiring low power, such as biomedical (MICS, MedRadio applications), WPAN (Zigbee, Bluetooth), Wifi-ah, NB-IoT, and LTE-M.

The active frequency mixing circuit 10 may reuse the current bleeding circuit to generate a quadrature signal in the RF domain and perform an RF voltage-to-current conversion function. The active frequency mixing circuit 10 can obtain a high gain and a low noise figure by increasing the effective gm of the active mixer with the same current consumption. In addition, quadrature signals may be generated in the RF signal path.

The active frequency mixing circuit 10 may have improved voltage gain, noise figure and 1 / f noise performance with the same current consumption. In the Internet of Things (IoT), low-power receiver design is key. Using active frequency mixing circuits 10, high-performance quadrature mixers can be built at low power, making them suitable for IoT applications.

The active frequency mixing circuit 10 can lower the power consumption of the entire transceiver since it does not need to provide quadrature signals in the LO path.

The active frequency mixing circuit 10 serves to reduce the DC of the switching stage in the DC domain, and may perform RF voltage-to-current conversion in the RF domain.

The active frequency mixing circuit 10 includes a switch 300 and a quadrature signal generator 400. The active frequency mixing circuit 10 may further include a rod 100 and a filter 200.

The load 100 may be implemented with a PMOS FET or resistor. The load 100 can be connected to a DC power source.

The filter 200 may filter an unintended signal. For example, the filter 200 may filter noise and out-of-band blockers. In addition, the filter 200 may perform channel selection.

The quadrature signal generator 400 may generate a quadrature signal. The quadrature signal generator 400 may perform voltage-to-current conversion.

The switch 300 may be connected to one end of the quadrature signal generator 400 so that current may be distributed with the quadrature signal generator 400.

The switch 300 may be implemented as a metal oxide semiconductor field effect transistor (MOSFET) or a bipolar junction transistor (BJT).

4 shows a schematic block diagram of the quadrature signal generator shown in FIG. 3.

Referring to FIG. 4, the quadrature signal generator 400 may include an in phase signal generator 410 and a quadrature phase signal generator 430.

The in phase signal generator 410 may generate an in phase signal, and the quadrature phase signal generator 430 may generate a quadrature phase signal.

The in phase signal generator 410 and the quadrature phase signal generator 430 may reduce the DC flowing through the switch 300 by distributing a current flowing through the switch 300.

5 shows an example of a circuit diagram of the active frequency mixing circuit shown in FIG.

Referring to FIG. 5, the source of the switch 300 may be connected together to the drain of the NMOS FET and the drain of the PMOS FET. A local oscillator signal may be applied to the gate of the switch 300.

One end of the load 100 may be connected to a DC power supply. The load 100 may be implemented with a MOSFET or a resistor. The MOSFET of the load 100 may provide a common mode voltage using a feedback resistor or provide a common mode voltage using an operational amplifier (OP-AMP).

The filter 200 may be connected to the other end of the rod 100. The filter 200 may include a resistor and a capacitor connected in parallel. One end of the filter 200 may be connected to the drain of the MOSFET of the load 100 to receive an IF signal, and the other end of the filter 200 may be connected to the gate of the MOSFET of the load 100.

As illustrated in FIG. 5, the filter 200 may include R _L and C _L. In the example of FIG. 5, the filter may be a low pass filter (LPF).

In the example of FIG. 5, M _N3 , M _N4 , M _N5 , and M _N6 may configure a switching stage, and M _P3 , M _P4 , M _P5 , and M _P6 may configure an IF stage.

The in phase signal generator 410 and the quadrature phase signal generator 430 may include a first current source having one end connected to a DC power supply, a first capacitor connected at one end with a first current source in parallel, And a P type metal oxide semiconductor field effect transistor (PMOS FET) connected to the other end of the first current source and the other end of the capacitor. The first current source may be implemented with a resistor.

The in phase signal generator 410 and the quadrature phase signal generator 430 have one end connected to a source of an NMOS (N type) metal oxide semiconductor (NMOS) FET and an NMOS FET having a drain connected to a drain of the PMOS FET. And a second capacitor connected in parallel with the second current source and the second current source connected to ground, one end connected to the source of the NMOS FET, and the other end connected to the ground. The second current source may be implemented with a resistor.

