CN113938147B - Method for eliminating strong electromagnetic interference signal leaked by transmitter - Google Patents
Method for eliminating strong electromagnetic interference signal leaked by transmitter Download PDFInfo
- Publication number
- CN113938147B CN113938147B CN202111144835.0A CN202111144835A CN113938147B CN 113938147 B CN113938147 B CN 113938147B CN 202111144835 A CN202111144835 A CN 202111144835A CN 113938147 B CN113938147 B CN 113938147B
- Authority
- CN
- China
- Prior art keywords
- signal
- transmitter
- electromagnetic interference
- signals
- interference
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- 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
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Noise Elimination (AREA)
Abstract
The invention discloses a method for eliminating strong electromagnetic interference signals leaked by a transmitter, which is directly coupled to a reference signal through the output end of the transmitter. And after the reference signals are subjected to orthogonal separation, an adjustable gain amplifier is used for carrying out adjustable delay, and the received signals with interference received by the receiving antenna are approached. And superposing the received signal and the reference signal to obtain a feedback signal, inputting the feedback signal into an integrator, tracking the correlation between the received signal and the reference signal by using the integrator, and further adjusting the reference signal by applying the output of the integrator to the adjustable gain amplifier. Until a cancellation signal is generated that is equal in magnitude and opposite in phase to the interference signal. After the offset signal and the receiving signal are superposed, the elimination of the interference signal can be realized. The method can cancel the electromagnetic interference signals at the front end of the low-noise amplifier and the rear end of the receiving antenna in the whole receiver link, thereby avoiding the saturation of the rear end circuit.
Description
Technical Field
The invention belongs to the technical field of electromagnetic fields, relates to a method for counteracting anti-electromagnetic interference signals, and particularly relates to a method for eliminating strong electromagnetic interference signals leaked by a transmitter.
Background
In an environment of strong electromagnetic leakage, there is a leakage signal from the transmitter in addition to the signal from the target for the receiver. The electromagnetic interference signal leaks by the following mechanisms: (1) coupling through a substrate of a chip; (2) coupling caused by chip-antenna interconnects; and (3) mutual coupling between the transmitting and receiving antennas. For a compact transmit receive type module: the isolation between transmitter and receiver can be reasonably set to 30dB, assuming a transmitter output power of 10dBm, then-20 dBm of signal power is received at the input of the receiver. In this case, the power of the interference signal of the electromagnetic leakage may be several orders of magnitude higher than the power of the received target signal. High power electromagnetic interference signals limit the linearity and resolution of the receiver of the ADC, resulting in increased circuit area and increased power consumption.
Therefore, it is of great significance to shield or eliminate electromagnetic interference signals between the transmitter and the receiver. Common emi cancellation circuits can be divided into passive circuits and active circuits. The passive circuit has high linearity when electromagnetic interference signals are counteracted, and the influence on the performance of the receiver is small. The main disadvantage is that the size and power consumption are too large to be integrated in a large-capacity CMOS. The active circuit has more flexibility and smaller occupied area, and can be easily integrated in batch CMOS. However, receiver performance may be degraded due to noise and distortion of the active devices. There are several different options for the location of the emi cancellation circuit in the receiver chain. Such as directly after the antenna, after a Low Noise Amplifier (LNA), after baseband down conversion. These solutions have respective advantages and disadvantages: close to the antenna can reduce the linearity requirements and thus reduce power consumption, but at the same time also increases the Noise Figure (NF), compared to a connection close to the baseband which has little effect on the NF, but before the cancellation point all modules need a high linearity to process the received signal and the overflow without compression, which means a higher power consumption. It is more challenging than the way that the vanishing point is behind the rf antenna.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides a method for eliminating a strong electromagnetic interference signal leaked by a transmitter, which is characterized in that a signal on a receiving link is associated with a sampling signal of a transmitting signal based on the known condition of the transmitting signal at a receiving end, then the delay of the sampling signal is adjusted to match the delay of the leaked electromagnetic interference signal, then the overflow is cancelled by using the superposition result of the two signals, and the electromagnetic interference is cancelled after a receiving antenna and before a low-noise amplifier.
