CN107453782A - A kind of passive intermodulation interference cancellation system and method based on the estimation of double time delays - Google Patents
A kind of passive intermodulation interference cancellation system and method based on the estimation of double time delays Download PDFInfo
- Publication number
- CN107453782A CN107453782A CN201710729053.0A CN201710729053A CN107453782A CN 107453782 A CN107453782 A CN 107453782A CN 201710729053 A CN201710729053 A CN 201710729053A CN 107453782 A CN107453782 A CN 107453782A
- Authority
- CN
- China
- Prior art keywords
- pim
- signal
- time slot
- interference
- time delay
- 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.)
- Pending
Links
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
- H04B1/38—Transceivers, i.e. devices in which transmitter and receiver form a structural unit and in which at least one part is used for functions of transmitting and receiving
- H04B1/40—Circuits
- H04B1/50—Circuits using different frequencies for the two directions of communication
- H04B1/52—Hybrid arrangements, i.e. arrangements for transition from single-path two-direction transmission to single-direction transmission on each of two paths or vice versa
- H04B1/525—Hybrid arrangements, i.e. arrangements for transition from single-path two-direction transmission to single-direction transmission on each of two paths or vice versa with means for reducing leakage of transmitter signal into the receiver
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Noise Elimination (AREA)
Abstract
A kind of passive intermodulation interference cancellation system and method based on the estimation of double time delays of the present invention, belongs to radio communication Anti-Jamming Technique field.Including cancellation system and offset method；Step is as follows：Step 1) duplexer transmitting dual carrier QPSK modulation downstream signals, then receive uplink signal；Step 2) judges whether reception signal is in pilot time slot, and judges to skip to step 3) or step 6)；Step 3) carries out PIM parameter Estimations, sets PIM model parameters；Step 4) rebuilds PIM interference signals；Step 5) carries out double time delay estimation processing, and adjustment PIM model parameters are set；Step 6) data pre-processing unit processing data transmission time slot reception signal simultaneously gives gained signal output to interference cancellation unit；Offset setting unit and PIM model parameters are set；Step 7) carries out interference cancellation；Whether step 8) terminates to determine to complete PIM interference cancellations according to this data transmission slots.The present invention, which realizes, changes sensitive, high-precision dual carrier PIM interference suppression in real time.
Description
Technical field
The present invention relates to a kind of passive intermodulation interference cancellation system and method based on the estimation of double time delays, belong to channel radio
Signal transacting and the Anti-Jamming Technique field of letter, satellite communication and GCS Ground Communication System.
Background technology
Passive intermodulation (Passive Intermodulation, abbreviation PIM) refers to the letter of two or more frequency contents
Number by produced when passive device (such as duplexer, isolator, coaxial cable, connector, antenna, load) except harmonic wave in addition to it is new frequently
A kind of phenomenon of rate composition.Caused new frequency is the linear combination of fundamental frequency, and communication control processor is fallen into when newly producing frequency
Passband in i.e. formed interference.
With radio communication, the continuous development of satellite communication, antenna size needed for communication becomes big, by therefrom using receipts
Send out common technology.Duplexer isolation is low in antenna transmit-receive sharing system, and passive intermodulation product, which is easily accessible, to be received frequency band and formed
Interference, and be difficult to be filtered out by the method for frequency domain filtering, communication system can be impacted.
To realize PIM interference cancellations, Ericsson, Beijing Institute of Technology and Huawei Company applied for Patents,
The PIM interference cancellation methods based on signal transacting are proposed, but such method specific aim is poor, only considered no time delay PIM and does
That disturbs offsets method, it is impossible to is well adapted for the time-varying characteristics of PIM signals.
Wherein, the patent application that patent one proposes for Ericsson, number of patent application：US8855175B2, it is entitled
" Low Complexity All-Digital PIM Compensator ", it is main to propose adaptive PI M interference cancellation methods, should
Method needs to determine PIM number of parameters by test signal, so as to obtain PIM model parameters using parameter estimation model, estimates
Go out PIM interference signals.This method only considers the ART network of preferable PIM interference, consumption resource is big, processing procedure is cumbersome and
It is difficult to restrain for a long time in the estimation of time-varying PIM interference.