In the example of FIG. 5, M _N1 and M _P1 may constitute a gm stay of the in-phase signal generator 410, and M _N2 and M _P2 may constitute a gm stage of the quadrature phase signal generator 430. M _P1 , M _P2 − may serve as gm stages and simultaneously serve as current bleeding circuits.

M _P1 , M _P2 -and IP may perform voltage-to-current conversion in the RF region, and reduce DC current flowing to the switching stage in the DC region.

In-phase signal generator 410 and quadrature phase signal generator 430 are current bleeding circuits that remove DC currents of M _N1 and M _N2 to remove 1 / f noise and simultaneously increase quadrature signals while increasing effective gm. Can be generated.

The voltage V _in input to the gates of M _N1 and M _P1 may be an RF voltage V _RF . M _N1 , M _N2 , M _P1 , M _P2 , C _N1 , C _N2 , C _P1 and C _P2 can receive a RF voltage and generate quadrature current as an output signal.

Since the current output of the gm stage is quadrature, it may not be necessary to create a quadrature signal in the LO path. Effective gm can be increased because the current bleeding circuit also plays a role of voltage-to-current conversion at the gm stage. In addition, the effective gm is increased so that the active frequency mixing circuit 10 can achieve high gain and low noise figure.

In-phase signal generator 410 and quadrature phase signal generator 430 may include current sources I _P , I _N and capacitors C _P1 , C _P2 , C _N1 , C _N2 , respectively. Current sources and capacitors can generate quadrature signals.

One side of I _P , C _P1 , C _P2 may be connected to a DC power supply, and one side of IN and C _N1 , C _N2 may be connected to ground.

The source of the PMOS FET of the in phase signal generator 410 and the gate of the PMOS FET of the quadrature phase signal generator 430 may be connected. The source of the NMOS FET of the in phase signal generator 410 and the gate of the NMOS FET of the quadrature phase signal generator 430 may be connected.

The active frequency mixing circuit 10 is coupled between the source of the PMOS FET of the in phase signal generator 410 and the gate of the PMOS FET of the quadrature phase signal generator 430 and the NMOS of the in phase signal generator. And a second DC blocking capacitor connected between the source of the FET and the gate of the NMOS FET of the quadrature phase signal generator.

The first DC blocking capacitor and the second DC blocking capacitor may operate like a shorted wiring in view of alternating current.

The active frequency mixing circuit 10 may be a single balanced active mixer that receives a single-ended input and generates a quadrature IF signal. Since the active frequency mixing circuit 10 generates the quadrature signal at the gm stage of the active mixer, the quadrature signal may not be generated in the LO path for quadrature mixing.

 Therefore, the LO path does not require a block to generate quadrature signals, such as a divide-by-2, polyphase filter, or quadrature voltage controlled oscillator (VCO). Minimize current consumption at.

Although a single-balanced active quadrature mixer is shown in the example of FIG. 5, the active frequency mixing circuit 10 can be extended to a double-balanced active quadrature mixer. have.

In addition, the active frequency mixing circuit 10 may further include a circuit for compensating for the magnitude and phase mismatch of the quadrature signal due to parasitic capacitance at a high frequency.

Method according to the embodiment is implemented in the form of program instructions that can be executed by various computer means may be recorded on a computer readable medium. The computer readable medium may include program instructions, data files, data structures, and the like, alone or in combination. The program instructions recorded on the media may be those specially designed and constructed for the purposes of the embodiments, or they may be of the kind well-known and available to those having skill in the computer software arts. Examples of computer readable recording media include magnetic media such as hard disks, floppy disks and magnetic tape, optical media such as CD-ROMs, DVDs, and magnetic disks such as floppy disks. Magneto-optical media, and hardware devices specifically configured to store and execute program instructions, such as ROM, RAM, flash memory, and the like. Examples of program instructions include machine code, such as produced by a compiler, as well as high-level language code that can be executed by a computer using an interpreter or the like. The hardware device described above may be configured to operate as one or more software modules to perform the operations of the embodiments, and vice versa.

