CN103986482B - A kind of passive intermodulation disturbance restraining method based on adaptive-filtering - Google Patents

A kind of passive intermodulation disturbance restraining method based on adaptive-filtering Download PDF

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CN103986482B
CN103986482B CN201410226937.0A CN201410226937A CN103986482B CN 103986482 B CN103986482 B CN 103986482B CN 201410226937 A CN201410226937 A CN 201410226937A CN 103986482 B CN103986482 B CN 103986482B
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pim
signal
passive intermodulation
adaptive
interference
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CN103986482A (en
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田露
王帅
卜祥元
安建平
曹文慧
高晓铮
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Beijing Institute of Technology BIT
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Abstract

The present invention relates to passive intermodulation disturbance restraining method in a kind of full duplex communication system, particularly relate to a kind of passive intermodulation interference mitigation technology based on adaptive-filtering, belong to wireless communication signals processing technology field, especially belong to full duplex communication system technical field.The present invention establishes the simplified model of passive non-linear device, is intended to carry out AF panel with the method for Digital Signal Processing.Adaptive filter algorithm as one effectively and be easy to hard-wired algorithm for estimating and be used, to realize passive intermodulation interference offseting in intermediate-freuqncy signal.Simulation result shows, this invention can effectively suppress passive intermodulation to disturb, and realizes certain signal interference ratio gain.The method is simple, and computation complexity is low, and Resources Consumption is little, is easy to hardware implementing; The method stable performance, system suitability is strong, and real-time is good; The method can effectively suppress passive intermodulation to disturb, and realizes higher Signal to Interference plus Noise Ratio gain.

