Airborne measurement system

Abstract

An over-the-air measurement system for testing a device under test is provided. The over-the-air measurement system includes at least two quadrature modulators and at least two antennas. Each of the antennas is connected to a dedicated quadrature modulator, thereby establishing at least two measurement modules. The at least two quadrature modulators are rotated with respect to each other, thereby providing different measurement polarizations of the at least two measurement modules with respect to a common reference plane.

Description

Technical Field

[0001] This invention relates to an aerial measurement system for testing equipment under test. Background Technology

[0002] In the prior art, over-the-air (OTA) measurement systems for testing devices under test (DUTs) are well known. Typically, a so-called compact antenna test range (CATR) is used to test the corresponding DUT, which has a test chamber, such as an anechoic chamber, also known as an RF shielded chamber, in which the DUT is placed for testing purposes. The measurement system provides a quiet zone within the test chamber, which is associated with the test location where the DUT is placed during testing. In the compact antenna test range, at least one reflector can be used to establish a beam path between the test location and the corresponding feed antenna (also known as the measurement antenna) to increase the propagation distance of electromagnetic waves, thereby ensuring (indirect) far-field (IFF) conditions at the test location located within the quiet zone.

[0003] The corresponding device under test (DUT) typically includes a dual-polarized antenna, making it necessary to perform at least four measurements with four different measurement polarizations in order to measure the axial ratio and maximum power of the DUT. For example, the DUT uses dual-polarized electromagnetic waves. Therefore, the DUT can involve FR1 base stations and / or FR2 base stations, FR2 user equipment, and radar equipment.

[0004] In the prior art, it is well known that in order to test four different measurement polarizations, two separately formed feed antennas and a mechanical feed switch that mechanically moves the feed antennas are used.

[0005] In other words, the feed antenna is mechanically altered, i.e., moved, which increases the overall cost of the aerial measurement system. Furthermore, the total measurement time is relatively long due to the fact that measurements must be interrupted when the feed antenna is moved.

[0006] Therefore, a cost-effective way to perform the corresponding tests is needed. Summary of the Invention

[0007] This invention provides an aerial measurement system for testing a device under test (DUT). The aerial measurement system includes at least two orthogonal mode converters (GMs) and at least two antennas. Each of the antennas is connected to a dedicated GM, thereby establishing at least two measurement modules. The at least two GMs are rotated relative to each other, thereby providing different measurement polarizations for the at least two measurement modules relative to a common reference plane.

[0008] The main idea of ​​this invention is that at least two measurement modules with orthogonal mode converters are rotated relative to each other, such that when testing the device under test, the two orthogonal mode converters simultaneously provide different measurement polarizations due to their relative rotation. In other words, the orthogonal mode converters are positioned relative to each other such that the corresponding polarization reference plane associated with one of the orthogonal mode converters is skewed relative to the other due to the relative rotation.

[0009] Typically, at least two measurement modules are rotated relative to each other, causing the polarization of their antennas to tilt accordingly, particularly relative to a common reference plane.

[0010] Since at least two measurement modules are fixedly arranged, for example, they will not move relative to each other during testing, an orthogonal mode converter assembly is provided.

[0011] The orthogonal mode converter assembly includes at least two measurement modules that are stationary, or more precisely, static, during the testing of the device under test.

[0012] Therefore, different measurement polarizations are obtained due to the corresponding (static) arrangement of at least two measurement modules relative to each other, rather than due to the movement of at least two measurement modules relative to each other.

[0013] On the one hand, it is stipulated that each of the at least two antennas is a dual-polarized antenna. Therefore, each dual-polarized antenna simultaneously provides two different measurement polarizations. Due to the relative rotation of the orthogonal mode converters relative to each other, the two different measurement polarizations of each antenna are offset relative to each other.

