CN109239472B - Antenna radiation pattern measuring system applied to multi-path environment - Google Patents
Antenna radiation pattern measuring system applied to multi-path environment Download PDFInfo
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- CN109239472B CN109239472B CN201710560850.0A CN201710560850A CN109239472B CN 109239472 B CN109239472 B CN 109239472B CN 201710560850 A CN201710560850 A CN 201710560850A CN 109239472 B CN109239472 B CN 109239472B
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- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R29/00—Arrangements for measuring or indicating electric quantities not covered by groups G01R19/00 - G01R27/00
- G01R29/08—Measuring electromagnetic field characteristics
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Abstract
An antenna radiation pattern measuring system applied in a multi-path environment comprises a first rotating part, a rotating arm, a transmitting antenna, a reflector, a bracket and a second rotating part. The fixed end of the rotating arm is connected with the first rotating part. The transmitting antenna is arranged on the spiral arm, the distance between the reflector arranged at the free end of the spiral arm and the transmitting antenna is kept fixed, and the first rotating part drives the spiral arm to rotate so that the reflector rotates around the first central axis. The positioning portion of the bracket positions the electronic device at a position of the first central axis of the first rotating portion. The distance between the reflector and the electronic device is not only kept fixed but also is a straight line which is connected in space and is perpendicular to the first central axis. The second rotating part enables the support to rotate in place according to a second central axis perpendicular to the first central axis. Therefore, the radiation field pattern of at least one antenna to be tested of the electronic device is obtained.
Description
Technical Field
The present invention relates to an antenna measurement system, and more particularly, to an antenna radiation pattern measurement system applied in a multi-path environment.
Background
Conventionally, the radiation pattern measurement of the antenna requires a tightly controlled measurement environment and precise measurement equipment. The traditional metrology environment uses an anechoic chamber (anechoic chamber), which generally needs to meet two conditions to achieve ideal free space (free space): generally, an electromagnetic wave shield of an all-metal structure is used to shield the interference of external electromagnetic wave signals, and an electromagnetic wave absorbing member is provided in the anechoic chamber to constitute the anechoic chamber. Although the anechoic chamber can provide a reflection-free and interference-free measurement environment, the installation cost is proportional to the measurement dynamic range of the anechoic chamber. With respect to the high measurement cost, the radiation pattern measurement applied to the conventional line of Sight (LOS) antenna measurement (e.g., a highly directional antenna such as a base station antenna) can obtain a very accurate and effective antenna performance evaluation.
Conventional anechoic chamber and antenna measurement equipment is divided into near-field measurement and far-field measurement. Near-field measurement is a method of converting near-field measurement data into far-field data through mathematical operations, and may not be converted into actual results of real products in far-field applications only through ideal mathematical models due to many differences in physical structures of various wireless communication products. However, the problem encountered in far-field measurement is that, depending on the operating wavelength (or frequency) of the antenna, the anechoic chamber needs a large enough space, the anechoic chamber cannot be reduced without limitation (the space occupied by the anechoic chamber equipment in a factory building or a research and development organization is a large cost), a sufficient distance is required between the antenna to be measured and a signal emission source to meet the far-field condition, a proper far-field dead Zone (quench Zone) needs to be planned, and particularly, the volume of the anechoic chamber meeting the far-field condition is large when the operating wavelength of the antenna is long. Furthermore, the conventional antenna measurement in the anechoic chamber uses the line-of-sight distance as the required standard, and not only the strong signal receiving condition of the antenna but also the receiving condition of the dead zone (null) of the receiving signal need to be measured.
