CN117378089A

CN117378089A - Four-port circulator

Info

Publication number: CN117378089A
Application number: CN202180098664.4A
Authority: CN
Inventors: 德罗尔·雷格夫; 希米·西隆; 多伦·埃兹里
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2021-06-15
Filing date: 2021-06-15
Publication date: 2024-01-09
Also published as: EP4342024A1; WO2022262943A1

Abstract

An orthogonal circulator device includes a four-port quasi-circulator and a four-port orthogonal mixer connected in cascade. The scattering matrix of the quasi-circulator is S1:the scattering matrix of the quadrature mixer is S2:the fourth port of the quasi-circulator is connected to the fourth port of the quadrature mixer and the third port of the quasi-circulator is connected to the first port of the quadrature mixer.

Description

Four-port circulator

Background

Some embodiments described in the present disclosure relate to quadrature circulators, and in particular, but not exclusively, to four-port electronic quadrature circulators.

Currently, an implementation of electronic circulator self-interference cancellation (Electronic Circulator self-interference cancellation, SIC) is to couple the Transmit (TX) signal into a finite impulse response (finite impulse response, FIR) filter to shape the post Power Amplifier (PA) and combine the cancellation signal pre-low noise amplifier (low noise amplifier, LNA). These schemes are complex and cannot be extended to multiple-input and multiple-output (MIMO) systems where self-interference and mutual interference exist, and generate transmission and reception losses, reducing power efficiency and receiver signal-to-noise ratio.

Simultaneous transmit receive (Simultaneous Transmit Receive, STR) single transmit/receive antenna wireless communication scenarios such as Full Duplex (FD) or frequency division Duplex (Frequency Division Duplex, FDD) without a duplexer require a transmit-receive SIC mechanism. Most implementations of SIC are done between TX transmit output and RX receive input, loading the TX and RX channels, reducing power efficiency and signal-to-noise ratio.

Disclosure of Invention

The present invention is directed to a four port circulator and a method of using a four port circulator for Radio Frequency (RF) communication.

The embodiment of the invention provides a four-port circulator with lossless receiving and SIC transmission functions. The four-port circulator (also referred to herein as an orthogonal circulator) includes a non-ideal four-point circulator (referred to herein as a quasi-circulator) cascaded with an orthogonal mixer. The two ports of the quasi-circulator are connected to the two ports of the quadrature mixer, respectively. The quadrature mixer perfectly recovers the non-ideal characteristics of the quasi-circulator, creating a new transfer function for the ideal electronic quadrature circulator.

An embodiment of the orthogonal circulator has the following transfer coefficients:

transfer coefficient of port 1 to port 2 = 1;

transfer coefficient port 2 to port 3 = 1;

transfer coefficient port 3 to port 4 = 1;

transfer coefficient port 4 to port 1 = 1.

All other pairs of ports are isolated from each other. These transfer coefficients are represented in the following scattering matrix:

advantages of the orthogonal circulators presented herein include:

(a) Size and on-chip integration compatibility—it is a small form factor electronic device relative to the cumbersome magnetic devices currently available;

(b) Complete transmission between successive ports, no power loss;

(c) RF front ends suitable for full-Duplex (FD), half-Duplex (HD) and frequency division Duplex (Frequency Division-Duplex, FDD) communications;

(d) The method comprises a built-in fourth port, no loss exists in an RX port, and SIC can be realized in FD and FDD applications;

(e) The fourth port can also realize mutual interference elimination of nearby antennas in MIMO operation;

(f) Suitable for TX carrier aggregation concurrent with FD, HD or FDD.

The above and other objects are achieved by the features of the independent claims. Other implementations are apparent in the dependent claims, the description and the drawings.

A first aspect of the present invention provides an orthogonal circulator device comprising:

quasi-circulator (100), comprising:

the first port, the second port, the third port and the fourth port, wherein the scattering matrix S1 of the quasi-circulator is expressed as:

wherein each element S1 in the scattering matrix S1 _xy A portion representing the square root of the power of the signal directed by the quasi-circulator from the y-th port to the x-th port, where x and y can be 1, 2, 3 and 4 and x is not equal to y, each element S1 _xx A portion representing the square root of the power of the signal reflected at the x-th port;

an orthogonal mixer comprising a first port, a second port, a third port and a fourth port, wherein a scattering matrix S2 of the orthogonal mixer is expressed as:

wherein each element S2 in the scattering matrix S2 _xy A portion representing the square root of the power of the signal directed by the quadrature mixer from the y-th port to the x-th port, where x and y can be 1, 2, 3 and 4 and x is not equal to y, each element S2 _xx Representing a portion of the square root of the power of the signal reflected at the x-th port,

wherein the fourth port of the quasi-circulator is connected to the fourth port of the quadrature mixer and the third port of the quasi-circulator is connected to the first port of the quadrature mixer.