[0014] Specifically, at least two antennas together provide a total of four different measurement polarizations. Since each of the at least two antennas provides two different measurement polarizations, and both antennas rotate relative to each other, four different measurement polarizations are obtained. These different measurement polarizations are required to properly test dual-polarized devices under test (DUTs), particularly dual-polarized antennas under test, or more precisely, DUTs with one or more dual-polarized antennas.

[0015] On the other hand, it is specified that at least two orthogonal mode converters are arranged relative to each other such that the different measurement polarizations are offset from each other by 45° relative to a common reference plane. Accordingly, the corresponding polarization reference plane of at least one orthogonal mode converter is skewed by 45° relative to another orthogonal mode converter, which may be parallel to the common reference plane (e.g., a horizontal plane).

[0016] Therefore, both dual-polarized antennas provide polarization at 0° and 90° (first dual-polarized antenna) and polarization at -45° and +45° (second dual-polarized antenna). Thus, four different measurement polarizations are simultaneously provided. In other words, four different measurement polarizations can be obtained without moving, or more precisely, rotating, an antenna or, more precisely, an orthogonal mode converter, as their specific static arrangement already ensures four different measurement polarizations.

[0017] Accordingly, measurement time can be significantly reduced because there is no need to move or, more precisely, rotate the components during testing to ensure that the device under test is tested with at least four different measurement polarizations.

[0018] On the other hand, it is stipulated that the number of antennas equals the number of quadrature mode converters (QMTs). In practice, each QMT is connected to a dedicated antenna (e.g., a measurement antenna, also known as a feed antenna). Each QMT is connected to a dedicated output interface and two input interfaces, through which it receives orthogonally polarized signals of different polarizations, such as horizontally polarized signals and vertically polarized signals.

[0019] Furthermore, at least two orthogonal mode converters and / or at least two antennas and / or at least two measurement modules are constructed identically. Therefore, the corresponding components of the orthogonal mode converter assembly are similar. Consequently, due to the relative rotational arrangement of the orthogonal mode converters, and particularly the relative rotational arrangement of the measurement modules, a corresponding additional measurement polarization is obtained individually. The relative rotational arrangement means that the corresponding components of the orthogonal mode converter assembly are stationary relative to each other, or more precisely, fixedly positioned, but their polarization reference planes are skewed relative to each other, or more precisely, tilted, for example, by 45°.

[0020] On the other hand, it is specified that the antenna phase center spacing is less than 2 cm. Therefore, it is not necessary to reposition the device under test during testing, because the displacement of the quiet zone is minimized when the antenna is changed for testing purposes. Accordingly, the measurement modules of the quadrature mode converter assembly are positioned relative to each other such that the output interfaces of the measurement modules to which the antennas are connected are close to each other, resulting in an antenna phase center spacing of less than 2 cm, particularly less than 1.8 cm, preferably (approximately) 1.6 cm.

[0021] Furthermore, the aerial measurement system includes at least one reflector. The reflector can be used to increase the propagation distance of electromagnetic waves along the beam path between one or more antennas and the device under test, thereby ensuring (indirect) far-field (IFF) conditions. Therefore, the device under test can be tested under real-world conditions, i.e., in the far-field condition.

[0022] At least two antennas can be located substantially at the focal point of at least one reflector. Because the phase centers of the two antennas are less than 2 cm apart, it can be ensured that both antennas are substantially located at the focal point of at least one reflector, thereby minimizing the shift of the quiet zone.

[0023] Furthermore, each of the at least two measurement modules may include a housing that accommodates a corresponding quadrature mode converter. The quadrature mode converter is located inside the corresponding housing to which the antenna is connected (particularly the output interface provided on the outside of the housing).

[0024] Each of at least two measurement modules may include two input ports and one output port, with a corresponding antenna connected to the output port. Each port provides a corresponding interface for interconnecting waveguides and / or antennas. Therefore, each port may be located on the outer surface of the respective housing, allowing easy connection of the corresponding one or more waveguides and / or one or more antennas to the corresponding measurement module.