The patent application that patent two proposes for Beijing Institute of Technology, number of patent application：It is 201410226937.0 entitled
" a kind of passive intermodulation disturbance restraining method based on adaptive-filtering ", mainly propose the PIM interference suppressions based on adaptive-filtering
Method processed, using each rank PIM product properties of transmission signal signature analysis, by power series Model Reconstruction PIM signals, finally use
The method of adaptive-filtering is realized and offseted.This method relies on power series Model Reconstruction PIM signals, but does not account for carrier wave time delay and make
Into PIM time-varying characteristics, offset precision deficiency.
The patent application that patent three proposes for Huawei Company, number of patent application：201410522019.2 entitled " radio frequency
The passive intermodulation PIM interference cancellation methods and relevant apparatus of module ", it is main to propose to produce using the nonlinear transformation of transmission signal
Nonlinear parameter, offseting signal is produced by transmission signal and nonlinear parameter PIM interference signals are offseted, but passed through
The non-linear reconstruction mode that convolution obtains is single, it is difficult to is effectively offseted for the PIM interference under complex environment.
The patent application that patent four proposes for Beijing Institute of Technology, number of patent application：It is 201510547503.5 entitled
" a kind of passive intermodulation interference cancellation method based on pilot tone ", mainly proposes the passive intermodulation interference cancellation side based on pilot signal
Method, the channel impulse response that PIM nonlinear models shape parameter and PIM signals couple is estimated by pilot tone, it is non-by the PIM estimated
Linear dimensions is estimated PIM interference signals and offseted.This method relies on the priori of channel, and to channel circumstance requirement
Height preferably offsets precision, poor practicability, it is necessary to can be only achieved under high signal interference ratio.
This patent offsets the technological deficiency that method is difficult to offset time-varying PIM for existing PIM, is directed to proposing that one kind is directed to
Changing for dual carrier PIM time-varying interference is sensitive, the high passive intermodulation interference cancellation system based on the estimation of double time delays of precision of prediction
With method.
The content of the invention
It is an object of the invention to for passive intermodulation interference be present in existing wireless communications, satellite communication system, cause
Passive intermodulation time delay overestimate and passive intermodulation interference cancellation effect it is poor the defects of, it is proposed that one kind is based on double time delays
The passive intermodulation interference cancellation system and method for estimation.
A kind of passive intermodulation interference cancellation system and method based on the estimation of double time delays, including it is a kind of based on double time delays estimations
Passive intermodulation interference cancellation system, abbreviation cancellation system；With a kind of passive intermodulation interference cancellation side based on the estimation of double time delays
Method, referred to as offset method；
Wherein, cancellation system is the signal processing of the communication system of antenna transmit-receive sharing；Antenna transmit-receive sharing leads to
Letter system includes duplexer, isolator, coaxial cable, connector, antenna, the passive device based on load, cause it is passive mutually
Cadre enrolled among workers disturbs；
Cancellation system mainly includes receiving pretreatment module, PIM reconstructions module, double time delay estimation modules and interference cancellation
Module；
Wherein, receiving pretreatment module includes PIM parameter estimation units and data pre-processing unit；PIM rebuilds module bag
Include PIM parameter set units and PIM reconstruction units；Double time delay estimation modules include double time delay estimation units；Interference cancellation module
Including offseting setting unit and interference cancellation unit；
The annexation of each module of cancellation system is：
Pretreatment module is received with PIM reconstructions module, double time delay estimation modules and interference cancellation module to be connected；PIM weights
Modeling block is connected with receiving pretreatment module, double time delay estimation modules and interference cancellation module；Double time delay estimation modules are with connecing
Receive pretreatment module and PIM rebuilds module and is connected；Interference cancellation module rebuilds module phase with receiving pretreatment module and PIM
Even；
The annexation of cancellation system each unit is：
PIM parameter estimation units and data pre-processing unit, PIM parameter set units and offset setting unit and be connected；
Data pre-processing unit is connected with PIM parameter estimation units, double time delay estimation units and interference cancellation unit；PIM parameters are set