The advantage of the first aspect is that an orthogonal circulator with small physical dimensions and ideal transfer function is obtained.

In one implementation manner of the first aspect, the quasi-circulator includes:

a first 90 degree reciprocal phase shifter (reciprocal phase shifter, RPS) between the first port of the quasi-circulator and the second port of the quasi-circulator;

a second 90 degree RPS between the second port of the quasi-circulator and the third port of the quasi-circulator;

a 90 degree non-reciprocal phase shifter (non-reciprocal phase shifter, NRPS) between the third port of the quasi-circulator and the fourth port of the quasi-circulator;

a third 90 degree RPS between the fourth port of the quasi-circulator and the first port of the quasi-circulator;

wherein the characteristic impedance of the first RPS is a first value equal to the impedance of the first port of the quasi-circulator, and the characteristic impedance of the second RPS and the third RPS is a second value, wherein the second value is equal to the first value divided by the second valueIn another implementation of the first aspect, the NRPS is impedance transparent. In another implementation of the first aspect, the phase of the forward signal path from the first port of the quasi-circulator through the second port of the quasi-circulator to the third port of the quasi-circulator is 180 degrees, and the phase of the forward signal path from the first port of the quasi-circulator through the fourth port of the quasi-circulator to the third port of the quasi-circulator is 0 degrees.

The benefit of these implementations is to provide a four port device with the transfer function required for a quasi-circulator.

In another implementation of the first aspect, the orthogonal circulator device further includes an antenna connected to a second port of the quasi-circulator. The benefit of this implementation is that the orthogonal circulator ports can be used in wireless communication devices.

In another implementation of the first aspect, the quadrature circulator device further comprises a first reflective element, wherein an output of the first reflective element is connected to a third port of the quadrature mixer. Thus, the self-interference cancellation signal may be input to port 3 of the quadrature circulator device, while the signal from port 2 is passed to port 4. The benefit of this implementation is that it is applicable to many modes of communication, such as full duplex, half duplex and frequency division duplex.

In another implementation of the first aspect, the quadrature circulator device further comprises a second reflective element, wherein an output of the second reflective element is connected to the first port of the quasi-circulator. Thus, the transmitted signal can be input to port 1 and port 4 of the quadrature circulator. The benefit of this implementation is that it is applicable to carrier aggregation communications.

A second aspect of the invention provides a method of operating an orthogonal circulator device by:

inputting a first Radio Frequency (RF) signal to one of a first port of a quasi-circulator, a second port of the quadrature mixer, and a third port of the quadrature mixer;

a second Radio Frequency (RF) signal is output from one of the first port of the quasi-circulator, the second port of the quadrature mixer, and the third port of the quadrature mixer.

The benefit of this aspect is that the quadrature circulator can be used as part of the RF front-end for many forms of RF communications and system architecture.

In one implementation of the second aspect, the orthogonal circulator device operates by:

inputting a transmission signal at a first port of the quasi-circulator;

inputting a signal received from an antenna connected to a second port of the quasi-circulator and outputting a transmission signal to the antenna;

a self-interference cancellation (self-interference cancellation, SIC) signal is input at a third port of the quadrature mixer through a reflective element;

the received signal is output from the second port of the quadrature mixer. The benefit of this implementation is that it is suitable for use in RF front-ends for full duplex communications.

In another implementation of the second aspect, the orthogonal circulator device operates by:

inputting a transmission signal at a first port of the quasi-circulator;

reflecting the received signal at a third port of the quadrature mixer by a reflecting element connected to the third port of the quadrature mixer;

the received signal is output from the second port of the quadrature mixer. The benefit of this implementation is that it is applicable to RF front ends for half duplex communications.

inputting a transmit signal in a first frequency band at a first port of a quasi-circulator;

inputting a signal in a second frequency band received from an antenna connected to a second port of the quasi-circulator, and outputting a transmission signal to the antenna;

the received signal is output from the second port of the quadrature mixer. The benefit of this implementation is that it is applicable to RF front ends for frequency division duplex communications.

inputting a first transmission signal in a first frequency band at a first port of the quasi-circulator through a reflective element;

inputting a second transmission signal in a second frequency band at a second port of the quadrature mixer;

the first transmit signal and the second transmit signal are output from a second port of the quasi-circulator. The benefit of this implementation is that it is applicable to RF front ends for carrier aggregation communications.

Other systems, methods, features and advantages of the invention will be or will become apparent to one with skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods, features and advantages be included within this description, be within the scope of the invention, and be protected by the accompanying claims.

Unless defined otherwise, all technical and/or scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the examples pertain. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of the embodiments, the exemplary methods and/or materials are described below. In case of conflict, the present specification, including definitions, will control. In addition, these materials, methods, and examples are illustrative only and not necessarily limiting.

Drawings

Some embodiments are described herein, by way of example only, in connection with the accompanying drawings. The details shown are merely examples and are provided for illustrative purposes to discuss embodiments, with specific reference being made to the details of the drawings. Thus, it will be apparent to those skilled in the art how to practice the embodiments from the description of the figures.