[0025] In addition, RF shielded chambers can be provided. RF shielded chambers ensure that interference or disturbance signals are properly shielded, thereby improving test conditions and resulting in a more reliable characterization of the device under test.

[0026] Furthermore, the airborne measurement system includes measuring instruments. These instruments can provide corresponding signals of different polarizations, which are relayed to an orthogonal mode converter assembly, specifically its input port. Therefore, the measuring instruments may include signal generators, wherein the instruments are connected to corresponding waveguides, which are connected to the input port, such that the generated signals (i.e., signals of different polarizations) are relayed to the orthogonal mode converter assembly.

[0027] In addition, analytical instruments can be provided to connect to the orthogonal mode converter assembly and / or the device under test (DUT) to receive the signals to be analyzed in order to characterize the behavior of the DUT during testing.

[0028] In addition, a positioner system for the device under test (DUT) can be provided. The positioner system can be used to rotate the DUT during testing to fully characterize it, particularly in several directions. In practice, the positioner system can be a three-dimensional (3D) positioner system, such as a phone positioner and a tablet positioner in the case of testing mobile phones or tablets.

[0029] In summary, the locator system ensures accurate azimuth and elevation positioning of the device under test, especially in quiet areas.

[0030] In fact, total radiated power (TRP) measurements can be performed accurately and quickly.

[0031] Aerial measurement systems can be far-field systems. In fact, direct far-field conditions can be provided due to the guaranteed distance between one or more antennas and the device under test.

[0032] In other words, an airborne measurement system can be a compact antenna test range (CATR) system. A compact antenna test range system includes a reflector used to increase the propagation distance of electromagnetic signals, thereby ensuring (indirect) far-field conditions for testing the device under test under far-field conditions.

[0033] In summary, a compact multi-band quadrature mode converter (QMTC) assembly is provided, having two or more QMTCs (e.g., three QMTCs). An input interface associated with one QMTC provides different polarization signals, such as orthogonally polarized signals like horizontally polarized signals and vertically polarized signals. Each QMTC in the multi-band QMTC assembly can split a corresponding signal received via an output interface into two components orthogonally polarized relative to each other, wherein these components are forwarded to the input interface. Furthermore, each QMTC is also configured to combine the orthogonally polarized signals received via the input interface into a combined signal, which is forwarded to the output interface. Attached Figure Description

[0034] The foregoing aspects of the claimed subject matter, and the many advantages that follow, will become more readily apparent, as will the following detailed description, taken with reference to the accompanying drawings, in which:

[0035] - Figure 1 An overview of an aerial measurement system according to an embodiment of the present invention is schematically shown.

[0036] - Figure 2 An overview of an aerial measurement system according to another embodiment of the present invention is schematically shown.

[0037] - Figure 3 A schematic front view of an orthogonal mode converter assembly with two measurement modules is shown, and

[0038] - Figure 4 It shows Figure 3 An isometric view of the orthogonal mode converter assembly. Detailed Implementation

[0039] The detailed description set forth below in conjunction with the accompanying drawings is intended to describe various embodiments of the disclosed subject matter and is not intended to represent only embodiments, in which the same numerals refer to the same elements. Each embodiment described in this disclosure is provided only as an example or illustration and should not be construed as superior or better than other embodiments. The illustrative examples provided herein are not intended to be exhaustive or to limit the claimed subject matter to the precise forms disclosed.

[0040] For the purposes of this disclosure, for example, the phrase “at least one of A, B, and C” means (A), (B), (C), (A and B), (A and C), (B and C), or (A, B, and C), including all other possible permutations when listing more than three elements. In other words, “at least one of A and B” generally means “A and / or B”, that is, “A” alone, “B” alone, or “A and B”.

[0041] Figure 1 An aerial measurement system 10 for testing the device under test 12 is shown.

