System and method for measuring radio frequency phase shift of inline device
By using a variable gain amplifier, a variable feedback block, and an adjustable phase shifter in the oscillator circuit to adjust the phase and gain to meet the Barkhausen condition, the problem of phase shift measurement and compensation for inline devices was solved, ensuring the accuracy of the phase relationship of electronic equipment.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-25
- Publication Date
- 2026-04-10
AI Technical Summary
Existing technologies struggle to accurately measure and compensate for phase shifts introduced by inline devices, which affect the phase relationships of electronic devices.
By using a variable gain amplifier and a variable feedback block in the oscillator circuit, combined with an adjustable phase shifter and a processor, the phase and gain are adjusted to meet the Barkhausen phase condition, thus determining and compensating for the phase shift of the inline device.
It enables rapid and accurate measurement and compensation of phase shifts introduced by inline devices, ensuring the accuracy of phase relationships in electronic devices.
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Figure CN121841284A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The subject disclosure relates to inline devices, and in particular to systems and methods for measuring a phase shift of an inline device and compensating for a phase shift introduced by the inline device. BACKGROUND
[0002] Various electronic devices, such as beamforming devices, require precise phase relationships to operate correctly. Additional phase shifts can be introduced into the signal path through repeated installation of the apparatus, temperature variations, various mechanical conditions, etc., all of which need to be accounted for in order to maintain the desired phase relationships. Accordingly, it is desirable to provide a system and method for measuring a phase shift caused by the insertion of an inline device and compensating for the phase shift. SUMMARY
[0003] In one example embodiment, a method for determining a phase shift of an inline device is disclosed. The inline device is installed in an oscillator circuit that includes a loop having a variable gain amplifier and a variable feedback block. The inline device is installed between the variable gain amplifier and the variable feedback block. An output of the variable feedback block is input to the variable gain amplifier. A phase of the variable feedback block is changed to locate a block phase shift of the variable feedback block at which the oscillator circuit generates an output signal. A device phase shift of the inline device is determined from the block phase shift. An operation of a driven device that operates in accordance with the output of the oscillator circuit is adjusted using the device phase shift of the inline device.
[0004] In addition to one or more features described herein, locating the block phase shift includes changing the phase of the variable feedback block and a gain of the amplifier until the loop satisfies a Barkhausen phase condition.
[0005] In addition to one or more features described herein, the method further includes determining a first block phase shift of the variable feedback block that satisfies the Barkhausen phase condition without the inline device, introducing the inline device in the loop, determining a second block phase shift of the loop with the inline device that satisfies the Barkhausen phase condition, and determining the device phase shift of the inline device from a difference of the first block phase shift and the second block phase shift.
[0006] In addition to one or more features described herein, wherein the variable feedback block includes a tunable phase shifter, the method further includes changing a phase of the tunable phase shifter to locate the block phase shift.
[0007] In addition to one or more features described herein, the tunable phase shifter is one of a mechanically tunable phase shifter, an electrically tunable phase shifter, a varactor diode, and a time delay device.
[0008] In addition to one or more of the features described herein, the method includes increasing a gain of the variable gain amplifier to operate the oscillator circuit in a saturated state to produce a square wave, and adjusting a phase of the variable feedback block to position a block phase shift with the oscillator circuit in the saturated state.
[0009] In addition to one or more of the features described herein, the method includes using an output of the oscillator circuit in at least one of a beamforming circuit, a radar circuit, and a cellular network.
[0010] In another example embodiment, an oscillator circuit is disclosed. The oscillator includes a variable gain amplifier, a variable feedback block, an inline device, and a processor. The inline device is installed between the variable gain amplifier and the variable feedback block to form a loop. An output of the variable feedback block is input to the variable gain amplifier. The processor is configured to change a phase of the variable feedback block to position a block phase shift of the variable feedback block at which the oscillator circuit generates an output signal, determine a device phase shift of the inline device from the block phase shift, and adjust an operation of a driven circuit operating from the output of the oscillator circuit using the device phase shift of the inline device.
[0011] In addition to one or more of the features described herein, the processor is further configured to position the block phase shift by changing the phase of the variable feedback block until the loop satisfies a Barkhausen phase condition.