In the drawings:

fig. 1 is a schematic block diagram of a quadrature circulator according to an embodiment of the invention;

fig. 2 is a schematic diagram of a simulated quadrature circulator;

FIG. 3 is a schematic diagram of a quasi-circulator reflecting the S1 transfer coefficient;

fig. 4 is a simplified block diagram of a quasi-circulator according to an exemplary embodiment of the invention;

FIG. 5 is a schematic diagram of an exemplary quadrature mixer according to an exemplary embodiment of the present invention;

fig. 6 is a schematic block diagram of an RF front-end for full-duplex (FD) communication according to an exemplary embodiment of the present invention;

fig. 7 is a schematic block diagram of an RF front end for half-duplex (HD) communication according to an exemplary embodiment of the invention;

fig. 8 is a schematic block diagram of an RF front-end for frequency division Duplex (Frequency Division-Duplex, FDD) communication in accordance with an exemplary embodiment of the present invention;

fig. 9 is a schematic block diagram of an RF front-end for MIMO communication according to an exemplary embodiment of the present invention;

fig. 10 is a schematic block diagram of an RF front-end for carrier aggregation communication in accordance with an exemplary embodiment of the present invention;

fig. 11 and 12 are schematic block diagrams of an RF front-end for carrier aggregation communication and concurrent full duplex operation according to respective exemplary embodiments of the present invention.

Detailed Description

The embodiment of the invention provides a lossless and perfectly matched orthogonal circulator. The quadrature circulator includes a quasi-circulator cascaded with a quadrature mixer as described herein.

Before explaining at least one embodiment in detail, it is to be understood that the embodiment is not necessarily limited in its application to the details of construction and the arrangement of components and/or methods set forth in the following description and/or drawings and/or examples. Implementations described herein support other embodiments, or are supported for practice or execution in various ways.

Embodiments may be a system, method, and/or computer program product. The computer program product may include one or more computer-readable storage media having computer-readable program instructions that cause a processor to perform aspects of the embodiments.

The computer readable storage medium may be a tangible device that can retain and store instructions for use by an instruction execution device. The computer readable storage medium may include, but is not limited to, electronic storage, magnetic storage, optical storage, electromagnetic storage, semiconductor storage, or any suitable combination of the foregoing, and the like. A non-exhaustive list of more specific examples of the computer readable storage medium would include: portable computer floppy disk, hard disk, random access memory (random access memory, RAM), read-only memory (ROM), erasable programmable read-only memory (erasable programmable read-only memory, EPROM or flash memory), static random access memory (static random access memory, SRAM), compact disc-only (compact disc read-only memory, CD-ROM), digital versatile disc (digital versatiledisk, DVD), memory stick, floppy disk, and any suitable combination of the foregoing. Computer-readable storage media, as used herein, should not be construed as transitory signals per se, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through waveguides or other transmission media (e.g., optical pulses through fiber optic cables), or electrical signals transmitted through wires.

The computer readable program instructions described herein may be downloaded from a computer readable storage medium to a corresponding computing/processing device or over a network such as the internet, a local area network, a wide area network, and/or a wireless network to an external computer or external storage device. The network may include copper transmission cables, transmission fibers, wireless transmissions, routers, firewalls, switches, gateway computers and/or edge servers. A network adapter card or network interface in each computing/processing device receives the computer readable program instructions from the network and forwards the computer readable program instructions to store the computer readable program instructions in a computer readable storage medium within the respective computing/processing device.

The computer readable program instructions for performing the operations in an embodiment may be assembler instructions, instruction-set-architecture (ISA) instructions, machine-related instructions, microcode, firmware instructions, state setting data, or source code or object code written in any combination of one or more programming languages. These programming languages include object oriented programming languages, such as Smalltalk, c++, etc., as well as conventional procedural programming languages, such as the "C" programming language or similar programming languages. The computer readable program instructions may be executed entirely on the user's computer, partly on the user's computer; the software package may be executed in part on the user's computer and in part on a remote computer, or entirely on the remote computer or server. In the latter scenario, the remote computer may be connected to the user's computer through any type of network, including a local area network (local area network, LAN) or a wide area network (wide area network, WAN), and the connection may be made to an external computer (for example, through the Internet using an Internet service provider). In some embodiments, electronic circuitry, including programmable logic circuitry, field-programmable gate array (FPGA), or programmable logic array (programmable logic array, PLA), or the like, may execute the computer-readable program instructions to customize the electronic circuitry by using state information of the computer-readable program instructions to perform various aspects of the embodiments.

Various aspects of the embodiments are described herein in connection with flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to the embodiments. It will be understood that each block of the flowchart illustrations and/or block diagrams, and combinations of blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer-readable program instructions.

These computer readable program instructions may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks. These computer readable program instructions may also be stored in a computer readable storage medium that can direct a computer, programmable data processing apparatus, and/or other devices to function in a particular manner, such that the computer readable storage medium having instructions stored therein includes articles of manufacture including instructions for implementing the various aspects of the functions/acts specified in the flowchart and/or block diagram block or blocks.

The computer readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other devices to cause a series of operational steps to be performed on the computer, other programmable apparatus or other devices to produce a computer implemented process such that the instructions which execute on the computer, other programmable apparatus or other devices implement the functions/acts specified in the flowchart and/or block diagram block or blocks.

The flowcharts and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to various embodiments. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of instructions, which comprises one or more executable instructions for implementing the specified logical function(s). In some alternative implementations, the functions noted in the block may be implemented out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems which perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.

Referring now to fig. 1, fig. 1 is a schematic block diagram of a quadrature circulator according to an embodiment of the invention. The quadrature circulator 10 includes a quasi-circulator 100 and a quadrature mixer 150, and the quasi-circulator 100 and the quadrature mixer 150 are cascade-connected. Quasi-circulator 100 and quadrature hybrid 150 have the same characteristic impedance Z ₀ 。

I. Orthogonal circulator

The quadrature circulator 10 includes a quasi-circulator 100 and a quadrature mixer 150.

Quasi-circulator 100 has four ports: a first port (101), a second port (102), a third port (103) and a fourth port (104). The quadrature mixer (150) has four ports: a first port (151), a second port (152), a third port (153) and a fourth port (154). The fourth port (104) of the quasi-circulator is connected to the fourth port (154) of the quadrature mixer and the third port (103) of the quasi-circulator is connected to the first port (151) of the quadrature mixer.

The remaining four ports (ports 101, 102, 152 and 153) are used as ports of the orthogonal circulator (10), as follows:

(a) The first port of the quasi-circulator (101) is used as port 1 of the orthogonal circulator (10);

(b) The second port of the quasi-circulator (102) serves as port 2 of the orthogonal circulator (10);

(c) The third port of the quadrature mixer (153) serves as port 3 of the quadrature circulator (10);

(d) The second port of the quadrature mixer (152) serves as port 4 of the quadrature circulator (10).

Port 1, port 2, port 3 and port 4 as used herein represent four ports of an orthogonal circulator.

The scattering matrix (S1) of quasi-circulator 100 is:

each element S1 in S1 _xy Representing a portion of the square root of the power of a signal directed by the quasi-circulator (100) from the y-th port to the x-th port, where x and y may be 1, 2, 3 and 4 and x is not equal to y, each element S1 _xx Representing a portion of the square root of the power of the signal reflected at the x-th port.

The scattering matrix (S2) of the quadrature mixer 150 is:

similar to the representation of S1, each element S2 in S2 _xy Representing a portion of the square root of the power of a signal directed by an quadrature mixer (150) from the y-th port to the x-th port of the quadrature mixer, where x and y can be 1, 2, 3 and 4 and x is not equal to y, each element S2 _xx Representing a fraction of the square root of the power of the signal reflected at the x-th port of the quadrature mixer.

Surprisingly, the inventors found that the signal entering port 3 is completely transmitted to port 4 of the quadrature circulator (10). Nonetheless, the reflection coefficient of quasi-circulator ports 103 and 104 is-1/2, and the transfer coefficients between ports 103 and 104 and between ports 104 and 103 are-j/2 and j/2, respectively. While quadrature mixer 150 equally divides the signal entering port 3 in amplitude, the skilled person will not infer that these two signal parts will add perfectly at port 4. It is also unexpected that the signal entering port 4 will be reconstructed at port 1 because the reflection coefficients of quasi-circulator ports 103 and 104 are-1/2.

In fact, the orthogonal circulator (10) achieves the ideal scattering matrix:

wherein each element |S _{4-Port_circ-XY} I represents a portion of the square root of the power of a signal directed by the orthogonal circulator (10) from port X to port Y of the orthogonal circulator (10), where X and Y may be 1, 2, 3 and 4, and X is not equal to Y, each element I S _{4-Port_circ-XX} The i represents a fraction of the square root of the power of the signal reflected at port X of the quadrature circulator (10). From |S _{4-Port_circ} It can be seen that the orthogonal circulator (10) achieves port-to-port "round robin" full transmission in one direction, zero transmission in the opposite direction, and zero transmission for non-adjacent ports, with perfect matching at all ports.

These results were validated by mersen (Mason) flow chart analysis and simulation. Fig. 2 is a schematic diagram of a simulated quadrature circulator. Both the meisen flow diagram analysis and simulation results indicate that cascading quasi-circulators with quadrature mixers produces the above |s _{4-Port_circ-XY} | a. The invention relates to a method for producing a fibre-reinforced plastic composite. In particular, an ideal transmission between port 4 and port 3 (i.e.)。

Techniques for implementing an orthogonal circulator (10) include, but are not limited to:

(a) Discrete electronic components on a printed circuit board (printed circuit board, PCB);

(b) A fast electromechanical switch integrated with the transmission line;

(c) Gallium arsenide (GaAs);

(d) Gallium nitride (GaN);

(e) Silicon-germanium (SiGe);

(f) Complementary metal-oxide-semiconductor (CMOS);

(d) Optoelectronic and optical devices.