[0042] The airborne measurement system 10 includes an anechoic chamber, or more precisely an RF shielded chamber 14, which houses the device under test 12 and an orthomode transducer (OMT) assembly 16 for testing the device under test 12, which will be described in more detail below.

[0043] The aerial measurement system 10 also includes a positioner system 18 for the device under test 12, wherein the positioner system 18 can be configured to rotate the device under test 12 at least along one axis of rotation during testing, particularly in a three-dimensional manner, i.e., along at least two axes of rotation. The device under test 12 is mounted on the positioner system 18.

[0044] Furthermore, the aerial measurement system 10 includes a measuring instrument 20 and an analysis instrument 22, which are suitably connected to the orthogonal mode converter assembly 16 and / or the positioner system 18. Additionally, signals received by the device under test 12 can be forwarded to the analysis instrument 22, thus establishing a corresponding communication connection between the device under test 12 and the analysis instrument 22. Furthermore, the measuring instrument 20 can be connected to the device under test 12.

[0045] The corresponding connection between the measuring instrument 20 and the quadrature mode converter assembly 16 can be established by means of the waveguide that forwards different polarization signals to the quadrature mode converter assembly 16.

[0046] In addition, Figure 1 The diagram shows that the aerial measurement system 10 includes two reflectors 24, namely a primary reflector 26 and a secondary reflector 28. Accordingly, Figure 1 The aerial measurement system 10 shown is a multi-reflector system.

[0047] In the illustrated embodiment, the primary reflector 26 is configured as a parabolic reflector, while the secondary reflector 28 is configured as a non-parabolic reflector.

[0048] The primary reflector 26 can be oriented toward the device under test 12, particularly the test position where the device under test 12 is positioned for testing purposes, while the secondary reflector 28 is oriented toward the quadrature mode converter assembly 16. The reflectors 24 can also be oriented toward each other. Therefore, as... Figure 1 The beam path is established between the quadrature mode converter assembly 16 and the device under test 12 via one or more corresponding reflectors 24.

[0049] In the illustrated embodiment, the quadrature mode converter assembly 16 has two antennas 30, which are pointed towards one or more corresponding reflectors 24, particularly the sub-reflector 28. The antennas 30 are located at the quadrature mode converter assembly 16 such that the antenna phase center spacing is less than 2 cm, for example, approximately 1.6 cm due to a specific arrangement. In other words, in Figure 3 and Figure 4 The orthogonal mode converter assembly 16, shown in more detail, is configured such that at least two antennas 30 are substantially located at the focal point of at least one reflector 24 (i.e., sub-reflector 28).

[0050] In summary, this ensures that the axial ratio and maximum power measurements of the corresponding device under test 12 with one or more dual-polarized antennas can be performed inside an anechoic chamber or, more precisely, an RF shielded chamber 14, without the need for a power supply switch or, more precisely, an antenna locator, such as without moving one or more antennas 30.

[0051] exist Figure 1 In the illustrated embodiment, reflector 24 is located on two different lateral sidewalls, such as a sidewall and a top wall. Of course, reflector 24 could also be located on a sidewall and a bottom wall, or more precisely, on two different sidewalls. The same applies to the orthogonal mode converter assembly 16, which can be associated with a sidewall, a bottom wall, or more precisely, a top wall, depending solely on the overall size of the aerial test system 10.

[0052] exist Figure 2 Another embodiment of the aerial measurement system 10 is shown, which includes only a single reflector 24. Accordingly, Figure 2 The aerial measurement system 10 shown is a single reflector system.

[0053] The single reflector 24 corresponds to the main reflector 26, which is located in the beam path established between the device under test 12 (e.g., the test position of the device under test 12) and the quadrature mode converter assembly 16.

[0054] like Figure 2 As shown, the (fed) antenna 30 of the orthogonal mode transducer assembly 16 is pointed toward the reflector 24, for example, its center, wherein the reflector 24, in particular, its center, is centered relative to the device under test 12 (e.g., the test position of the device under test 12).