Unit is put with PIM parameter estimation units, double time delay estimation units and PIM reconstruction units to be connected；PIM reconstruction units are joined with PIM
Number setting unit, double time delay estimation units and interference cancellation unit are connected；Double time delay estimation units and data pre-processing unit,
PIM parameter set units and PIM reconstruction units are connected；Offset setting unit and PIM parameter estimation units and interference cancellation
Unit is connected；Interference cancellation unit and data pre-processing unit, PIM reconstruction units and offset setting unit and be connected；
Each functions of modules of cancellation system is as follows：
The function of receiving pretreatment module is used in pilot time slot and data transmission slots reception signal, and carries out PIM
Nonlinear parameter is analyzed and Signal Pretreatment, and output pretreatment pilot time slot reception signal and pretreatment non-pilot time slot receive letter
Number；Wherein, pretreatment non-pilot time slot reception signal is also known as preprocessed data time slot reception signal；Pilot time slot will be pre-processed
Reception signal exports rebuilds module, time delay estimation module and interference cancellation module to PIM；PIM rebuilds module and receives pretreatment
The PIM nonlinear parameters of module output, PIM interference signal reconstructions are carried out using the PIM nonlinear parameters, PIM interference will be rebuild
Signal output gives double time delay estimation modules and interference cancellation module；Double time delay estimation modules receive rebuild PIM interference signals and
Pre-processing pilot time slot reception signal and carry out double time delay estimations, the double delay parameters for estimating to obtain are fed back into PIM rebuilds module,
PIM interference signals are rebuild in amendment；Interference cancellation unit receives amendment and rebuilds PIM interference signals and preprocessed data time slot reception letter
Number carry out interference cancellation；
Cancellation system each unit function is as follows：
The pilot time slot reception signal and data transmission slots reception signal that data pre-processing unit processing receives, will locate in advance
Reason pilot time slot reception signal is exported to PIM parameter set units and double time delay estimation units, when preprocessed data is transmitted
Gap reception signal, which exports, gives interference cancellation unit；PIM parameter estimation units receive pretreatment pilot time slot reception signal, will estimate
Obtained PIM nonlinear parameters, which export, gives PIM parameter set units；
For PIM parameter set units in pilot time slot, the PIM nonlinear parameters for passing through reception set PIM model parameters；In number
According to transmission time slot, dual carrier time delay and PIM time delays are received, adjustment PIM model parameters are set；PIM reconstruction units are in pilot tone
Gap, double time delay estimation units are given according to the PIM Model Reconstruction PIM interference signals of arrange parameter, and by the signal output；In data
Transmission time slot, amendment PIM interference signals are rebuild by the PIM model parameters of adjustment, and give the signal output to interference cancellation list
Member；
Double time delay estimation units receive pilot time slot reception signal and rebuild PIM interference signals, and carry out double time delays and estimate
Meter processing, the dual carrier time delay and PIM time delays that estimation is obtained export and give PIM parameter set units；
Offset the PIM model parameters that setting unit receives the output of PIM parameter estimation units, using constrained minimum output energy as
Criterion, sef-adapting filter parameter is set；Interference cancellation unit receives preprocessed data transmission time slot reception signal and reconstruction
PIM interference signals carry out interference cancellation, and the preprocessed data transmission time slot reception signal through interference cancellation is exported, and carry out follow-up
Signal transacting；
The present invention offsets method to double time slot reception signals for being disturbed containing dual carrier PIM using based on the estimation of double time delays
AF panel is carried out, double time slot reception signals include pilot time slot reception signal and data transmission slots reception signal；
The core concept for offseting method is：Step 1) duplexer transmitting dual carrier QPSK modulation downstream signals, then receive
Downlink signal；Step 2) judges whether reception signal is in pilot time slot, and judges to skip to step 3) or step 6)；Step
3) PIM parameter Estimations are carried out, PIM model parameters are set；Step 4) rebuilds PIM interference signals；Step 5) carries out double time delay estimations
Processing, adjustment PIM model parameters are set；Step 6) data pre-processing unit processing data transmission time slot reception signal and by gained
Signal output gives interference cancellation unit；Offset setting unit and PIM model parameters are set；Step 7) carries out interference cancellation；Step 8)
Whether terminate to determine to complete PIM interference cancellations according to this data transmission slots.