Alternatively, the quadrature circulator is designed to operate in a frequency band of 10MHz to 100 GHz. Alternatively or additionally, the orthogonal circulator operates in the optical frequency.

The orthogonal circulator 10 may be integrated into and used with many types of communication system architectures. Exemplary embodiments of communication techniques utilizing these architectures are presented below.

Optionally, port 2 of the quadrature circulator is used to connect the antenna.

Optionally, port 3 of the quadrature circulator is used to connect the reflective element. Alternatively or additionally, port 1 of the quadrature circulator is used to connect to a reflective element.

The term "reflective element" as used herein refers to a circuit element that reflects a signal passing from a previous port to a next port. Optionally, the reflective element has an input for passing an input signal (e.g., a SIC signal) to the port to which the reflective element is connected.

Examples of reflective elements include, but are not limited to:

(1) A reflected power amplifier;

(2) A reflective isolator;

(3) A reflective buffer.

Alternatively, port 4 of the quadrature circulator is used to connect to a circuit element that can implement carrier aggregation through full-duplex (FD) communication. Examples of such circuit elements include, but are not limited to:

(1) A quadrature balanced power amplifier (Quadrature Balanced Power Amplifier, QBPA);

(2) A second orthogonal circulator.

An exemplary embodiment is described below in connection with fig. 11 and 12.

Examples of QBPA are described in PCT patent application PCT/EP2020/066423, the entire contents of which are incorporated herein by reference.

II, quasi-circulator

Referring now to fig. 3, fig. 3 is a schematic diagram of a quasi-circulator with a scattering matrix S1. Quasi-circulators have non-ideal transfer between most pairs of ports 101 to 104, with reflection at ports 103 and 104.

Referring now to fig. 4, fig. 4 is a simplified block diagram of a quasi-circulator according to an exemplary embodiment of the invention. Quasi-circulator 400 includes a first port 401, a second port 402, a third port 403, and a fourth port 404. The port impedances are all Z ₀ 。

A phase shifter is an electronic device that changes the phase of a propagating signal. Reciprocal phase shifters (reciprocal phase shifter, RPSs) introduce the same phase shift into the bi-directionally propagated signal. Non-reciprocal phase shifters (non-reciprocal phase shifter, NRPS) introduce different phase shifts into the signal propagating in opposite directions.

In addition, the quadrature quasi-circulator device 400 also includes a first 90-degree RPS 405 between the first port 401 and the second port 402, a second 90-degree RPS 406 between the second port 402 and the third port 403, a 90-degree NRPS 407 between the third port 403 and the fourth port 404, and a third 90-degree RPS 408 between the fourth port 404 and the first port 401. According to an embodiment of the invention, the third port 403 and/or the fourth port 404 are isolated from the first port 401. Specifically, the characteristic impedance of the first RPS 405 is a first value, and the characteristic impedance of the second RPS 406 and the third PRS 408 is a second value, where the second value is equal to the first value divided by v 2 (square root of 2). Specifically, the first value, i.e., the characteristic impedance of the first RPS 405, is equal to the impedance of the first port 401 (i.e., the port impedance).

It is noted that, according to some embodiments, the phase of the forward signal path from the first port 401 through the second port 402 to the third port 403 is 180 degrees due to the-90 degree RPS 405 and the-90 degree RPS 406. Similarly, the phase of the forward signal path from the first port 401 through the fourth port 404 to the third port 403 is 0 degrees due to the 90 degree NRPS 407 and the-90 degree RPS 408.

The NRPS 407 (between the third port 403 and the fourth port 404) is "impedance transparent". Typically, the four ports (401 to 404) of the quasi-circulator 400 have the same impedance value, for example, the common value of the impedances is 50 ohms. However, other impedance values may be used.

Quadrature mixer

Quadrature mixers are four-port devices that divide the input signal at one of the ports equally between two output ports that are 90 degrees out of phase. When the quadrature signal is input to two of the ports, the quadrature signal is constructively combined at one of the ports and destructively combined at the other port. Quadrature hybrids are symmetric devices in which each port can be used as an input and/or output port. Many implementations of quadrature mixers are known in the art.

Fig. 5 is a schematic diagram of an exemplary quadrature mixer. The quadrature mixer comprises a characteristic impedance Z ₀ Is Z ₀ Two other branches of/. V2. According to S2 above, the quadrature hybrid 300 desirably distributes input power equally between two of the other three ports, with the remaining ports being fully isolated.