[0055] The orthogonal mode converter assembly 16 can be located in a different plane relative to the device under test 12, so that the signal impinging on the reflector 24 (i.e., the main reflector 26) and the signal reflected by the reflector 24 (i.e., the main reflector 26) will not interfere with each other.

[0056] exist Figure 3 and Figure 4 The orthogonal mode converter assembly 16 is shown in more detail, in which it is evident that the orthogonal mode converter assembly 16 includes two measurement modules 32 that are constructed identically.

[0057] Each of the measurement modules 32 includes a housing 34 that respectively houses an orthogonal mode converter 36.

[0058] Accordingly, the antenna 30 of each measurement module 32 is connected to the corresponding quadrature mode converter 36. In fact, both antennas 30 are dual-polarized antennas, which is also... Figure 3 As shown on the right, Figure 3 The corresponding polarization is shown on the right.

[0059] from Figure 3 As can be clearly seen, the orthogonal mode converters 36, and in particular the entire measurement module 32, rotate relative to each other, thereby providing different measurement polarizations for at least two measurement modules 32. Specifically, one of the measurement modules 32 rotates relative to a common reference plane RP, which is a horizontal plane parallel to the polarization reference plane PR1 of one of the measurement modules 32 (e.g., the corresponding orthogonal mode converter 36), while the polarization reference plane PR2 of the other measurement module 32 (e.g., the corresponding orthogonal mode converter 36) is tilted to both the common reference plane RP and the polarization reference plane PR1. In the illustrated embodiment, the corresponding tilt angle is 45°.

[0060] However, the measurement module 32 is fixed in position, making it static and not movable.

[0061] Therefore, due to the tilt / skew arrangement of the measurement module 32, the orthogonal mode converter assembly 16 provides different measurement polarizations. In the illustrated embodiment, the different measurement polarizations are offset from each other by 45°, such as... Figure 3 As shown on the right. Therefore, the two orthogonal mode converters 36, and in particular the associated antenna 30, together provide a total of four different measurement polarizations, namely at 0°, 90° and -45° and +45° relative to the common reference plane RP.

[0062] Figure 4It is also shown that the antennas 30 associated with the output port 38 are far apart from each other, such that the antenna phase center spacing 40 is less than 2 cm, and in particular less than 1.8 cm, so that it is not necessary to position the antennas 30 or more precisely the device under test 12 during testing, because the quiet zone offset is minimized when two antennas 30 are used.

[0063] In addition to the output port 38, each of the corresponding housings 34 also has two input ports 42, through which different polarization signals are received. These signals are processed by the quadrature mode converter 36. In fact, it receives and processes quadrature polarization signals.

[0064] In summary, the orthogonal mode converter 36, at least two antennas 30 and / or measurement module 32 are constructed identically, wherein they are arranged relative to each other in a manner of relative rotation in order to ensure different measurement polarizations are obtained.

[0065] exist Figure 1 and Figure 2 The diagram illustrates a compact antenna test field (CATR) where far-field conditions, such as indirect far-field conditions, are obtained by means of one or more reflectors 24. However, the orthogonal mode converter assembly 16 can also be used in an aerial measurement system 10 without one or more additional reflectors, provided that the appropriate distance is ensured to obtain the far-field conditions for testing the device under test 12. Therefore, the aerial measurement system 10 can also be a far-field system.

[0066] Accordingly, a fast and cost-effective way to perform measurements on dual-polarized devices under test (e.g., antennas under test) is ensured, thanks to the use of the aerial measurement system 10, especially... Figure 3 and Figure 4 The corresponding orthogonal mode converter assembly 16, shown in more detail, can simultaneously perform at least four measurements with four different polarizations.

[0067] Some embodiments disclosed herein, particularly corresponding modules and units, utilize circuit systems (e.g., one or more circuits) to implement the standards, protocols, methods, or techniques disclosed herein, operatively coupling two or more components to generate, process, analyze, generate, encode / decode, convert, transmit and / or receive signals, control other devices, etc. Any type of circuit system can be used.