[0012] In addition to one or more of the features described herein, the processor is further configured to determine a first block phase shift of the variable feedback block that satisfies a Barkhausen phase condition without the inline device, determine a second block phase shift that satisfies the Barkhausen phase condition of the loop with the inline device inserted in the loop, and determine the device phase shift of the inline device from a difference of the first block phase shift and the second block phase shift.
[0013] In addition to one or more of the features described herein, wherein the variable feedback block includes a tunable phase shifter, the processor is further configured to change a phase of the tunable phase shifter to position the block phase shift.
[0014] In addition to one or more of the features described herein, the tunable phase shifter is one of a mechanically tunable phase shifter, an electrically tunable phase shifter, a varactor diode, and a time delay device.
[0015] In addition to one or more of the features described herein, the processor is further configured to increase a gain of the variable gain amplifier to operate the oscillator circuit in a saturated state to produce a square wave, and adjust a phase of the variable feedback block to position a block phase shift with the oscillator circuit in the saturated state.
[0016] In addition to one or more of the features described herein, the output is sent to at least one of a beamforming circuit, a radar circuit, and a cellular network.
[0017] In another example embodiment, a test apparatus is disclosed. The test apparatus includes an oscillator circuit and a processor. The oscillator circuit includes a variable gain amplifier and a variable feedback block, wherein an inline device is installed between the variable gain amplifier and the variable feedback block to form a loop, and an output of the variable feedback block is input to the variable gain amplifier. The processor is configured to change a phase of the variable feedback block to locate a block phase shift of the variable feedback block at which the oscillator circuit generates an output signal, determine a device phase shift of the inline device from the block phase shift, and adjust an operation of a driven circuit operating in accordance with the output of the oscillator circuit using the device phase shift of the inline device.
[0018] In addition to one or more of the features described herein, the processor is further configured to locate the block phase shift by changing the phase of the variable feedback block until the loop satisfies a Barkhausen phase condition.
[0019] In addition to one or more of the features described herein, the processor is further configured to determine a first block phase shift of the variable feedback block that satisfies a Barkhausen phase condition without the inline device, determine a second block phase shift that satisfies the Barkhausen phase condition of the loop with the inline device inserted in the loop, and determine the device phase shift of the inline device from a difference between the first block phase shift and the second block phase shift.
[0020] In addition to one or more of the features described herein, wherein the variable feedback block includes a tunable phase shifter, the processor is further configured to change a phase of the tunable phase shifter to locate the block phase shift.
[0021] In addition to one or more of the features described herein, the tunable phase shifter is one of a mechanically tunable phase shifter, an electrically tunable phase shifter, a varactor diode, and a time delay device.
[0022] In addition to one or more of the features described herein, the processor is further configured to increase a gain of the variable gain amplifier to operate the oscillator circuit in a saturated state to produce a square wave, and adjust the phase of the variable feedback block to locate the block phase shift with the oscillator circuit in the saturated state.
[0023] The above features and advantages of the present disclosure, and other features and advantages, are readily apparent from the following detailed description when taken in connection with the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS
[0024] Other features, aspects, and details are described in only examples, with additional aspects described in the following detailed description and illustrated in the accompanying drawings. As will be apparent to those of ordinary skill in the art, features, aspects, and
[0025] Figure 1 A circuit according to an example embodiment is shown;
[0026] Figure 2 A diagram of an oscillator circuit in an alternative embodiment is shown;
[0027] Figure 3 A modified oscillator circuit in an illustrative embodiment is shown;
[0028] Figure 4 A gain / phase space of a loop is shown; and
[0029] Figure 5 A flowchart of a method for searching a gain / phase space by searching only the phase parameter is shown. DETAILED DESCRIPTION
[0030] The following description is merely exemplary in nature and is not intended to limit the present disclosure, its application or uses. It should be understood that throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features.
[0031] According to an example embodiment, Figure 1 A circuit 100 is shown. The circuit 100 includes an oscillator circuit 102 and a driven device or driven circuit 104. The output of the oscillator circuit 102 is provided to the driven circuit 104. The driven circuit 104 can be a beamforming circuit, a radar circuit, a cellular network, or other suitable electrical device that can operate from an oscillator signal input.