Operation of orthogonal circulators

In some embodiments of the present invention, a Radio Frequency (RF) signal is input to one of the orthogonal circulator ports, and an RF signal is output from at least one of the orthogonal circulator ports, as shown in fig. 6 through 11.

In some exemplary embodiments described herein, the reflective element is a reflective power amplifier. Other embodiments may use different types of one or more reflective elements, such as one or more reflective isolators.

IV.1. RF front end for full duplex communication (RFfrontend, RFFE)

Referring now to fig. 6, fig. 6 is a schematic block diagram of an RF front end for full-duplex (FD) communication according to an exemplary embodiment of the present invention. The signal to be transmitted is input to port 1. The received signal is input to port 2 and the sic signal is input to port 3. Port 4 is the RX output.

Port 2 of the quadrature circulator 610 is connected to an antenna. Port 3 of the quadrature circulator 610 is connected to the output of a reflective SIC amplifier 620 (or alternatively, an isolator). Port 3 is totally reflective and serves as a SIC input which directs its full power to RX port 4 to cancelTX leakage. Port 3 and port 4 are both isolated from the TX signal of port 1 (S ₄₁ ＝0，S ₃₁ ＝0)。

IV.2. RF front end for half duplex communication

Referring now to fig. 7, fig. 7 is a schematic block diagram of an RF front end for half-duplex (HD) communications according to an exemplary embodiment of the invention. Port 2 of the quadrature circulator 710 is connected to an antenna. Port 3 of the quadrature circulator 710 is connected to the output of the reflection SIC amplifier 720. In transmit mode, the TX input of port 1 is passed entirely to the antenna. In RX mode, all antenna input signal power is reflected at port 3 and directed to port 4.

IV.3. RF front-end for frequency division Duplex (Frequency Division-Duplex, FDD) communication

Referring now to fig. 8, fig. 8 is a schematic block diagram of an RF front-end for frequency division Duplex (Frequency Division-Duplex, FDD) communication in accordance with an exemplary embodiment of the present invention. Port 2 of the quadrature circulator 810 is connected to an antenna. Port 3 of the quadrature circulator 810 is connected to the output of the reflection SIC amplifier 820. Port 3 is totally reflective and serves as a SIC input that directs its full power to RX port 4 to eliminate TX leakage. In TX mode, port 1 is at frequency f ₁ All TX power is transmitted to the antenna. In RX mode, the frequency f input from the antenna ₂ All power of the signal of (a) is reflected at port 3 and directed to port 4. Injection of cancellation port 4 frequency f from port 3 ₁ SIC signal of (A) is provided.

IV.4. RF front of multiple-input and multiple-output (MIMO) communication End of the device

Referring now to fig. 9, fig. 9 is a schematic block diagram of an RF front end for MIMO communication according to an exemplary embodiment of the present invention. RFFE 900 is suitable for MIMO architecture operating in half duplex, synchronous transmit-receive FDD and FD modes.

In FDD and FD, no RF coupling between the different antennas is required to eliminate mutual TX leakage, as all SIC functions can be concentrated in port 4. The SIC signal cancels all the leakage of the adjacent MIMO antennas and transmitters.

IV.5. RF front-end for carrier aggregation (Carrier Aggregation, CA) communication

Referring now to fig. 10, fig. 10 is a schematic block diagram of an RF front end for carrier aggregation communication according to an exemplary embodiment of the present invention. RFFE 1000 is suitable for CA architecture. Carrier frequency f ₁ RF transmit signal TX of (1) ₁ Input to reflective PA ₁ 1020. Carrier frequency f ₂ RF transmit signal TX of (1) ₂ Input at port 4 of circulator 1010. The aggregate signal is output to the antenna of port 2.

IV.6. multiple RF front ends for carrier aggregation (Carrier Aggregation, CA) communication

Referring now to fig. 11, fig. 11 is a schematic block diagram of an RF front-end for carrier aggregation communication and concurrent full duplex operation in accordance with a first exemplary embodiment. RFFE 1100 is also applicable to HD and STR/FDD communication modes as well as MIMO systems.

To support simultaneous transmit-receive for CA FD communication, RFFE 1100 includes two orthogonal circulators 1110 and 1130. Port 2 of the quadrature circulator 1130 is connected to port 4 of the quadrature circulator 1110.

Carrier frequency f ₁ RF transmit signal TX of (1) ₁ By reflecting PA ₁ 1120 are input to port 1 of the quadrature circulator 1110. Carrier frequency f ₂ RF transmit signal TX of (1) ₂ To port 1 of the quadrature circulator 1130. The quadrature circulator 1130 also inputs the SIC signal at port 3 and outputs the RX signal at port 4. The aggregate signal is output to the antenna of port 2 of the quadrature circulator 1100.

RFFE 1100 has simultaneous transmit/receive operation for port 4 of quadrature circulator 1110, and thus supports CA FD communication.