The software may include a computer program, code, instructions, or a combination of one or more of the above, and configure the processing device to operate as desired, or process independently or collectively. You can command the device. Software and / or data may be any type of machine, component, physical device, virtual equipment, computer storage medium or device in order to be interpreted by or to provide instructions or data to the processing device. Or may be permanently or temporarily embodied in a signal wave to be transmitted. The software may be distributed over networked computer systems so that they are stored or executed in a distributed manner. Software and data may be stored on one or more computer readable recording media.

Although the embodiments have been described with reference to the accompanying drawings, those skilled in the art may apply various technical modifications and variations based on the above. For example, the described techniques may be performed in a different order than the described method, and / or components of the described systems, structures, devices, circuits, etc. may be combined or combined in a different form than the described method, or other components. Or even if replaced or substituted by equivalents, an appropriate result can be achieved.

Therefore, other implementations, other embodiments, and equivalents to the claims are within the scope of the following claims.

Claims (13)

Quadrature signal generator;
A switch having one end connected to an output terminal of the quadrature signal generator such that current is shared with the quadrature signal generator;
Including,
The quadrature signal generator performs a voltage-to-current conversion,
The input of the switch is a local oscillator (LO) signal, and the input of the quadrature signal generator is a radio frequency (RF).
Active frequency mixing circuit.
The method of claim 1,
The quadrature signal generator,
Including an in phase signal generator and a quadrature phase signal generator
Active frequency mixing circuit.
The method of claim 2,
The in phase signal generator and the quadrature phase signal generator,
A first current source having one end connected to the DC power supply;
A first capacitor connected in parallel with the first current source and having one end connected to the DC power supply;
A P type metal oxide semiconductor field effect transistor (PMOS FET) having a source connected to the other end of the first current source and the other end of the capacitor;
An NMOS metal oxide semiconductor (NMOS) FET having a drain connected to a drain of the PMOS FET; And
A second current source having one end connected to a source of the NMOS FET and the other end connected to ground; And
A second capacitor connected in parallel with the second current source, one end of which is connected to a source of the NMOS FET, and the other end of which is connected to ground
Active frequency mixing circuit comprising a.
The method of claim 3,
A source of the PMOS FET of the in phase signal generator and a gate of the PMOS FET of the quadrature phase signal generator are connected,
The source of the NMOS FET of the in phase signal generator and the gate of the NMOS FET of the quadrature phase signal generator are connected.
Active frequency mixing circuit.
The method of claim 4, wherein
A first DC blocking capacitor coupled between the source of the PMOS FET of the in phase signal generator and the gate of the PMOS FET of the quadrature phase signal generator; And
A second DC blocking capacitor connected between the source of the NMOS FET of the in phase signal generator and the gate of the NMOS FET of the quadrature phase signal generator
Active frequency mixing circuit further comprising.
The method of claim 3,
The switch,
Implemented as a Metal Oxide Semiconductor Field Effect Transistor (MOSFET) or Bipolar Junction Transistor (BJT),
Active frequency mixing circuit
The method of claim 6,
The source of the switch is connected together to the drain of the NMOS FET and the drain of the PMOS FET.
Active frequency mixing circuit.
The method of claim 6,
The switch,
Local Oscillator signal is applied to the gate
Active frequency mixing circuit.
The method of claim 1,
A load, one end of which is connected to a DC power supply; And
A filter connected to the other end of the rod
Active frequency mixing circuit further comprising.
The method of claim 9,
The rod is,
Implemented with MOSFET or resistor
Active frequency mixing circuit.
The method of claim 10,
The MOSFET,
Provide a common-mode voltage using a feedback resistor, or
Using OP-AMP to provide common mode voltage
Active frequency mixing circuit.
The method of claim 9,
The filter,
Paralleled Resistors and Capacitors
Active frequency mixing circuit comprising a.
The method of claim 10,
The filter,
One end is connected to the drain of the MOSFET, an IF signal is applied, and the other end is connected to the gate of the MOSFET.
Active frequency mixing circuit.

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