A method for eliminating strong electromagnetic interference signals leaked by a transmitter specifically comprises the following steps:
step one, receiving and transmitting by using a receiving antennaObtaining a signal I with interference from a signal transmitted by a transmitter, and amplifying the signal I into an input signal I through an amplifier 1 。
Step two, directly coupling the output end of the transmitter by using a coupler to obtain a sampling signal I 2 Then sampling the signal I 2 Are decomposed into orthogonal signals with equal amplitude and 90-degree phase difference.
Step three, respectively inputting the two paths of orthogonal signals obtained in the step two into an adjustable gain amplifier to obtain A I And A Q Then, the signals are superposed through an adder to obtain a reference signal I 3 Wherein the reference signal I 3 Amplitude of
Phase I 3p ＝arctan(A Q /A I )。
Step four, reference signal I 3 And an input signal I 1 The feedback signal I is obtained by the superposition of an adder 4 . A feedback signal I 4 Input into the integrator.
Step five, continuously adjusting the output of the adjustable gain amplifier so as to change the reference signal I 3 Until the output of the integrator is 0, a cancellation signal I with the same amplitude and the opposite phase as the interference signal is obtained 30 。
Step six, the cancellation signal I obtained in the step five is used 30 And an input signal I 1 And after the signals are superposed by the adder, an output signal P is obtained and is input to a low noise amplifier of the receiver, so that the elimination of the electromagnetic interference signal is completed.
The invention has the following beneficial effects:
1. the electromagnetic interference signals are offset at the front end of the low-noise amplifier and the rear end of the receiving antenna in the whole receiver link, so that the saturation of the rear end circuit can be avoided.
2. And a negative feedback closed loop is designed, the correlation between the reference signal and the interference signal is judged through the integral result of the feedback signal after superposition, the calculation is simple, the amplitude and the phase of the reference signal can be adjusted in a self-adaptive manner, and the cancellation of the interference signal is realized.
Drawings
FIG. 1 is a schematic diagram of interference signal cancellation according to the present method;
FIG. 2 is a flow chart of reference signal adjustment in the present method.
Detailed Description
The invention is further explained below with reference to the drawings;
as shown in fig. 1, a method for eliminating a strong electromagnetic interference signal leaked by a transmitter specifically includes the following steps:
step one, receiving a signal transmitted by a transmitter by using a receiving antenna to obtain a signal I with interference, and amplifying the signal I into an input signal I through an amplifier 1 。
Step two, directly coupling the output end of the transmitter by using a coupler to obtain a sampling signal I 2 Because of the sampling signal I 2 Is directly coupled from the transmitter end of the transmitter, thus sampling the signal I 2 Is known as to amplitude and phase. Then sampling the signal I 2 Are decomposed into orthogonal signals with equal amplitude and 90-degree phase difference.
Step three, respectively inputting the two paths of orthogonal signals obtained in the step two into an adjustable gain amplifier to obtain A I And A Q Then, the signals are superposed through an adder to obtain a reference signal I 3 Wherein the reference signal I 3 Amplitude of
Phase I 3p ＝arctan(A Q /A I )。
Step four, reference signal I 3 And an input signal I 1 The feedback signal I is obtained by adding the adder 4 . A feedback signal I 4 Input into the integrator.
Step five, as shown in fig. 2, continuously adjusting the output of the adjustable gain amplifier, thereby changing the reference signal I 3 Until the input of the integrator is constant in the feedback loop and does not change any more, at the moment, the output of the integrator is 0, the negative feedback regulation is finished, and the amplitude value of the interference signal is obtainedEqual and opposite phase cancellation signal I 30 。
Step six, the cancellation signal I obtained in the step five is used 30 And an input signal I 1 And after the signals are superposed by the adder, an output signal P is obtained and is input to a low noise amplifier of the receiver, so that the elimination of the electromagnetic interference signal is completed.