Description

A kind of passive intermodulation disturbance restraining method based on adaptive-filtering
Technical field
The present invention relates to passive intermodulation disturbance restraining method in a kind of full duplex communication system, particularly relate to a kind of passive intermodulation interference mitigation technology based on adaptive-filtering, belong to wireless communication signals processing technology field, especially belong to full duplex communication system technical field.
Background technology
Passive intermodulation (PIM) refers to the gang's product produced through passive device nonlinear effect by two or more frequency contents, and its frequency is the linear combination of fundamental frequency.When namely forming interference in the passband that linear combination product falls into communication control processor.Passive intermodulation is extensively present in communication system, is the phenomenon being difficult to eliminate completely, is just found as far back as the seventies in last century.Along with the raising of communication requirement, high power and high sensitivity become developing direction.Antenna size needed for communication is increasing, is forced to adopt transmitting-receiving communal technique by platform restriction.In the antenna transmit-receive sharing communication system that duplexer isolation is low, passive intermodulation product more easily enters frequency acceptance band and forms interference, and cannot by the mode of frequency domain filtering by its filtering.For Mobile communication direct base station, the descending high-power passive intermodulation product transmitted can fall in uplink receiving frequency band, impacts communication system.
The passive intermodulation interference in narrow-band mobile communication system can be reduced by band plan and frequency pattern design.And for still there is the problem of passive intermodulation interference in wide-band mobile communication system.
In May, 2011, the patent of invention of Ericsson's application " DynamicCancellationofPassiveIntermodulationInterference " by name, proposes the digital signal processing solution of PIM interference cancellation.The method can be offset PIM interference signal to a certain extent, but its maximum shortcoming is, needs periodically or unexpectedly interrupt communication, carries out parameter Estimation, not strong to ripe satellite communication system adaptability.
In the same year, refer to a kind of simulation in the paper of by name " SuccessiveRegenerationandAdaptiveCancellationofHigherOrd erIntermodulationProductsinRFReceivers " that " IEEETRANSACTIONSONMICROWAVETHEORYANDTECHNIQUES " magazine is delivered and rebuild the treating method be combined with digital signal and carry out PIM and offset.Its basic thought is, by simulating second order inter-modulation and low order odd-order intermodulation, to estimate high order intermodulation component, and then estimating each rank intermodulation coefficient, carrying out interference cancellation.The method needs extra hardware supports, and its nonlinear characteristic and coefficient estimate all there is larger uncertainty, and is not suitable for practical application.
In one section that VTC meeting in 2008 is delivered " AStochasticGradientLMSAlgorithmfordigitalCompensationofT xLeakageinZero-IF-Receivers " by name, illustrating in detail the principle adopting the method for adaptive-filtering to carry out PIM interference, and give performance optimization curve.But its model too simplifies, and only considers second order inter-modulation.
Summary of the invention
The object of the invention is the passive intermodulation interference problem solving full duplex communication system, propose a kind of passive intermodulation disturbance restraining method based on adaptive-filtering, under the prerequisite not increasing additional hardware equipment, realize the suppression real-time of passive intermodulation interference adaptively.
Based on a passive intermodulation disturbance restraining method for adaptive-filtering, implementation step is as follows:
Step 1, utilize and to transmit feature, as the information such as number of carriers, frequency, analyze each rank PIM product property, as frequency, bandwidth etc.
Step 2, determine the effective interference components of PIM product according to receiver, namely calculate the PIM signal fallen in frequency acceptance band.
Step 3, utilize the high-power up-conversion that transmits before intermediate frequency or the intermediate-freuqncy signal of baseband signal to the effective interference components of PIM rebuild.
Reconstruction model is made up of memoryless nonlinear system and the cascade of memory linear system, and the delay transport of corresponding intermodulation process and intermodulation product is coupled with amplitude respectively.Memory linear system generally selects transversal filter, and memoryless nonlinear system often selects power series model.
Step 4, the radiofrequency signal received receiving terminal, carry out down-conversion and sample, obtaining digital intermediate frequency signal.
Step 5, by the intermediate-freuqncy signal of receiving terminal with rebuild after PIM interference signal component input adaptive filter.According to adaptive filtration theory, take constrained minimum output energy as criterion, obtain the optimal value of filter tap weights and each rank PIM product weight.Iterative process can adopt least mean square algorithm (LMS) or recursive least squares (RLS), Automatic adjusument model parameter, realizes offseting real-time.Passive intermodulation disturbance restraining method principle as shown in Figure 1.Now, the intermediate-freuqncy signal be after PIM AF panel is outputed signal.
Based on a passive intermodulation disturbance restraining method for adaptive-filtering, it is characterized in that performing step is as follows:
Step 1) utilize the feature that transmits, analyze the characteristic of each rank PIM product;
Step 2) according to receiver determining step 1) in effective interference components of PIM product, namely calculate the PIM signal fallen in frequency acceptance band;
Step 3) utilize the transmit intermediate frequency before up-conversion or baseband signal effectively to disturb intermediate-freuqncy signal component to rebuild to PIM;
Reconstruction model is made up of memoryless nonlinear system and the cascade of memory linear system, and the delay transport of corresponding intermodulation process and intermodulation product is coupled with amplitude respectively;
Step 4) radiofrequency signal that receiving terminal is received, carry out down-conversion and sample, obtaining digital intermediate frequency signal;
Step 5) by step 4) digital intermediate frequency signal that obtains and step 3) PIM after the reconstruction that obtains effectively disturbs intermediate-freuqncy signal component input adaptive filter; According to adaptive filtration theory, take constrained minimum output energy as criterion, obtain the optimal value of filter tap weights and each rank PIM product weight, sef-adapting filter can Automatic adjusument model parameter, realize offseting real-time, after offseting, output signal the intermediate-freuqncy signal be after PIM AF panel.
Beneficial effect
1. the method is simple, and computation complexity is low, and Resources Consumption is little, is easy to hardware implementing;
2. the method stable performance, system suitability is strong, and real-time is good;
3. the method can effectively suppress passive intermodulation to disturb, and realizes higher Signal to Interference plus Noise Ratio gain.
4. the present invention establishes the simplified model of passive non-linear device, is intended to carry out AF panel with the method for Digital Signal Processing.Adaptive filter algorithm as one effectively and be easy to hard-wired algorithm for estimating and be used, to realize passive intermodulation interference offseting in intermediate-freuqncy signal.Simulation result shows, this invention can effectively suppress passive intermodulation to disturb, and realizes certain signal interference ratio gain.
Accompanying drawing explanation
Fig. 1 is passive intermodulation disturbance restraining method schematic diagram of the present invention;
Fig. 2 is the radio-frequency power spectrum density transmitted in embodiment, and abscissa is normalized digital signal frequency, and ordinate is power spectral density;
Fig. 3 is the radio-frequency power spectrum density by the PIM produced that transmits in embodiment, and abscissa is normalized digital signal frequency, and ordinate is power spectral density;
Fig. 4 is the schematic diagram that employing adaptive-filtering in embodiment carries out passive intermodulation AF panel;
Fig. 5 is time domain comparison diagram before and after the interference cancellation that suppresses of the PIM interference signal being 0dB to signal interference ratio in embodiment, and abscissa is sampled point sequence number, and ordinate is signal amplitude;
Fig. 6 suppresses the PIM interference signal of (signal to noise ratio snr=-12dB) under low signal-to-noise ratio in embodiment, and obtain the simulation curve figure that the error rate changes with jamming-to-signal ratio, abscissa is signal interference ratio, and ordinate is the error rate.
Embodiment
In order to object and the advantage of the inventive method are described better, below in conjunction with the accompanying drawing in embodiment, clear, complete description is carried out to the technical scheme in the embodiment of the present invention, obviously, described embodiment is only the present invention's part embodiment, instead of whole embodiments.Based on the embodiment in the present invention, those of ordinary skill in the art, not making the every other embodiment obtained under creative work prerequisite, belong to protection scope of the present invention.
Embodiment
To adopt the communication satellite coverage of S-band, the present invention's " a kind of passive intermodulation disturbance restraining method based on adaptive-filtering " is utilized to realize passive intermodulation AF panel, as shown in Figure 1.
Step 1, utilize and to transmit feature, analyze each rank PIM product property;
The known repeater transmitting terminal parameter feature that namely transmits is as follows:
(1) transmit centre frequency: S-band transmit frequency range is 2030MHz ~ 2060MHz.For two carrier wave, choose two carrier transmission signal centre frequency and be respectively, f 1=2030MHz, f 2=2060MHz;
(2) output symbol speed is modulated: 2.5Mbaud;
(3) modulation system: BPSK;
(4) channel coding method: nothing;
(5) shaping window function is modulated: raise roof cosine, α=0.35.
The power spectral density transmitted as shown in Figure 2; Utilize the feature that transmits to carry out analogue simulation and obtain the power spectral density of PIM product as shown in Figure 3;
Step 2, determine the effective interference components of PIM product according to receiver, namely calculate the PIM signal fallen in frequency acceptance band.
The frequency range of known repeater receiving terminal is 1840MHz ~ 1870MHz.Wherein, setting one group of Received signal strength centre frequency is f uP=1849.95MHz.By analysis, 13 rank PIM fall into frequency acceptance band, 7f 1-6f 2=1850MHz.Adopt traversal or fast search way the PIM product within 150 rank falling into frequency acceptance band can be calculated, have 20 PIM products and fall in frequency acceptance band and form interference, corresponding intermodulation exponent number is as shown in the table.
Table 1 passive intermodulation order analysis
As can be seen from Table 1, except 13 rank PIM products, the PIM product falling into frequency acceptance band is Ultra-High Order PIM, and the part that its power spectral density is falling into frequency acceptance band is very mild, and amplitude is small, can be similar to and be considered as white noise after multinomial superposition.Therefore, only consider the suppression of 13 rank PIM products when carrying out AF panel, although we have the ability Ultra-High Order PIM product to eliminate.
Step 3, the transmit intermediate frequency before up-conversion or the intermediate-freuqncy signal of baseband signal to the effective interference components of PIM is utilized to rebuild.
Research shows, in the process suppressing n rank passive intermodulation interference components, except the n power item that consideration transmits, also needs to consider that all odd numbers higher than n (when n is odd number) power item is on the impact of n rank passive intermodulation interference components.That is, n power item can not only produce n rank passive intermodulation component, also can produce the passive intermodulation component such as n-2 rank, n-4 rank.Therefore, when offseting n rank passive intermodulation component, not only needing the n power item considering to transmit, also needing to consider the more high math power item such as n+2, n+4.If not for the linear system of our research, when analyzing the passive intermodulation interference of n rank, getting n+2 power item and just can express this rank intermodulation component comparatively accurately, thus simplifying computational process.In the present embodiment, 13 power items and 15 power items are considered.The memoryless non-linear partial of reconstruction model can be expressed as,
f(x)＝a 13x 13+a 15x 15(1)
Wherein, a 13and a 15be respectively x in memoryless non-linear f (x) 13and x 15coefficient.Because this power series model cannot describe the memory effect between input and output, for setting up the PIM model of obeying the PIM characteristic of channel, needing cascade one Linear Memory system, embodying the delay between transmitting-receiving, amplitude coupled relation.In the present embodiment, this Linear Memory system is digital transversal filter.Suppose [w 0, w 1..., w m-1] be filter tap weights, available w [k] (k=0,1 ... M-1) represent, M is filter tap exponent number.PIM after then rebuilding disturbs digital signal to be expressed as,
s PIM [ k ] = w [ k ] ⊗ Σ i = 1 N α i s PIMi [ k ] - - - ( 2 )
Wherein, s pIMi[k] be not for considering the PIM interference signal reference items of memory effect, α ifor its amplitude, s pIMi[k] is derived by formula (1) and draws, N is PIM interference signal reference items number, in the present embodiment, and N=3,
s PIM 1 [ k ] = R 1 7 ( k ) R 2 6 ( k ) cos [ 2 πk * ( 7 f 1 - 6 f 2 - f LO ) / f s ]
s PIM 2 [ k ] = R 1 9 ( k ) R 2 6 ( k ) cos [ 2 πk * ( 7 f 1 - 6 f 2 - f LO ) / f s ] - - - ( 3 )
s PIM 3 [ k ] = R 1 7 ( k ) R 2 8 ( k ) cos [ 2 πk * ( 7 f 1 - 6 f 2 - f LO ) / f s ]
Wherein, R 1(k) and R 1k () is the digital sample of the baseband signal of transmitting, sample frequency is f s, f lOfor the local frequency of low-converter.
Step 4, the radiofrequency signal received receiving terminal, carry out down-conversion and sample, and obtains digital intermediate frequency signal s uL[k].
Step 5, by the intermediate-freuqncy signal s of receiving terminal uL[k] and the PIM interference signal component s after rebuilding pIM[k] input adaptive filter, as shown in Figure 4.Obtaining system output errors is thus
e[k]＝s UL[k]-s PIM[k](4)
Make mean square error J [k]=E{e [k] e [k] *minimum, can s be determined pIMcomprise unknown parameter in [k], simultaneously adjust value of consult volume in real time according to the change of input signal, the principle of Here it is sef-adapting filter.For ensureing to ask uniqueness of solution, make a 1=1, calculate the Amplitude Ratio of every passive intermodulation interference components.
J[k]＝E{e[k]e *[k]}＝E{(s UL[k]-s PIM[k])(s UL[k]-s PIM[k]) *}(5)
For trying to achieve E{e [k] e [k] *minimum value, need meet
▿ E { e [ k ] e * [ k ] } = ( ∂ E { e [ k ] e * [ k ] } ∂ w , ∂ E { e [ k ] e * [ k ] } ∂ α ) = 0 - - - ( 6 )
Wherein, w=[w 0, w 1..., w m-1], α=[α 1, α 2..., α n].
Solve (6) formula, Newton method, steepest descent method or conjugate gradient method can be adopted, namely obtain the optimal value of filter tap weights and each rank PIM product weight.Iterative process can adopt least mean square algorithm (LMS) or recursive least squares (RLS) in conjunction with coordinate descending method, Automatic adjusument model parameter.Adopt adaptive filter algorithm to optimal value, good tracking performance can be had by rapid convergence very much simultaneously, suppress to realize PIM interference signal real-time fast.
Adopt the disturbance restraining method in the present invention's " a kind of passive intermodulation disturbance restraining method based on adaptive-filtering ", the PIM interference signal that signal interference ratio under the present embodiment environment is 0dB is suppressed, time domain comparison diagram before and after the interference cancellation obtaining Fig. 5, the signal recovered after PIM interference cancellation almost overlaps with the signal disturbed without PIM, and this algorithm can effectively eliminate PIM interference signal.
Adopt the disturbance restraining method in the present invention's " a kind of passive intermodulation disturbance restraining method based on adaptive-filtering ", PIM interference signal in (SNR=-12dB) the present embodiment under low signal-to-noise ratio is suppressed, obtains the simulation curve that the error rate shown in Fig. 6 changes with jamming-to-signal ratio.Ber curve after PIM interference cancellation and theoretical curve degree of approximation high, this algorithm can effectively suppress passive intermodulation to disturb as seen, increases substantially anti-PIM interference performance.
The above is preferred embodiment of the present invention, and the present invention should not be confined to the content disclosed in this embodiment and accompanying drawing.Every do not depart from spirit disclosed in this invention under the equivalence that completes or amendment, all fall into the scope of protection of the invention.

Claims (4)

1., based on a passive intermodulation disturbance restraining method for adaptive-filtering, it is characterized in that performing step is as follows:
Step 1) utilize the feature that transmits, analyze the characteristic of each rank passive intermodulation (PIM) product;
Step 2) according to receiver determining step 1) in effective interference components of PIM product, namely calculate the PIM signal fallen in frequency acceptance band;
Step 3) utilize the transmit intermediate frequency before up-conversion or baseband signal effectively to disturb intermediate-freuqncy signal component to rebuild to PIM; The PIM rebuild effectively disturbs the exponent number of intermediate-freuqncy signal component and step 2) in fall into the exponent number of the PIM signal in frequency acceptance band identical;
Reconstruction model is made up of memoryless nonlinear system and the cascade of memory linear system, and the delay transport of corresponding intermodulation process and intermodulation product is coupled with amplitude respectively;
Step 4) radiofrequency signal that receiving terminal is received, carry out down-conversion and sample, obtaining digital intermediate frequency signal;
Step 5) by step 4) digital intermediate frequency signal that obtains and step 3) PIM after the reconstruction that obtains effectively disturbs intermediate-freuqncy signal component input adaptive filter; According to adaptive filtration theory, take constrained minimum output energy as criterion, obtain the optimal value of filter tap weights and each rank PIM product weight, sef-adapting filter can Automatic adjusument model parameter, realize offseting real-time, after offseting, output signal the intermediate-freuqncy signal be after PIM AF panel.
2. a kind of passive intermodulation disturbance restraining method based on adaptive-filtering according to claim 1, is characterized in that: memory linear system selects transversal filter.
3. a kind of passive intermodulation disturbance restraining method based on adaptive-filtering according to claim 1, is characterized in that: memoryless nonlinear system selects power series model.
4. a kind of passive intermodulation disturbance restraining method based on adaptive-filtering according to claim 1, is characterized in that: the method obtaining the optimal value of filter tap weights and each rank PIM product weight is: least mean square algorithm or recursive least squares.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2018121507A1 (en) * 2016-12-29 2018-07-05 华为技术有限公司 Passive intermodulation suppression method and passive intermodulation suppression system

Families Citing this family (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104283580B (en) * 2014-09-30 2016-09-28 上海华为技术有限公司 The passive intermodulation PIM interference cancellation method of radio-frequency module and relevant apparatus
US9923658B2 (en) * 2014-12-23 2018-03-20 Intel Corporation Interference cancelation
WO2017035742A1 (en) * 2015-08-31 2017-03-09 华为技术有限公司 Scheduling method and device
CN105049067B (en) * 2015-08-31 2017-09-29 北京理工大学 A kind of passive intermodulation interference cancellation method based on pilot signal
CN105306405B (en) * 2015-09-10 2018-10-26 北京理工大学 A kind of passive intermodulation signal time delay, frequency and phase estimation device and method
US9935615B2 (en) * 2015-09-22 2018-04-03 Intel Corporation RLS-DCD adaptation hardware accelerator for interference cancellation in full-duplex wireless systems
US20170141807A1 (en) * 2015-11-12 2017-05-18 Futurewei Technologies, Inc. High Performance PIM Cancellation With Feedback
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EP3410605A1 (en) 2017-06-02 2018-12-05 Intel IP Corporation Communication device and method for radio communication
CN107271769A (en) * 2017-06-19 2017-10-20 电子科技大学 Fundamental wave cancellation techniques passive cross modulation test system and its method of testing
CN107425826B (en) * 2017-07-19 2020-12-15 广东美芝制冷设备有限公司 Adaptive filtering method, adaptive filter, and storage medium
CN107666361B (en) * 2017-09-01 2019-11-15 廊坊银河信通科技有限公司 The adaptive cancellation method and device of multicarrier passive intermodulation interference
CN108777585B (en) * 2018-02-09 2020-07-10 香港梵行科技有限公司 Device and method for self-adaptively counteracting passive intermodulation signal in wireless transceiving system
WO2020132893A1 (en) * 2018-12-25 2020-07-02 华为技术有限公司 Pim cancellation method and device
CN111465042B (en) * 2019-01-22 2022-01-14 华为技术有限公司 Scheduling method and device
CN110190920B (en) * 2019-06-10 2020-06-09 中国人民解放军陆军工程大学 Reference signal extraction method and system based on minimum mean square error cancellation algorithm
WO2021046677A1 (en) * 2019-09-09 2021-03-18 华为技术有限公司 Pim self-cancellation method and device
CN114073012B (en) * 2019-11-13 2024-04-02 Oppo广东移动通信有限公司 Reconstruction method and device of intermodulation interference signal
CN115244858A (en) * 2020-03-18 2022-10-25 瑞典爱立信有限公司 Removal of passive intermodulation in antenna systems
CN113676425A (en) * 2020-05-15 2021-11-19 北京三星通信技术研究有限公司 Method and device for eliminating passive intermodulation interference
CN112260770B (en) * 2020-10-15 2021-12-10 华南师范大学 Intermodulation interference suppression device for high-power electric contact microwave passive device
CN115549709B (en) * 2022-11-29 2023-03-24 富景慧智(北京)科技有限公司 Satellite communication system and method for inhibiting multi-channel mutual interference

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101207428A (en) * 2006-12-21 2008-06-25 京信通信技术(广州)有限公司 Method for anti-self excitation of straight amplification station system

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2012161632A1 (en) * 2011-05-20 2012-11-29 Telefonaktiebolaget L M Ericsson (Publ) Dynamic cancellation of passive intermodulation interference
US8890619B2 (en) * 2012-08-02 2014-11-18 Telefonaktiebolaget L M Ericsson (Publ) PIM compensation in a receiver

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101207428A (en) * 2006-12-21 2008-06-25 京信通信技术(广州)有限公司 Method for anti-self excitation of straight amplification station system

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
射频功放预失真技术的研究;刘俊坊;《中国优秀硕士学位论文全文数据库》;20120615;全文 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2018121507A1 (en) * 2016-12-29 2018-07-05 华为技术有限公司 Passive intermodulation suppression method and passive intermodulation suppression system

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