[0032] The oscillator circuit 102 includes an amplifier 106, such as an operational amplifier, and a feedback network 108. The amplifier 106 is labeled A and the feedback network 108 is labeled B. The output of the amplifier 106 is fed to the input of the feedback network 108 and the output of the feedback network is fed to the input of the amplifier.
[0033] For oscillation to occur, the feedback circuit must satisfy the Barkhausen conditions at some frequency. The Barkhausen conditions include: 1) the total loop gain is 1, and 2) the total loop phase shift is a multiple of 360 degrees (2π). The first Barkhausen condition (the Barkhausen gain condition) is shown as (Equation (1)):
[0034] |A|*|B|=1 Equation (1)
[0035] where |A| is the magnitude of the amplifier gain and |B| is the magnitude of the feedback network gain. The second Barkhausen condition (the Barkhausen phase condition) is shown as Equation (2):
[0036] ang(A) + ang(B) = k*2π Equation (2)
[0037] where ang(A) is the phase of the amplifier, ang(B) is the phase of the feedback network, and k is an integer. Typically, the amplifier gain |A| is a constant value and the amplifier phase shift ang(A) is a constant value. Similarly, the feedback network gain |B| is a constant value and the feedback network phase shift ang(B) is a constant value.
[0038] Figure 2 A diagram 200 of the oscillator circuit 102 in an alternative embodiment is shown. The oscillator circuit 102 includes the amplifier 106, the feedback network 108, and an inline device 202. The inline device 202 can be a wire, a filter, a transmission line, or other suitable device. The output of the amplifier 106 is fed into the inline device 202. The output of the inline device 202 is fed into the feedback network 108, and the output of the feedback network is fed into the input of the amplifier 106.
[0039] The inclusion of the inline device 202 in the loop changes the gain and phase of the loop. Figure 2 The Barkhausen condition for the oscillator circuit 102 is shown in equations (3) and (4):
[0040] |A| * |B| * |C| = 1 equation (3)
[0041] where |C| is the magnitude of the inline device.
[0042] ang(A) + ang(B) + ang(C) = k * 2π equation (4)
[0043] where ang(C) is the phase of the inline device. By compensating for the changes in gain and phase due to the introduction of the inline device 202 into the loop, the additional device phase shift introduced by the inline device can be determined.
[0044] Figure 3 A modified oscillator circuit 300 in an illustrative embodiment is shown. The modified oscillator circuit 300 can be used as part of a test device for testing the device phase shift introduced by an inline device. The modified oscillator circuit 300 includes a variable gain amplifier 302 and a variable feedback block 304. The variable feedback block 304 is indicated by B' and includes the feedback network 108, the inline device 202, and a tunable phase shifter 306.
[0045] The controller 308 controls the operation of the variable gain amplifier 302 and the adjustable phase shifter 306. The controller 308 can include processing circuitry, which can include an application specific integrated circuit (ASIC), an electronic circuit, a processor (shared, dedicated, or group) and memory that execute one or more software or firmware programs, a combinational logic circuit, and / or other suitable components that provide the described functionality. The controller 308 can include a non-transitory computer-readable medium storing instructions that, when processed by one or more processors of the controller 308, implement a method of determining a device phase shift of the inline device 202 in accordance with one or more embodiments detailed herein.
[0046] The gain |A| of the variable gain amplifier 302 can be raised or lowered. Both the gain and the phase shift of the adjustable phase shifter 306 can be adjusted. As a non-limiting example, the adjustable phase shifter 306 can be a mechanically adjustable phase shifter, an electrically adjustable phase shifter (e.g., or a mechanically phase shifter adjusted by a motor), a varactor diode or a device based on one or more varactor diodes, a time delay device or a device with multiple time delay sections, etc. In an embodiment, the output of the inline device 202 is fed to the adjustable phase shifter 306. The feedback network 108 and the adjustable phase shifter 306 are connected in series.