Claims (3)
1. A method for eliminating strong electromagnetic interference signals leaked by a transmitter is characterized by comprising the following steps: the method comprises the following steps:
step one, a receiving antenna receives a signal I with interference, and an input signal I with interference is obtained after the signal I is amplified by an amplifier 1 ；
Step two, directly coupling the output end of the transmitter by using a coupler to obtain a sampling signal I 2 Then sampling the signal I 2 Decomposing the signals into two paths of orthogonal signals with equal amplitude and 90-degree phase difference;
step three, respectively inputting the two paths of orthogonal signals obtained in the step two into an adjustable gain amplifier to obtain A I And A Q And after superposition, obtaining a reference signal I 3 ；
Step four, reference signal I 3 And an input signal I 1 Superposing to obtain a feedback signal I 4 (ii) a A feedback signal I 4 Inputting into an integrator;
step five, adjusting the reference signal I 3 Until the output of the integrator is 0, a cancellation signal I with the same amplitude and the opposite phase as the interference signal is obtained 30 ；
Step six, the cancellation signal I obtained in the step five is used 30 And an input signal I 1 And after superposition, obtaining an output signal P, and inputting the output signal P into a low noise amplifier of the receiver to complete the elimination of the electromagnetic interference signal.
2. A method for canceling strong electromagnetic interference signals leaked by a transmitter according to claim 1, wherein: by varying the gain factor of the adjustable gain amplifier, varying A I And A Q Is largeSmall so as to change the reference signal I 3 Magnitude and phase of.
3. A method for canceling a strong electromagnetic interference signal leaked by a transmitter according to claim 1 or 2, wherein: wherein the reference signal I 3 Amplitude of
Phase I 3p ＝arctan(A Q /A I )。
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111144835.0A CN113938147B (en) | 2021-09-28 | 2021-09-28 | Method for eliminating strong electromagnetic interference signal leaked by transmitter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111144835.0A CN113938147B (en) | 2021-09-28 | 2021-09-28 | Method for eliminating strong electromagnetic interference signal leaked by transmitter |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113938147A CN113938147A (en) | 2022-01-14 |
| CN113938147B true CN113938147B (en) | 2022-10-21 |
Family
ID=79277262
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111144835.0A Active CN113938147B (en) | 2021-09-28 | 2021-09-28 | Method for eliminating strong electromagnetic interference signal leaked by transmitter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113938147B (en) |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6714775B1 (en) * | 2000-02-24 | 2004-03-30 | Veridian Engineering, Inc. | Interference canceller |
| CN101420246A (en) * | 2008-11-21 | 2009-04-29 | 华为技术有限公司 | Method, apparatus and transceiver for counteracting transmission interference by the transceiver |
| EP2568638A1 (en) * | 2011-09-09 | 2013-03-13 | Telefonaktiebolaget L M Ericsson (publ) | Device and method for handling interference at a receiver by activating interference cancellation according to the amount of most interfering neighbouring cells |
| CN103106418A (en) * | 2011-11-15 | 2013-05-15 | 无锡旗连电子科技有限公司 | Radio frequency identification reader-writer |
| CN103226720A (en) * | 2013-05-08 | 2013-07-31 | 岳流锋 | Carrier cancellation method for ultra-high frequency electronic tag reader-writer |
| CN106125052A (en) * | 2016-06-23 | 2016-11-16 | 复旦大学 | The removing method of a kind of Modulation Continuous Wave Radar modulation leakage and system |
| CN106452608A (en) * | 2016-10-31 | 2017-02-22 | 天津大学 | Radio-frequency transceiver being achieved by adopting notching filter and applied in wireless body local area network |
| CN107517068A (en) * | 2017-07-27 | 2017-12-26 | 湖北工业大学 | Co-located Interference Suppression System and method a kind of while that eliminate two interference |
-
2021