RFFE 1100 includes a second reflected power amplifier 1140 for delivering the SIC signal to port 3.

Referring now to fig. 12, fig. 12 is a schematic block diagram of an RF front-end for carrier aggregation communication and concurrent full duplex operation in accordance with a second exemplary embodiment of the present invention. RFFE 1200 is also suitable for operation in HD and STR/FDD modes and for MIMO communications.

To support simultaneous transmit-receive for CA FD communication, RFFE 1200 includes QBPA 1230.

Carrier frequency f ₁ RF transmit signal TX of (1) ₁ Input to reflective PA ₁ 1220.QBPA 1230 provides port 4 of circulator 1210 with a carrier frequency f ₂ Is combined with the SIC signal and the RF transmit signal TX ₂ . The aggregate signal is output to the antenna of port 2 of the quadrature circulator 1210.

The RX output of QBPA 1230 may perform simultaneous transmit/receive operations on port 4 of quadrature circulator 1210, thus supporting CA FD communication.

RFFE 1100 includes a second reflected power amplifier 1240 for delivering the SIC signal to port 3.

The embodiment of the invention cascades the quasi-circulator and the quadrature mixer to obtain the ideal quadrature circulator which is completely transmitted and has no power loss between continuous ports. The orthogonal circulator has smaller overall dimensions and on-chip integration compatibility. The quadrature circulator may be integrated into an RF front end suitable for many system architectures and RF communication modes.

The description of the various embodiments is for illustrative purposes only and is not intended to be exhaustive or limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles of the embodiments, the practical application, or the technological advancement of the art, or to enable others of ordinary skill in the art to understand the embodiments disclosed herein, as opposed to commercially available technology.

It is expected that during the life of this application many relevant quadrature hybrid, RF front-end, reflective amplifier, power amplifier, antenna, self-interference cancellation signal and electronic and opto-electronic device fabrication techniques will be developed and the scope of the terms quadrature hybrid, RF front-end, reflective amplifier, power amplifier, antenna, self-interference cancellation and quasi-circulator is intended to include all of these new techniques a priori.

The term "about" as used herein means ± 10%.

The terms "including," having, "and variations thereof mean" including but not limited to. This term includes the term "consisting of … …" as well as "consisting essentially of … …".

The phrase "consisting essentially of … …" means that a composition or method can include additional ingredients and/or steps provided that the additional ingredients and/or steps do not materially alter the basic and novel characteristics of the claimed composition or method.

As used herein, the singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise. For example, the term "a complex" or "at least one complex" may include a plurality of complexes, including mixtures thereof.

The word "exemplary" is used herein to mean "serving as an example, instance, or illustration. Any embodiment described as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments, and/or as excluding combinations of features of other embodiments.

The word "optionally" as used herein means "provided in some embodiments and not provided in other embodiments. Any particular embodiment may include multiple "optional" features unless these features conflict.

In this application, various embodiments may be presented in a range format. It should be understood that the description of the range format is merely for convenience and brevity and should not be construed as a fixed limitation on the scope of the embodiments. Accordingly, the description of a range should be considered to have specifically disclosed all possible sub-ranges as well as individual values within the range. For example, descriptions of ranges such as from 1 to 6 should be considered as having specifically disclosed sub-ranges from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as individual numbers within that range, such as 1, 2, 3, 4, 5, and 6. This applies regardless of the breadth of the range.

When a range of numbers is indicated herein, the representation includes any recited number (fractional or integer) within the indicated range. The phrases "a range between a first indicated number and a second indicated number" and "a range from a first indicated number to a second indicated number" are used interchangeably herein to mean that all fractions and integers between the first indicated number and the second indicated number are included.

It is appreciated that certain features of the embodiments, which are, for brevity, described in the context of a single embodiment, may also be provided in a single embodiment. Conversely, various features of the embodiments, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable subcombination or as appropriate in any other described embodiment. Certain features described in the context of various embodiments are not to be considered as essential features of such embodiments unless the embodiments are not operable without such elements.

While embodiments have been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims.

It is the applicant's intention that all publications, patents and patent applications mentioned in this specification are herein incorporated in their entirety by reference into the specification, to the same extent as if each individual publication, patent or patent application was specifically and individually indicated to be incorporated herein by reference. Furthermore, citation or identification of any reference in this application shall not be construed as an admission that such reference is available as prior art to the present invention. With respect to the use of section titles, the section titles should not be construed as necessarily limiting. In addition, the entire contents of any one or more priority files of the present application are incorporated by reference into the present application.