[0047] Since the device phase shift of the inline device 202 is most likely not zero (i.e., ang(C)≠ 0), the adjustable phase shifter 306 can be operated to make Figure 3 the loop satisfy the Barkhausen phase condition. Once the block phase shift of the variable feedback block 304 (and the gain of the variable gain amplifier 302), ang(B' ) is found to satisfy the Barkhausen phase condition, ang(A) + ang(B') = k*2p, the device phase shift introduced by the inline device 202, ang(C) can be extracted. This is shown by equation (4):
[0048] ang(C) = ang(B') - ang(B) equation (4)
[0049] To determine the Barkhausen condition, the gain and the phase of the loop need to be adjusted until these conditions are satisfied. This amounts to searching the phase space of the loop circuit again.
[0050] A separate measurement can be used to determine the device phase shift of the inline device. A first block phase shift of the variable feedback block that satisfies the Barkhausen phase condition without the inline device 202 in the loop is determined. The inline device 202 is then introduced into the loop. A second block phase shift of the variable feedback block is determined that satisfies the Barkhausen phase condition for the loop including the inline device 202. The gain of the variable feedback block can be adjusted prior to determining the second block phase shift. The device phase shift of the inline device 202 is determined from the difference between the first block phase shift and the second block phase shift.
[0051] Figure 4 The gain / phase space 400 of the loop is shown. A gain axis (G) and a phase axis (ϕ) are shown. An amplitude axis (A) indicates the strength of the oscillating signal and / or whether the oscillation is decaying or exploding. A first region 402 is defined in the space where the gain and phase satisfy the Barkhausen condition. A second region 404 is defined where the gain and phase do not satisfy the Barkhausen condition. When both Barkhausen conditions are satisfied by the loop, oscillation exists in the improved oscillator circuit 300, but when either of these conditions is not satisfied, oscillation generally does not exist. The boundary 406 between the first region 402 and the second region 404 is sharp. Thus, when searching the gain / phase space, oscillation quickly appears (as shown by the extension of the boundary along the amplitude axis when the Barkhausen condition is satisfied (i.e., in the first region 402)) and quickly disappears when the condition is not satisfied (i.e., in the second region 404).
[0052] The tunable phase shifter 306 generally has an insertion loss that results in a gain relationship between the input signal and the output signal. This insertion loss can be independently measured and stored. When the tunable phase shifter 306 is added to the loop, the stored data can be pulled out and used as an initial value in performing a search of the gain of the loop.
[0053] The insertion loss of the inline device 202 is generally unknown. Thus, when the inline device 202 is introduced into the loop, a search algorithm can be performed to determine a value of the gain |A| of the variable gain amplifier 302 that compensates for the insertion loss of the inline device 202 such that the loop satisfies the Barkhausen gain condition.
[0054] While a two-dimensional search of the gain / phase space can be performed to locate the Barkhausen condition, due to the sharpness of the boundary 406 between the first region 402 and the second region 404, such a two-dimensional search can be a time-consuming process. Thus, it is desirable to search the gain / phase space in a manner that can be completed in a reduced amount of time.
[0055] Figure 5A flowchart 500 showing a method for searching the gain / phase space by searching only the phase parameter is shown. In block 502, an inline device is inserted into an oscillator circuit, which includes a variable gain amplifier 302 and a tunable phase shifter 306. In block 504, the gain of the variable gain amplifier 302 is raised to a value that causes the oscillator circuit to produce saturation. In this saturated state, the variable gain amplifier 302 produces a square wave instead of a sine wave. Since the square wave includes multiple harmonic frequencies (not just the fundamental frequency), the search can be performed by changing only the phase parameter. In block 506, a one-dimensional search of the phase parameter can be performed to locate a phase that satisfies the Barkhausen condition for the loop. This one-dimensional search can be performed in a reduced amount of time compared to a two-dimensional search of the gain / phase space. In block 508, the gain of the tunable phase shifter is determined that causes the loop to satisfy the Barkhausen gain condition for the located phase.
[0056] The terms "a" and "an" do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced item. The term "or" means "and / or" unless clearly indicated otherwise. References throughout this specification to "aspects" mean that a particular element described can be included in the at least one aspect, and can or can not be present in other aspects. Furthermore, it is to be understood that the described elements can be combined in any suitable manner in the various aspects.
[0057] When an element such as a layer, film, region, or substrate is referred to as being "on" another element, it can be directly on the other element or intervening elements can also be present. In contrast, when an element is referred to as being "directly on" another element, there are no intervening elements present.