[0068] In embodiments, the circuit system includes, among other things, one or more computing devices, such as processors (e.g., microprocessors), central processing units (CPUs), digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), system-on-a-chip (SoCs), and any combination thereof; and may include discrete digital or analog circuit elements or electronic devices, or combinations thereof. In embodiments, the circuit system includes hardware circuit implementations (e.g., implementations of analog circuit systems, implementations of digital circuit systems, and combinations thereof).

[0069] In embodiments, the circuit system includes a combination of circuitry and a computer program product having software or firmware instructions stored on one or more computer-readable storage media that work together to cause the device to perform one or more protocols, methods, or techniques described herein. In embodiments, the circuit system includes circuitry, such as circuitry of a microprocessor or portion thereof that requires software, firmware, etc., to operate. In embodiments, the circuit system includes one or more processors or portions thereof, along with accompanying software, firmware, hardware, etc.

[0070] This application may refer to quantities and numbers. Unless otherwise stated, these quantities and numbers should not be considered limiting, but rather examples of possible quantities or numbers associated with this application. Also in this respect, this application may use the term "multiple" to refer to a quantity or number. In this respect, the term "multiple" means any number more than one, such as two, three, four, five, etc. The terms "approximately," "about," "close to," etc., mean plus or minus 5% of a given value.

Claims

1. An aerial measurement system for testing a device under test, wherein, The aerial measurement system includes at least two orthogonal mode converters and at least two antennas, each of which is connected to a dedicated orthogonal mode converter to establish at least two measurement modules. Each orthogonal mode converter is connected to a dedicated output interface and two input interfaces. Each orthogonal mode converter is configured to combine orthogonally polarized signals received via the input interfaces into a combined signal, which is forwarded to the output interface. The at least two orthogonal mode converters are rotated relative to each other to provide different measurement polarizations for the at least two measurement modules relative to a common reference plane. Each of the at least two antennas is a dual-polarized antenna.

2. The aerial measurement system according to claim 1, wherein, The at least two antennas together provide a total of four different measurement polarizations.

3. The aerial measurement system according to claim 1 or 2, wherein, The at least two orthogonal mode converters are arranged relative to each other such that the different measurement polarizations are offset from each other by 45° relative to a common reference plane.

4. The aerial measurement system according to claim 1 or 2, wherein, The number of antennas is equal to the number of orthogonal mode converters.

5. The aerial measurement system according to claim 1 or 2, wherein, The at least two orthogonal mode converters and / or the at least two antennas and / or the at least two measurement modules are constructed identically.

6. The aerial measurement system according to claim 1 or 2, wherein, The antenna phase center spacing is less than 2 cm.

7. The aerial measurement system according to claim 1 or 2, wherein, The aerial measurement system includes at least one reflector.

8. The aerial measurement system according to claim 7, wherein, The at least two antennas are located substantially at the focal point of the at least one reflector.

9. The aerial measurement system according to claim 1 or 2, wherein, Each of the at least two measurement modules includes a housing that accommodates the corresponding orthogonal mode converter.

10. The aerial measurement system according to claim 9, wherein, Each of the at least two measurement modules includes two input ports and one output port, wherein a corresponding antenna is connected to the output port.

11. The aerial measurement system according to claim 1 or 2, wherein, The aerial measurement system includes an RF shielded room.

12. The aerial measurement system according to claim 1 or 2, wherein, The aerial measurement system includes measuring instruments.

13. The aerial measurement system according to claim 1 or 2, wherein, The aerial measurement system includes a locator system for the device under test.

14. The aerial measurement system according to claim 1 or 2, wherein, The aerial measurement system is a far-field system.

15. The aerial measurement system according to claim 1 or 2, wherein, The aerial measurement system is a compact antenna test field system.

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