Claims

1. A quadrature circulator device, comprising:

quasi-circulator (100), comprising:

-a first port (101), a second port (102), a third port (103) and a fourth port (104), wherein the scattering matrix S1 of the quasi-circulator (100) is represented as:

wherein each element S1 in the scattering matrix S1 _xy Representing a portion of the square root of the power of the signal directed by the quasi-circulator (100) from the y-th port to the x-th port, where x and y may be 1, 2, 3 and 4 and x is not equal to y, each element S1 _xx A portion representing the square root of the power of the signal reflected at the x-th port;

quadrature mixer (150) comprising a first port (151), a second port (152), a third port (153) and a fourth port (154), wherein a scattering matrix S2 of the quadrature mixer (150) is represented as:

wherein each element S2 in the scattering matrix S2 _xy Representing a portion of the square root of the power of the signal directed by the quadrature mixer (150) from the y-th port to the x-th port, where x and y can be 1, 2, 3 and 4 and x is not equal to y, each element S2 _xx A portion representing the square root of the power of the signal reflected at the x-th port,

the fourth port of the quasi-circulator (104) is connected to the fourth port of the quadrature mixer (154), and the third port of the quasi-circulator (103) is connected to the first port of the quadrature mixer (151).

2. The orthogonal circulator device according to claim 1, wherein the quasi-circulator (400) comprises:

a first 90 degree reciprocal phase shifter (reciprocal phase shifter, RPS) (405) between the first port (401) of the quasi-circulator and the second port (402) of the quasi-circulator;

-a second 90 degree RPS (406) between the second port (402) of the quasi-circulator and the third port (403) of the quasi-circulator;

a 90 degree non-reciprocal phase shifter (non-reciprocal phase shifter, NRPS) (407) between the third port (403) of the quasi-circulator and the fourth port (404) of the quasi-circulator;

a third 90 degree RPS (408) between the fourth port (404) of the quasi-circulator and the first port (401) of the quasi-circulator,

wherein the characteristic impedance of the first RPS (405) is a first value equal to the impedance of the first port (401) of the quasi-circulator, the characteristic impedance of the second RPS (406) and the third RPS (408) is a second value, wherein the second value is equal to the first value divided by

3. The orthogonal quasi-circulator device (100) of claim 2, wherein the NRPS (407) is impedance transparent.

4. A quadrature quasi-circulator device according to any one of claims 1 to 3, characterized in that the phase of the forward signal path from the first port (101) of the quasi-circulator through the second port (102) of the quasi-circulator to the third port (103) of the quasi-circulator is 180 degrees and the phase of the forward signal path from the first port (101) of the quasi-circulator through the fourth port (104) of the quasi-circulator to the third port (103) of the quasi-circulator is 0 degrees.

5. The orthogonal quasi-circulator device (100) of any of claims 1 to 4, further comprising an antenna connected to the second port of the quasi-circulator (102).

6. The quadrature quasi-circulator device (100) of any one of claims 1 to 5, further comprising a first reflective element, wherein an output of the first reflective element is connected to the third port of the quadrature mixer (153).

7. The orthogonal quasi-circulator device (100) of any of claims 1 to 6, further comprising a second reflective element, wherein an output of the second reflective element is connected to the first port of the quasi-circulator (101).

8. A method for operating the orthogonal circulator device of claim 1, comprising:

inputting a first Radio Frequency (RF) signal into one of the first port of the quasi-circulator (101), the second port of the quasi-circulator (102), the second port of the quadrature mixer (152), and the third port of the quadrature mixer (153);

a second Radio Frequency (RF) signal is output from one of the first port of the quasi-circulator (101), the second port of the quasi-circulator (102), the second port of the quadrature mixer (152), and the third port of the quadrature mixer (153).

9. A method for operating the orthogonal circulator device of claim 8, comprising:

-inputting a transmit signal at the first port of the quasi-circulator (101);

inputting a signal received from an antenna connected to the second port of the quasi-circulator (102), and outputting the transmission signal to the antenna;

-inputting a self-interference cancellation (self-interference cancellation, SIC) signal at the third port of the quadrature mixer (153) by means of a reflective element (620);

the received signal is output from the second port of the quadrature hybrid (152).

10. A method for operating the orthogonal circulator device of claim 8, comprising:

-inputting a transmit signal at the first port of the quasi-circulator (101);

-reflecting the received signal at the third port of the quadrature mixer (153) by a reflecting element (720) connected to the third port of the quadrature mixer (153);

11. A method for operating the orthogonal circulator device of claim 8, comprising:

inputting a transmit signal in a first frequency band at the first port of the quasi-circulator (101);

inputting a signal in a second frequency band received from an antenna connected to the second port of the quasi-circulator (102), and outputting the transmission signal to the antenna;

-inputting a self-interference cancellation (self-interference cancellation, SIC) signal at the third port of the quadrature mixer (153) by means of a reflective element (820);

12. A method for operating the orthogonal circulator device of claim 8, comprising:

-inputting a first transmission signal in a first frequency band at said first port of said quasi-circulator (101) by means of a reflecting element (1020);

inputting a second transmit signal in a second frequency band at the second port of the quadrature hybrid (152);

the first transmit signal and the second transmit signal are output from the second port of the quasi-circulator (102).