[0058] Unless specifically stated otherwise, all test standards are the most recent standard as of the filing date of this application, or, if priority is claimed, the most recent standard as of the filing date of the earliest priority application in which the test standard appears.
[0059] Unless defined otherwise, technical and scientific terms used herein have the same meaning as is commonly understood by one of skill in the art to which this disclosure belongs.
[0060] While the foregoing disclosure has described exemplary embodiments, one of ordinary skill in the art will understand that various changes can be made therein without departing from the scope of the disclosure. For example, various elements of the disclosed embodiments can be combined, substituted, or deleted, and the material of the disclosure can be adapted in a manner that is not a departure from the spirit and scope of the disclosure. Further, many modifications can be made to adapt a particular situation or material to the teachings of the disclosure without departing from the central scope of the disclosure. Therefore, it is intended that the disclosure not be limited to the particular embodiment disclosed as the scope of the disclosure will be defined by the appended claims.
Claims
1. A method for determining the phase shift of an inline device, comprising: The inline device is installed in an oscillator circuit, the oscillator circuit including a loop with a variable gain amplifier and a variable feedback block, wherein the inline device is installed between the variable gain amplifier and the variable feedback block, wherein the output of the variable feedback block is input to the variable gain amplifier; The phase of the variable feedback block is changed to locate the block phase shift of the variable feedback block, and the oscillator circuit generates an output signal at the block phase shift. The device phase shift of the inline device is determined based on the block phase shift. and The device phase shift of the inline device is used to adjust the operation of the driven device according to the output operation of the oscillator circuit.
2. The method according to claim 1, wherein, Positioning the block phase shift also includes changing the phase of the variable feedback block and the gain of the variable gain amplifier until the loop satisfies the Barkhausen phase condition.
3. The method according to claim 2, further comprising: The process involves determining the first block phase shift of the variable feedback block that satisfies the Barkhausen phase condition in the absence of the inline device, introducing the inline device into the loop, determining the second block phase shift of the loop with the inline device that satisfies the Barkhausen phase condition, and determining the device phase shift of the inline device based on the difference between the first block phase shift and the second block phase shift.
4. The method of claim 1, wherein the variable feedback block includes an adjustable phase shifter, and further includes changing the phase of the adjustable phase shifter to position the block phase shift.
5. The method of claim 1, further comprising increasing the gain of the variable gain amplifier to operate the oscillator circuit in a saturated state to generate a square wave, and adjusting the phase of the variable feedback block to position the block phase shift when the oscillator circuit is in a saturated state.
6. An oscillator circuit, comprising: Variable gain amplifier; Variable feedback block; An inline device installed between the variable gain amplifier and the variable feedback block to form a loop, wherein the output of the variable feedback block is input to the variable gain amplifier; and Processor, the processor being configured to: The phase of the variable feedback block is changed to locate the block phase shift of the variable feedback block, and the oscillator circuit generates an output signal at the block phase shift. The device phase shift of the inline device is determined based on the block phase shift. and The device phase shift of the inline device is used to adjust the operation of the driven circuit according to the output operation of the oscillator circuit.
7. The oscillator circuit according to claim 6, wherein, The processor is also configured to locate the block phase shift by changing the phase of the variable feedback block until the loop satisfies the Barkhausen phase condition.
8. The oscillator circuit according to claim 7, wherein, The processor is also configured to determine a first block phase shift of the variable feedback block that satisfies the Barkhausen phase condition in the absence of the inline device, to determine a second block phase shift of the loop that satisfies the Barkhausen phase condition when the inline device is inserted into the loop, and to determine the device phase shift of the inline device based on the difference between the first block phase shift and the second block phase shift.
9. The oscillator circuit of claim 6, wherein the variable feedback block includes an adjustable phase shifter, and the processor is further configured to change the phase of the adjustable phase shifter to position the block phase shift.
10. The oscillator circuit according to claim 6, wherein, The processor is also configured to increase the gain of the variable gain amplifier to operate the oscillator circuit in a saturated state to generate a square wave, and to adjust the phase of the variable feedback block to position the block phase shift when the oscillator circuit is in a saturated state.