Disclosure of Invention
The embodiment of the invention discloses an antenna radiation pattern measuring system applied to a multipath environment, wherein an antenna applied to the multipath environment only needs to master the strong signal receiving area condition of the antenna and does not need to accurately obtain the signal receiving condition of a dead angle, for example, the performance of a common small electronic device with wireless communication capability in practical application is related to multipath caused by the use environment. Accordingly, the requirement for measuring the radiation characteristics of the antenna applied in the multipath environment is different from the requirement for very accurate measurement of a high-directivity antenna applied in the line-of-sight distance environment, the high-directivity antenna needs to accurately measure the strength of a signal (including a main beam, a lobe and a null (null) between lobes) at various angles, the radiation characteristics of the high-directivity antenna such as a base station antenna are adjusted according to the direction of the user equipment, no user direction needs no radiation to save power consumption, and on the other hand, the radiation characteristics (radiation field pattern) of the antenna of a small electronic device (generally an antenna) having a wireless communication function are mainly focused on the direction in which the signal reception (or emission) is strong, and are not focused on the measurement of the radiation characteristics in the direction in which the signal reception (or emission) is weak. The embodiment of the invention is an antenna radiation pattern measuring system applied to a multipath environment, is different from a traditional near-field measuring system and a far-field measuring system of a line-of-sight distance measuring framework, is a compromise scheme obtained by taking a trade-off between the requirements of measuring target accuracy and system construction cost control, can create outstanding measuring efficiency different from the traditional measuring scheme, and can replace the traditional radiation pattern measuring system when an antenna is applied to a multipath condition.
The embodiment of the invention discloses an antenna radiation pattern measuring system applied to a multipath environment. The spiral arm is provided with a fixed end and a free end, and the fixed end is connected with the first rotating part. The transmission antenna is arranged on the spiral arm. The reflector is arranged at the free end of the rotating arm, the distance between the reflector and the transmitting antenna is kept fixed, and the first rotating part drives the rotating arm to rotate so that the reflector at the free end rotates around the first central axis of the first rotating part. The bracket keeps a set distance from the fixed end of the radial arm. The positioning part of the bracket is used for positioning an electronic device at a position of the first central axis of the first rotating part. The reflector is used for reflecting the electromagnetic wave from the transmitting antenna to at least one adjacent antenna of the electronic device, the distance between the reflector and the electronic device is kept fixed, and a straight line formed by the reflector and the electronic device in space is perpendicular to a first central axis of the first rotating part. The second rotating part is connected with the support, so that the support rotates in place according to a second central axis, and the second central axis is perpendicular to the first central axis.
Preferably, the transmitting antenna is a horn antenna.
Preferably, the reflector is a parabolic reflector or a flat reflective plate.
Preferably, the antenna radiation pattern measuring system applied in the multipath environment is installed in an anechoic chamber.
Preferably, the antenna radiation pattern measurement system applied in a multi-path environment is configured to be disposed in a multi-path measurement environment.
Preferably, the electronic device is a notebook computer, a laptop computer, a tablet computer, an all-in-one computer, a smart television, a small base station, a router, or a smartphone.
Preferably, the antenna radiation pattern measuring system applied in the multi-path environment is used for measuring a two-dimensional (2D) or three-dimensional (3D) radiation pattern of the electronic device, the rotation angle of the swing arm represents an angle θ of a spherical coordinate, and the rotation of the support represents an angle φ of the spherical coordinate.
Preferably, the frequency of the electromagnetic wave transmitted by the transmitting antenna is in a 700MHz frequency band, an 800MHz frequency band, a 900MHz frequency band, a 3.3GHz to 3.6GHz, a 4.4GHz to 4.5GHz, a 4.8GHz to 4.99GHz, or a 5.9GHz frequency band.
Preferably, the frequency of the electromagnetic wave transmitted by the transmitting antenna is in the 25GHz, 26GHz, 28GHz, 30GHz or 40GHz band of the millimeter wave.
Preferably, the frequency of the electromagnetic wave transmitted by the transmitting antenna is in the frequency band of the wireless local area network of the IEEE 802.11 standard.
In summary, the embodiments of the present invention provide an antenna radiation pattern measurement system applied in a multipath environment, which can increase a far-field dead Zone (quench Zone) while reducing the system size. By using a reflector to transmit electromagnetic waves of plane waves (or approximate plane waves) provided by an antenna to (at least one antenna to be tested of) an electronic device to be tested, the measuring system can provide sufficiently accurate measurement for a main Beam or a stronger Lobe (Lobe or Beam) of a radiation pattern of the antenna, and the accuracy of the intensity of a null point (null) between the lobes is ignored, so that the measuring system with lower cost and accuracy is consistent with the radiation pattern required by being applied to a multi-path antenna.
Drawings
Fig. 1 is a schematic diagram of an antenna radiation pattern measurement system applied in a multi-path environment according to an embodiment of the present invention.
Fig. 2 is a side view of an antenna radiation pattern measuring system applied in a multi-path environment according to an embodiment of the present invention.
Fig. 3 is a schematic view illustrating a measurement operation state of an antenna radiation pattern measurement system applied in a multi-path environment according to an embodiment of the present invention.
Fig. 4A is a radiation pattern diagram obtained by a conventional line of Sight (LOS) antenna measurement method.
Fig. 4B is a radiation pattern diagram measured by the antenna radiation pattern measuring system applied in the multi-path environment according to the embodiment of the present invention.
Detailed Description
The antenna applied to the multi-path environment is more focused on the overall signal receiving capability, and if the antenna has a possible dead angle (or weak position), the measurement accuracy for the dead angle (or weak position) is less focused. The antenna radiation pattern measurement system applied to the multi-path environment of the embodiment of the present invention is a compromise solution obtained by taking a trade-off between measurement target accuracy and system construction cost control, but can create a prominent measurement performance different from the conventional measurement scheme, and can replace the conventional radiation pattern measurement system when applied to the multi-path environment.
Referring to fig. 1, an antenna radiation pattern measuring system applied in a multipath environment according to an embodiment of the present invention includes a first rotating portion 11, a rotating arm 12, a transmitting antenna 13, a reflector 14, a bracket 15, and a second rotator 16. The first rotating part 11 and the second rotating part 16 are preferably disposed on the system base 17 to maintain the relative distance between the radial arm 12 and the bracket 15 and the stability of the whole system. However, the first rotating part 11 and the second rotating part 16 may be directly installed on a solid ground (e.g., a flat floor of any floor of a building).
The swing arm 12 has a fixed end 121 and a free end 122, and the fixed end 121 is connected to the first rotating part 11. The transmission antenna 13 is provided to the arm 12. The reflector 14 is disposed at the free end 122 of the radial arm 12, the distance DA between the reflector 14 and the transmitting antenna 13 is kept constant, and the first rotating portion 11 drives the radial arm 12 to rotate so that the reflector 14 at the free end 122 rotates around a first central axis of the first rotating portion 11, where the first central axis is an X axis in fig. 1. The bracket 15 is kept at a set distance DS from the fixed end 121 of the swing arm 12, and the bracket 15 has a positioning portion 151, and the positioning portion 151 is used for positioning an electronic device (not shown in fig. 1) having at least one antenna to be tested at a position PA of the first central axis (X axis) of the first rotating portion 11.
Referring to fig. 1 and 2 together, the reflector 14 is used for reflecting the electromagnetic wave from the transmitting antenna 13 to the electronic device 21. Also, since the distance between the free end 122 of the radial arm 12 and the first central axis (X-axis) is kept constant, the distance DB between the electronic device 21 and the reflector 14 at the free end 122 of the radial arm 12 and the electronic device 21 can be kept constant. A straight line spatially connecting the reflector 14 and the electronic device 21 is perpendicular to the first central axis (X axis) of the first rotating portion 11, that is, a line connecting the distance DB is perpendicular to the X axis. The second rotating portion 16 is connected to the bracket 15, so that the bracket 15 rotates in place according to a second central axis (the electronic device 21 fixed to the bracket 15 also rotates in place according to the second central axis), the second central axis is perpendicular to the first central axis (X axis), the second central axis in fig. 1 and 2 is a Y axis, and a connecting line of the middle distance DB in this embodiment is coincident with the second central axis (Y axis).
The transmitting antenna 13 is used to generate electromagnetic wave source, such as a horn antenna, but the invention is not limited thereto. The frequency of the electromagnetic wave transmitted by the transmission antenna 13 is, for example, a frequency band of 700MHz, a frequency band of 800MHz, a frequency band of 900MHz, a frequency band of 3.3GHz to 3.6GHz, a frequency band of 4.4GHz to 4.5GHz, a frequency band of 4.8GHz to 4.99GHz, or a frequency band of 5.9 GHz. For another example, the frequency of the electromagnetic wave transmitted by the transmission antenna 13 is in the 25GHz, 26GHz, 28GHz, 30GHz, or 40GHz band of the millimeter wave. For another example, the frequency of the electromagnetic wave transmitted by the transmitting antenna 13 is in the Wireless Local Area Network (WLAN) band of the IEEE 802.11 standard, but the present invention is not limited thereto. The reflector 14 is used to reflect the electromagnetic wave from the transmitting antenna 13. The reflector 14 is, for example, a parabolic reflector or a flat reflector, which is preferably made of metal, but the invention is not limited thereto. The total reflection path length obtained by summing the distance DA and the distance DB is such that the electromagnetic wave received by (at least one antenna under test of) the electronic device 21 under test is a planar electromagnetic wave (or a near-planar electromagnetic wave), and meets (or approaches) the far-field condition. Also, because the reflection path is used, the line of Sight (LOS) measurement architecture is not used, so that the occupied space required by the measurement system can be greatly reduced.
Referring to fig. 3, fig. 3 is a schematic view illustrating a measurement operation state of an antenna radiation pattern measurement system applied in a multi-path environment according to an embodiment of the present invention. The antenna radiation pattern measuring system applied to the multi-path environment is used for measuring a two-dimensional (2D) or three-dimensional (3D) radiation pattern of an electronic device, the rotation angle of the rotary arm 12 represents an angle theta of a spherical coordinate, and the rotation of the support 15 represents an angle phi of the spherical coordinate. Depending on the actual arrangement, the angle of rotation θ of the radial arm 12 may be from zero to 90 degrees, or even 180 degrees, and it should be noted that when the angle of rotation θ of the radial arm 12 is greater than 90 degrees or even 180 degrees, the space below must be sufficient to prevent the ground and associated support structure (e.g., the system base 17 of fig. 1) from blocking the rotation of the free end 122 of the radial arm 12.
The antenna radiation pattern measurement system applied to the multipath environment of the embodiment is used for being arranged in an anechoic chamber or being arranged in the multipath measurement environment. The radiation field type measurement system of the electronic device in the anechoic chamber can reduce the cost of wave absorber materials (due to the reduction of the volume of the anechoic chamber) required by the traditional far-field measurement of the anechoic chamber. The main beam (or at least one stronger lobe) for the measurement electronics, and omits the partial accuracy of the intensity of the lobe-to-lobe null (null). Referring to fig. 4A and 4B, fig. 4A shows an example of a radiation pattern measured by a conventional line of Sight (LOS) antenna measurement method in a anechoic chamber, where a main beam (and side lobes) are distinct (including peaks) and accurate, and null points (null) between the lobes, such as N1, N2, N3, N3, N4, and N5, also represent the measurement accuracy. Compared with fig. 4A, for the same electronic device under test, fig. 4B is a radiation field pattern obtained by using the overhead radiation field pattern measuring system of the embodiment of the present invention in the anechoic chamber, and it can be seen that the lobe in fig. 4B is not as accurate (has larger distortion) as that in fig. 4A, but the peaks P1, P2, P3, P4, and P5 of the main beam (and the side lobe) are very close to or almost the same as those in fig. 4A.
On the other hand, the antenna radiation pattern measuring system applied in the multi-path environment can be directly installed in the multi-path measuring environment when the environmental interference is small, the multi-path measuring environment is a non-shielded space, which is an application scenario (such as offices, floors in buildings, parking lots, etc.) of a small electronic device with a wireless communication function in general, and can change the surrounding measuring environment according to the application attributes of the product, the application environment of the electronic device product has a common point that the multi-path effect is caused by surrounding objects, the main beam (or at least one stronger lobe) of the electronic device for which the radiation pattern measuring system is used in the multi-path effect has no problem, and the partial accuracy of the intensity of the null point (null) between the lobes is ignored for the electronic device, the lobe null (null) of the radiation pattern is not important. Therefore, the method can give consideration to both the actual field measurement and the measurement accuracy.
In summary, the antenna radiation pattern measurement system applied in the multi-path environment provided by the embodiments of the present invention can increase a far-field dead Zone (quench Zone) under the condition of reducing the system volume. The reflector is used to transmit the electromagnetic wave of plane wave (or close to plane wave) provided by the antenna to the electronic device to be measured, so that the measuring system can provide sufficiently accurate measurement for the main Beam or stronger Lobe (Lobe or Beam) of the radiation pattern, and the partial accuracy of the intensity of the null point (null) between the lobes is ignored, thereby providing a radiation pattern measuring system with lower cost and satisfactory accuracy. In addition, the antenna radiation pattern measurement system applied to the multipath environment does not need to be arranged in a anechoic chamber, can be specially applied to the multipath measurement environment, and can measure the main beam or the stronger lobe of the electronic device to be measured.
The above description is only an example of the present invention, and is not intended to limit the scope of the present invention.
Reference numerals
11: first rotating part
12: rotary arm
13: transmission antenna
14: reflector
15: support frame
16: second rotating part
121: fixed end
122: free end
DA: distance between each other
X: first central axis
And (2) DS: set distance
151: positioning part
21: electronic device
PA: position of
DB: distance between each other
Y: second central axis
17: system base
N1, N2, N3, N3, N4, N5: zero point
P1, P2, P3, P4, P5: at the peak
θ, φ: corner
Claims (10)
1. An antenna radiation pattern measurement system applied in a multi-path environment, comprising:
a first rotating part;
a rotating arm having a fixed end and a free end, the fixed end being connected to the first rotating portion;
a transmission antenna arranged on the spiral arm;
a reflector disposed at the free end of the rotating arm, wherein the distance between the reflector and the transmitting antenna is kept fixed, and the first rotating part drives the rotating arm to rotate so that the reflector at the free end rotates around a first central axis of the first rotating part;
a bracket, keeping a set distance with the fixed end of the rotating arm, having a positioning part, for positioning an electronic device at a position of the first central axis of the first rotating part, wherein the reflector is used for reflecting the electromagnetic wave from the transmitting antenna to at least one antenna to be tested of the electronic device, the distance between the reflector and the electronic device is kept fixed, and a line spatially connected between the reflector and the electronic device is perpendicular to the first central axis of the first rotating part; and
and the second rotating part is connected with the bracket to enable the bracket to rotate in situ according to a second central axis, and the second central axis is vertical to the first central axis.
2. The system of claim 1, wherein the transmitting antenna is a horn antenna.
3. The system of claim 2, wherein the reflector is a parabolic reflector or a flat reflector.
4. The system of claim 1, wherein the system is installed in a anechoic chamber.
5. The system of claim 1, wherein the system is configured to be disposed in a multi-path measurement environment.
6. The system of claim 1, wherein the electronic device is a notebook computer, a laptop computer, a tablet computer, an all-in-one computer, a smart tv, a small base station, a router, or a smart phone.
7. The system of claim 1, wherein the antenna radiation pattern measuring system is configured to measure a two-dimensional or three-dimensional radiation pattern of the electronic device, the rotation angle of the arm represents θ of a spherical coordinate, and the rotation of the bracket represents φ of a spherical coordinate.
8. The system of claim 1, wherein the frequency of the electromagnetic wave transmitted by the transmitting antenna is in the 700MHz band, the 800MHz band, the 900MHz band, the 3.3 GHz-3.6 GHz band, the 4.4 GHz-4.5 GHz band, the 4.8 GHz-4.99 GHz band, or the 5.9GHz band.
9. The system of claim 1, wherein the frequency of the electromagnetic waves transmitted by the transmitting antenna is in the 25GHz, 26GHz, 28GHz, 30GHz or 40GHz band of millimeter waves.
10. The system of claim 1, wherein the frequency of the electromagnetic waves transmitted by the transmitting antenna is within the frequency band of the WLAN of IEEE 802.11 standard.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN112230071B (en) * | 2019-07-15 | 2024-04-12 | 川升股份有限公司 | Antenna radiation measuring system for improving radio frequency signal stability |
| CN112557766A (en) * | 2019-09-10 | 2021-03-26 | 川升股份有限公司 | Antenna measurement system for multiple-input multiple-output air transmission |
| CN113030597B (en) * | 2019-12-24 | 2024-05-17 | 川升股份有限公司 | Antenna measuring system integrating far field and distance-reducing field |
| CN113960378A (en) * | 2020-07-20 | 2022-01-21 | 川升股份有限公司 | Quasi-far-field measurement system and quasi-far-field measurement method |
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| JPH0949860A (en) * | 1995-08-09 | 1997-02-18 | Mitsubishi Electric Corp | Antenna measuring apparatus |
| CN101056149A (en) * | 2006-04-13 | 2007-10-17 | 智邦科技股份有限公司 | Testing apparatus and method for a multi-paths simulating system |
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