- 2021-09-28 CN CN202111144835.0A patent/CN113938147B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6714775B1 (en) * | 2000-02-24 | 2004-03-30 | Veridian Engineering, Inc. | Interference canceller |
| CN101420246A (en) * | 2008-11-21 | 2009-04-29 | 华为技术有限公司 | Method, apparatus and transceiver for counteracting transmission interference by the transceiver |
| EP2568638A1 (en) * | 2011-09-09 | 2013-03-13 | Telefonaktiebolaget L M Ericsson (publ) | Device and method for handling interference at a receiver by activating interference cancellation according to the amount of most interfering neighbouring cells |
| CN103106418A (en) * | 2011-11-15 | 2013-05-15 | 无锡旗连电子科技有限公司 | Radio frequency identification reader-writer |
| CN103226720A (en) * | 2013-05-08 | 2013-07-31 | 岳流锋 | Carrier cancellation method for ultra-high frequency electronic tag reader-writer |
| CN106125052A (en) * | 2016-06-23 | 2016-11-16 | 复旦大学 | The removing method of a kind of Modulation Continuous Wave Radar modulation leakage and system |
| CN106452608A (en) * | 2016-10-31 | 2017-02-22 | 天津大学 | Radio-frequency transceiver being achieved by adopting notching filter and applied in wireless body local area network |
| CN107517068A (en) * | 2017-07-27 | 2017-12-26 | 湖北工业大学 | Co-located Interference Suppression System and method a kind of while that eliminate two interference |
Non-Patent Citations (3)
| Title |
|---|
| Adaptive Interference Cancellation System with Different Correlation Control Methods;Yunhao Jiang等;《2009 International Conference on Intelligent Human-Machine Systems and Cybernetics》;20090827;全文 * |
| VCA610在水声模拟信号调理机中的应用;王春海等;《声学技术》;20071215(第06期);全文 * |
| 消除直流分量影响和谐波干扰的并网同步方法;党克 等;《电子测量与仪器学报》;20161031;全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113938147A (en) | 2022-01-14 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US8036606B2 (en) | Method and apparatus for interference cancellation | |
| US9450623B2 (en) | Noise canceler for use in a transceiver | |
| WO2016050062A1 (en) | Passive inter-modulation (pim) interference cancellation method for radio frequency module and relevant apparatus | |
| US9444411B2 (en) | RF power amplifier with total radiated power stabilization | |
| RU2531262C2 (en) | Circuit and method for interference reduction | |
| US10079702B2 (en) | Front-end module and coupling compensation for closed-loop digital pre-distortion system | |
| US20040106381A1 (en) | Transmit signal cancellation in wireless receivers | |
| US20080207256A1 (en) | Concurrent impedance matching of a wireless transceiver | |
| CN112235055B (en) | Heterodyne self-adaptive interference cancellation device based on digital Hilbert transform | |
| CN111585594B (en) | Interference cancellation device and method based on cascade digital control method | |
| US20120094617A1 (en) | Module for mobile communication terminal, and mobile communication terminal | |
| CN109845118A (en) | A kind of tower top device and passive intermodulation removing method | |
| CN103166666A (en) | Radio transceiver with im2 mitigation | |
| US20090017770A1 (en) | Noise cancellation system for transceivers | |
| US8638836B2 (en) | Transmitter signal injection compensation | |
| CN113938147B (en) | Method for eliminating strong electromagnetic interference signal leaked by transmitter | |
| CN216313076U (en) | Circuit for eliminating electromagnetic interference signal leaked by transmitter | |
| US8295791B2 (en) | RF front-end circuit | |
| US20210044259A1 (en) | Radio Frequency Receiver, Radio Frequency Transmitter, and Communications Device | |
| CN108418601B (en) | Carrier cancellation system | |
| CN103684492A (en) | Radio frequency signal sampling device, a reception machine and a base station. | |
| US8441322B1 (en) | Broadband linearization by elimination of harmonics and intermodulation in amplifiers | |
| CN115276568B (en) | Miniaturized filtering low-noise amplifier and receiver | |
| US20240171430A1 (en) | Interference cancellation in a multi-radio system and apparatus for cancellation | |
| WO2023087200A1 (en) | Signal processing apparatus and communication device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |