CN114024807B - Near-field co-channel interference cancellation mechanism and cancellation method - Google Patents
Near-field co-channel interference cancellation mechanism and cancellation method Download PDFInfo
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- CN114024807B CN114024807B CN202111310416.XA CN202111310416A CN114024807B CN 114024807 B CN114024807 B CN 114024807B CN 202111310416 A CN202111310416 A CN 202111310416A CN 114024807 B CN114024807 B CN 114024807B
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- radio frequency
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- frequency signal
- transmitting antenna
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- 238000000034 method Methods 0.000 title claims abstract description 18
- 238000012360 testing method Methods 0.000 claims abstract description 65
- 239000002184 metal Substances 0.000 claims abstract description 25
- 210000001503 joint Anatomy 0.000 claims abstract description 11
- 239000011358 absorbing material Substances 0.000 claims description 12
- 239000002131 composite material Substances 0.000 claims description 2
- 238000004519 manufacturing process Methods 0.000 description 10
- 238000010586 diagram Methods 0.000 description 5
- 230000000903 blocking effect Effects 0.000 description 3
- 230000008054 signal transmission Effects 0.000 description 3
- 230000005540 biological transmission Effects 0.000 description 2
- 230000002159 abnormal effect Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 230000002452 interceptive effect Effects 0.000 description 1
- 238000011056 performance test Methods 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
Classifications
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L25/00—Baseband systems
- H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
- H04L25/03—Shaping networks in transmitter or receiver, e.g. adaptive shaping networks
- H04L25/03006—Arrangements for removing intersymbol interference
- H04L25/03159—Arrangements for removing intersymbol interference operating in the frequency domain
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
- H04B1/06—Receivers
- H04B1/10—Means associated with receiver for limiting or suppressing noise or interference
-
- H04B5/48—
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L25/00—Baseband systems
- H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
- H04L25/03—Shaping networks in transmitter or receiver, e.g. adaptive shaping networks
- H04L25/03006—Arrangements for removing intersymbol interference
- H04L25/03178—Arrangements involving sequence estimation techniques
- H04L25/03248—Arrangements for operating in conjunction with other apparatus
- H04L25/0328—Arrangements for operating in conjunction with other apparatus with interference cancellation circuitry
Abstract
The invention belongs to the field of radio frequency signal testing, and relates to a near-field co-frequency interference cancellation mechanism and a cancellation method. The counteracting mechanism comprises an instruction radio frequency signal shielding mechanism and an image radio frequency signal shielding mechanism; the instruction radio frequency signal shielding mechanism comprises a metal shielding cavity (15), one end in the metal shielding cavity (15) is provided with an instruction transmitting antenna (5), and the other end is in butt joint with an instruction receiving antenna (3) of the equipment during testing; the transmitting antenna (5) is instructed to serve as the transmitting antenna of the test equipment; the image radio frequency signal shielding mechanism comprises a metal shielding cavity (15), wherein one end in the metal shielding cavity (15) is provided with an image receiving antenna (6) and an attenuator (18) which are connected through signals, and the other end is in butt joint with an equipped image transmitting antenna (4) during testing; during testing, the attenuator (18) is connected with the testing device, and the image receiving antenna (6) is used as a receiving antenna of the testing device. The mechanism can realize that a plurality of devices perform ground test together, and avoids the same-frequency interference.
Description
Technical Field
The invention belongs to the field of radio frequency signal testing, and particularly relates to a near-field co-frequency interference cancellation mechanism and a cancellation method.
Background
Near field co-channel interference refers to the influence of nearby co-channel signals transmitted with high power on the receiver performance. Co-channel interference can overwhelm the receiver with the desired signal, can combine with the desired signal to cause severe distortion of the detected output, or can cause the automatic frequency control circuit to retune to the interfering frequency.
And a certain device is provided with an image transmitting system and an instruction receiving system, and an image instruction radio frequency signal is required to be subjected to receiving and transmitting functions and sensitivity function inspection when the ground performance test is carried out. The equipment adopts the same working frequency during ground test, and during test work, the equipment has a large number of bootable devices and can generate frequency interference phenomenon when the distance is short, so that the reality of image receiving and instruction transmitting is affected, the test flow is abnormal, and the detection result of the equipment is misled.
The conventional common-frequency anti-interference method at the present stage performs test work for each equipment in a staggered time, and can avoid common-frequency interference but influence the production efficiency of a production workshop.
Disclosure of Invention
The invention aims to: the radio frequency emission signals of the test equipment are physically connected with the equipment receiver, the equipment emission antenna is physically connected with the test equipment receiver, mutual interference with test signals of other products is avoided, ground test of a plurality of weaponry equipment can be achieved, and production efficiency of a production workshop is improved. Further, a design method of the near-field co-frequency interference cancellation mechanism is provided.
The technical scheme is as follows: providing a near-field co-frequency interference cancellation mechanism, wherein the cancellation mechanism comprises an instruction radio frequency signal shielding mechanism and an image radio frequency signal shielding mechanism;
the instruction radio frequency signal shielding mechanism comprises a metal shielding cavity 15, wherein an instruction transmitting antenna 5 is arranged at one end in the metal shielding cavity 15, and the other end is in butt joint with an instruction receiving antenna 3; the instruction transmitting antenna 5 is used as a transmitting antenna of the test equipment;
the image radio frequency signal shielding mechanism comprises a metal shielding cavity 15, wherein one end in the metal shielding cavity 15 is provided with an image receiving antenna 6 and an attenuator 18 which are connected through signals, and the other end is in butt joint with an equipped image transmitting antenna 4 during testing; in the test, the attenuator 18 is connected with the test equipment, and the image receiving antenna 6 is used as a receiving antenna of the test equipment;
the inner cavity surface of the metal shielding cavity 15 is provided with a wave absorbing material layer 16.
Optionally, a conductive rubber 14 is mounted at the interface of the metal shielding cavity 15 and the equipped instruction receiving antenna 3, so as to avoid signal leakage at the interface.
Optionally, a conductive rubber 14 is mounted at the interface of the metal shielding cavity 15 and the equipped image transmitting antenna 4, so as to avoid signal leakage at the interface.
Optionally, the instruction transmitting antenna 5 is connected to the test equipment by a feeder connector 17; the attenuator 18 is connected to the test equipment by means of a feeder connection 17.
Optionally, the metallic shielding cavity 15 is a cylindrical structure.
Optionally, the image transmission power of the equipment is greater than 30Hz.
Alternatively, the wave-absorbing material layer 16 is made of nano wave-absorbing material or wave-absorbing structure composite material.
In another aspect, there is provided a near field co-channel interference cancellation method, using the cancellation mechanism as described above, the method comprising:
when testing a plurality of devices, the instruction receiving antenna 3 of a single device is in butt joint with the instruction radio frequency signal shielding mechanism, and the image transmitting antenna 4 is in butt joint with the image radio frequency signal shielding mechanism; the instruction transmitting antenna 5 is connected with the signal of the test equipment, the image receiving antenna 6 is connected with the signal of the test equipment, the instruction transmitting antenna 5 is used as the transmitting antenna of the test equipment, and the image receiving antenna 6 is used as the receiving antenna of the test equipment.
The invention has the technical effects that: the near-field co-frequency interference cancellation mechanism can realize that a plurality of devices perform ground test together on the premise of not influencing the transmission and the reception of radio frequency signals, and the method can avoid co-frequency interference and improve the test efficiency of a production workshop.
Drawings
FIG. 1 is a schematic diagram of near field co-frequency RF signal interference;
FIG. 2 is a frame diagram of the co-channel interference cancellation mechanism;
FIG. 3 is a frame diagram of an instruction RF signal shielding mechanism;
FIG. 4 is a frame diagram of an image RF signal shielding mechanism;
reference numerals illustrate: 1 equipment, 2 test equipment, 3 instruction receiving antenna, 4 image transmitting antenna, 5 instruction transmitting antenna, 6 image receiving antenna, 7 useful signal, 8 interference signal, 9 instruction radio frequency signal transmission mechanism, 10 image radio frequency signal transmission mechanism, 11 instruction radio frequency feeder, 12 image radio frequency feeder, 13 support, 14 conductive rubber, 15 metal shielding layer, 16 wave absorbing material layer, 17 feeder joint, 18 attenuator.
Detailed Description
As shown in fig. 1, fig. 1 is a schematic diagram of mutual interference of near-field co-frequency rf signals. The conventional common-frequency anti-interference method at the present stage performs test work for each equipment weapon at a time, and can avoid common-frequency interference but influence the production efficiency of a production workshop.
Therefore, the invention is designed for solving the problem that the frequency interference phenomenon occurs when the equipment is started up in a large quantity and is close in distance during the test work, and the invention is designed under the condition that the existing equipment structure is not changed and the test time is not increased.
Example 1
The embodiment provides a near field co-frequency interference cancellation mechanism, and this mechanism includes instruction radio frequency signal shielding mechanism, image radio frequency signal shielding mechanism and support as shown in fig. 2, and the support is general camera support, can adjust the height according to equipment weapon, and instruction radio frequency signal shielding mechanism, image radio frequency signal shielding mechanism design is as follows:
a) Instruction radio frequency signal shielding mechanism
The instruction radio frequency signal shielding mechanism comprises an instruction transmitting antenna 3, a metal shielding cavity 15, a wave absorbing material layer 16, conductive rubber 14 and a feeder line connector 17, and the structural design is shown in figure 3. The method comprises the steps that an instruction transmitting antenna of ground test equipment is arranged in an instruction radio frequency signal shielding mechanism, and an instruction radio frequency signal sent by the ground test equipment is sent out through the instruction transmitting antenna; the metal shielding cavity and the wave-absorbing material layer play a role in shielding the instruction radio frequency signals; the conductive rubber plays a role in effectively transmitting radio frequency signals received by the instruction receiving antenna; the feeder line connector is a plug for instructing the radio frequency signal shielding mechanism to connect with the test equipment.
b) Image radio frequency signal shielding mechanism
The image radio frequency signal shielding mechanism comprises an image receiving antenna 6, an attenuator 18, a metal shielding cavity 15, a wave absorbing material layer 16, conductive rubber 14 and a feeder line joint 17, and the structural design is shown in fig. 4. An image receiving antenna of the ground test equipment is internally provided with an image radio frequency signal shielding mechanism, and an image radio frequency signal sent by equipment is regulated by the image receiving antenna through an attenuator and is sent to the ground test equipment; the metal shielding cavity and the wave-absorbing material layer play a role in shielding the instruction radio frequency signals; the conductive rubber plays a role in effectively transmitting radio frequency signals sent by the equipped image transmitting antenna; the feeder line connector is a plug for connecting the image radio frequency signal shielding mechanism with the testing equipment.
In this embodiment, the image transmitting power of the device is greater than 30Hz, and in the metal shielding cavity, the image high-power signal may cause signal blocking of the test device, and the signal is adjusted to a suitable range by the attenuator, so as to avoid signal blocking of the test device.
The specific implementation method of the embodiment comprises the following steps:
aiming at mutual interference of near-field same-frequency radio frequency signals, the requirement of workshop production efficiency cannot be met. The same-frequency interference cancellation mechanism is designed. The mechanism comprises a command radio frequency signal shielding mechanism 9, an image radio frequency signal shielding mechanism 10 and a bracket 13.
The instruction radio frequency signal shielding mechanism 9 and the image radio frequency signal shielding mechanism 10 are made of a wave absorbing material layer 16, and a metal shielding layer is arranged outside. The contact positions of the instruction receiving antenna 3 and the image transmitting antenna 4 of the equipment 1 and the instruction radio frequency signal shielding mechanism 9 and the image radio frequency signal shielding mechanism 10 are respectively provided with conductive rubber 14, and the conductive rubber plays a role in effectively transmitting radio frequency signals received by the instruction receiving antenna 3 of the equipment weapon and sent by the image transmitting antenna 4.
In order to reduce signal blocking of the image signal in the image radio frequency signal shielding mechanism, an attenuator 18 is arranged in the image radio frequency signal shielding mechanism, attenuation values can be adjusted according to signal intensity, and the feeder line connector 17 can be connected with external test equipment.
In the test process, an instruction radio frequency signal sent by the test equipment 2 is transmitted to an instruction transmitting antenna 5 in the shielding mechanism through an instruction radio frequency feeder line 11 and a feeder line joint 17, and the instruction radio frequency signal is transmitted to an instruction receiving antenna 3 of the equipment 1 through an instruction radio frequency signal shielding mechanism; in the testing process, the image radio frequency signal sent by the equipment 1 is transmitted to the image receiving antenna 6 in the image radio frequency signal shielding mechanism by the image transmitting antenna 4 through the image radio frequency signal shielding mechanism, the image receiving antenna 6 carries out radio frequency signal adjustment on the received radio frequency signal through the attenuator 18, and the radio frequency signal is transmitted to the testing equipment 2 through the feeder line connector 17 and the image radio frequency feeder line 12. In the whole test process, radio frequency signals are transmitted through the instruction radio frequency signal shielding mechanism 9 and the image radio frequency signal shielding mechanism 10, so that signal leakage can not be generated, and radio frequency signal transmission of other 2 test devices in the same place can not be influenced.
The design can avoid the interference signal 8 generated by the leakage of the radio frequency signal, interfere the testing tasks of other equipment, and ensure that the useful signal 7 is transmitted according to a designated path without influencing the sending and receiving of the testing instruction. The design of the near-field co-frequency interference cancellation mechanism can realize that a plurality of weaponry can be used for ground test together, and the method can avoid co-frequency interference and improve the production efficiency of a production workshop.
Claims (8)
1. The near-field co-frequency interference cancellation mechanism is characterized by comprising an instruction radio frequency signal shielding mechanism and an image radio frequency signal shielding mechanism;
the instruction radio frequency signal shielding mechanism comprises a metal shielding cavity (15), one end in the metal shielding cavity (15) is provided with an instruction transmitting antenna (5), and the other end is in butt joint with an instruction receiving antenna (3) of the equipment during testing; the transmitting antenna (5) is instructed to serve as the transmitting antenna of the test equipment;
the image radio frequency signal shielding mechanism comprises a metal shielding cavity (15), wherein one end in the metal shielding cavity (15) is provided with an image receiving antenna (6) and an attenuator (18) which are connected through signals, and the other end is in butt joint with an equipped image transmitting antenna (4) during testing; during testing, the attenuator (18) is connected with the testing equipment, and the image receiving antenna (6) is used as a receiving antenna of the testing equipment;
the inner cavity surface of the metal shielding cavity (15) is provided with a wave absorbing material layer (16).
2. The near field co-channel interference cancellation mechanism of claim 1 wherein,
and a conductive rubber (14) is arranged at the joint of the metal shielding cavity (15) and the equipped instruction receiving antenna (3) and is used for avoiding signal leakage at the joint.
3. The near field co-channel interference cancellation mechanism of claim 1 wherein,
and a conductive rubber (14) is arranged at the butt joint of the metal shielding cavity (15) and the equipped image transmitting antenna (4) and is used for avoiding signal leakage at the interface.
4. Near field co-channel interference cancellation mechanism according to claim 1, characterized in that the instruction transmitting antenna (5) is connected to the test equipment by means of a feeder connection (17); the attenuator (18) is connected to the test device via a feeder connection (17).
5. The near field co-channel interference cancellation mechanism according to claim 1, wherein the metallic shielding cavity (15) is of cylindrical structure.
6. The near field co-channel interference cancellation mechanism of claim 1 wherein the equipped image transmit power is greater than 30Hz.
7. The near field co-channel interference cancellation mechanism according to claim 1, wherein the wave-absorbing material layer (16) is selected from nano wave-absorbing materials or wave-absorbing structure composite materials.
8. A near field co-channel interference cancellation method using the cancellation mechanism of any one of claims 1 to 6, the method comprising:
when a plurality of devices are tested, the instruction receiving antenna (3) of the single device is in butt joint with the instruction radio frequency signal shielding mechanism, and the image transmitting antenna (4) is in butt joint with the image radio frequency signal shielding mechanism; the instruction transmitting antenna (5) is connected with the signal of the test equipment, the image receiving antenna (6) is connected with the signal of the test equipment, the instruction transmitting antenna (5) is used as the transmitting antenna of the test equipment, and the image receiving antenna (6) is used as the receiving antenna of the test equipment.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111310416.XA CN114024807B (en) | 2021-11-05 | 2021-11-05 | Near-field co-channel interference cancellation mechanism and cancellation method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111310416.XA CN114024807B (en) | 2021-11-05 | 2021-11-05 | Near-field co-channel interference cancellation mechanism and cancellation method |
Publications (2)
| Publication Number | Publication Date |
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| CN114024807A CN114024807A (en) | 2022-02-08 |
| CN114024807B true CN114024807B (en) | 2024-04-05 |
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| CN202111310416.XA Active CN114024807B (en) | 2021-11-05 | 2021-11-05 | Near-field co-channel interference cancellation mechanism and cancellation method |
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