Method is offseted, is comprised the following steps that：
Step 1：In the communication system of antenna transmit-receive sharing, duplexer transmitting dual carrier QPSK modulation downstream signals, then
Receive uplink signal；
Wherein, downstream signal includes descending pilot frequency time slot signal and descending non-pilot time slot signal, caused by downstream signal
PIM interference signals sPIM(t) formula (1) can be expressed as：
Wherein, sD(t) it is downstream signal,Represent to each single item alsD(t)lSummed, alRepresent power level
Exponential model order l range value, i.e.,：PIM interference signals caused by downstream signal using power series model represent, wherein, it is descending
Pilot frequency time slot signal in signal, referred to as descending pilot frequency time slot signal, it is linear FM signal, also known as LFM signals；Wherein,
Descending non-pilot time slot signal is also referred to as downlink data time slot signal；
The uplink signal of reception includes upward signal, PIM interference signals and noise three parts, can use equation below
(2) represent：
sR(t)=sUP(t)+IPIM(t)*h(t)+n0(t) (2)
Wherein, sR(t) it is the uplink signal received, sUP(t) it is upward signal, n0(t) it is noise, IPIM(t) under being
PIM interference signals caused by row signal, including PIM interference signals s caused by pilot time slot and data transmission slotsPIM(t), h
(t) represent that PIM interference signals are transmitted into the coupling channel impulse response of reception, I by duplexerPIM(t) * h (t) represent duplexer
The PIM interference signals received, * represent convolution algorithm；
Step 2：Whether the uplink signal that data pre-processing unit processing step one receives, judge reception signal
In pilot time slot, determined to skip to step 3 or step 6 according to judged result, be specially：
If 2.1 reception signals are in pilot time slot, the pilot component in pilot time slot reception signal is removed, obtains pre- place
Manage pilot time slot reception signal, i.e. PIM interference signals, and this signal output is estimated to PIM parameter estimation units and double time delays
Unit is counted, and skips to step 3；
Wherein, remove pilot time slot reception signal in pilot component, especially by by pilot time slot reception signal with leading
Frequency signal carries out relevant its pilot component of elimination low-pass filtered again；
If 2.2 reception signals are not in pilot time slot, i.e., in data transmission slots, then data transmission slots are received and believed
Number export and to give interference cancellation unit, and skip to step 6；
Step 3：PIM parameter estimation units receive pretreatment pilot time slot reception signal and carry out PIM parameter Estimations, then
The PIM nonlinear parameters for estimating to obtain are exported and give PIM parameter set units；PIM parameter set units are non-by the PIM of reception
Linear dimensions sets PIM model parameters；
Wherein, PIM model parameters refer to each term coefficient of PIM nonlinear models；
Step 4：The PIM model parameters that PIM reconstruction units are set using step 3 rebuild PIM interference signals；
Wherein, it is specially formula (3) to rebuild PIM interference signals：
Wherein,The order of this formula (3) power series model is represented,For the estimation of each term coefficient of PIM nonlinear models
Value,To rebuild PIM interference signals, sD(t) it is downstream signal, including descending pilot frequency time slot signal and downlink data transmission
Time slot signal；
Step 5：Double time delay estimation units receive pilot time slot reception signal and rebuild PIM interference signals, and carry out double
Time delay estimation is handled, and double time delays are estimated into obtained dual carrier time delay and PIM time delays export and give PIM parameter set units；PIM
Parameter set unit receives dual carrier time delay and PIM time delays, and adjustment PIM model parameters are set；PIM reconstruction units pass through adjustment
PIM model parameters rebuild PIM interference signals；
Wherein, double time delay estimations processing described in step 5, is comprised the following steps：
Step 5.1 pair time delay estimation module initializes pilot time slot reception signal and rebuilds the sequence of PIM interference signals
Moment；
Step 5.2 pair time delay estimation module rebuilds amendment PIM and rebuilds interference signal and actual reception PIM interference signals；
Specially：Amendment PIM, which is received, from PIM reconstruction units rebuilds interference signal；Received from data pre-processing unit from pre-
Manage data slot reception signal, i.e., it is actual to receive PIM interference signals；
Step 5.3 pair time delay estimation module carries out the computing based on correlation；
Specially：By rebuilding PIM interference signals S'pimWith the PIM signals S actually receivedpimBetween correlation, take two
The quadratic sum R of person's correlation2, R2The coordinate of peak value characterizes dual carrier time delay value；
R corresponding to different dual carrier time delay values2Value forms two-dimensional matrix, matrix peak pointCorresponding transverse and longitudinal coordinate point
Time delay and reconstruction PIM interference signals S' not between dual carrier signalpimWith the PIM interference signals S actually receivedpimBetween
Delay, τ2；
Wherein, double delay time signals refer to two delay time signals present in cancellation system, including dual carrier signal is relative
Delay, τ1And rebuild PIM interference signals S'pimWith the PIM interference signals S actually receivedpimBetween delay, τ2；
Step 5.4 pair time delay estimation module is searched for and records dual carrier relative time delay；
Specially：After reconstruction PIM interference signals carry out related calculation with actual reception PIM interference signals, PIM time delay domains are retrieved
On peak value, record peak amplitude and dual carrier relative time delay be worth；
Wherein, dual carrier relative time delay value refers to the time delay between dual carrier signal；
Step 5.5 pair time delay estimation module is searched for and records PIM relative time delays；
Specially：After obtaining dual carrier relative time delay, PIM interference signals S " is rebuildpim, with the PIM signals actually received
SpimCarry out related calculation and retrieve peak value, record peak amplitude is worth with PIM relative time delays；
Wherein, PIM relative time delays refer to rebuild PIM interference signals and the actual time delay received between PIM interference signals；
The double time delay estimation parameters of step 5.6 pair time delay estimation module output；
Specially：The double time delays tried to achieve are estimated into parameter, exports and gives PIM parameter set units, revised PIM parameters are
For the amendment PIM parameters without time delay；
Wherein, double time delay estimation parameters refer to dual carrier relative time delay and PIM relative time delays；
So far, from step 5.1 to step 5.6, double time delay estimations processing of step 5 is completed；
Step 6：Data pre-processing unit processing data transmission time slot reception signal, obtains preprocessed data transmission time slot
Reception signal, give the signal output to interference cancellation unit；PIM reconstruction units are exported PIM interference signals are rebuild to interference pair
Disappear unit；Offset the PIM model parameters that setting unit receives the output of PIM parameter estimation units, using constrained minimum output energy as
Criterion, sef-adapting filter parameter is set；
Wherein, sef-adapting filter parameter refers to filter tap weights；
Step 7：Interference cancellation unit receives preprocessed data transmission time slot reception signal and rebuilds PIM interference signals
Interference cancellation is carried out, the preprocessed data transmission time slot reception signal through interference cancellation is exported, skips to step 8；
Wherein, interference cancellation using adaptive filter algorithm to the preprocessed data transmission time slot reception signal of reception and
PIM interference signals are rebuild to be handled；Sef-adapting filter can automatic adjusument model parameter, realization quickly offset, when oneself
The adaptive filter algorithm convergence that adaptive filter uses, when filter result meets mean square error minimum, adaptive filter algorithm
Terminate；
Wherein, adaptive filter algorithm can be least mean square algorithm, and abbreviation LMS is horizontal using the cascade of M-1 delay cell
Realized to wave filter, M represents the length of transversal filter, by constantly adjusting the coefficient mean square error of transversal filter most
It is small；PIM interference signals after adaptive filter algorithm is handled are expressed asPreprocessed data through interference cancellation passes
Defeated time slot reception signal can represent equation below (4)：
Wherein, sR' (t) represents revised uplink signal；
Step 8：Whether interference cancellation unit terminates to determine to complete PIM interference cancellations, jumps according to this data transmission slots
To step 1；Or continue interference cancellation, step 6 is skipped to, is specially：
If 8.1 this data transmission slots terminate, PIM interference cancellations are completed, waits next pilot time slot to arrive, skips to
Step 1；
If 8.2 this data transmission slots do not terminate, interference cancellation unit transmits the preprocessed data through interference cancellation
Time slot reception signal exports；Subsequent time skips to step 6；
So far, from step 1 to step 8, a kind of passive intermodulation interference cancellation method based on the estimation of double time delays is completed.
Beneficial effect
A kind of passive intermodulation interference cancellation system and method based on the estimation of double time delays proposed by the present invention, takes into full account double
In carrier duplex system as caused by time delay time-varying PIM interference problems, with other passive intermodulation signal interference cancellation systems and side
Method is compared, and is had the advantages that：
1. the present invention, which on the basis of the requirement of low channel circumstance, realizes, changes sensitive, high-precision dual carrier PIM interference
Suppress in real time；
2. this method can accurately offset the interference of dual carrier passive intermodulation, Signal to Interference plus Noise Ratio gain is improved；
3. this method stable performance, is easy to hardware realization by Digital Implementation；
4. this method can be adjusted adaptively to the time-varying characteristics of dual carrier PIM signals, versatile；
5. proposing the method for double time delay estimations first, and realize dual carrier PIM AF panels.
Brief description of the drawings
Fig. 1 is the present invention " a kind of passive intermodulation interference cancellation system and method based on the estimation of double time delays " and embodiment 1
In system composition schematic diagram；
Fig. 2 is the present invention " a kind of passive intermodulation interference cancellation system and method based on the estimation of double time delays " and embodiment 1
In flow chart；
Fig. 3 is the present invention " a kind of passive intermodulation interference cancellation system and method based on the estimation of double time delays " and embodiment 2
The middle algorithm schematic diagram using double time delay estimation processing；
Fig. 4 is the present invention " a kind of passive intermodulation interference cancellation system and method based on the estimation of double time delays " and embodiment 2
The middle two-dimensional search schematic diagram using double time delay estimation processing；
Fig. 5 is the present invention " a kind of passive intermodulation interference cancellation system and method based on the estimation of double time delays " and embodiment 3
In have an estimation processing of unparalleled time delay offset effect contrast figure；
Fig. 6 is the present invention " a kind of passive intermodulation interference cancellation system and method based on the estimation of double time delays " and embodiment 3
In PIM interference signals are carried out under the conditions of received signal power and PIM interfering signal powers ratio (signal interference ratio) are 0dB~20dB
During suppression, the present invention carries out passive intermodulation interference cancellation and obtains the simulation curve comparison diagram that the bit error rate changes with signal interference ratio；
In Fig. 6, abscissa is signal interference ratio, and ordinate is the bit error rate.
Embodiment
In order to which the objects and advantages of the inventive method are better described, with reference to the accompanying drawing in embodiment, to the present invention
Technical scheme in embodiment carries out clear, complete description, it is clear that described embodiment is only that a present invention part is real
Example is applied, is only intended to help the method and its core concept for understanding the present invention.Meanwhile for those of ordinary skill in the art,
According to the thought of the present invention, there will be changes in specific embodiments and applications, in summary, in this specification
Appearance should not be construed as limiting the invention, and should belong to protection scope of the present invention.
With reference to embodiment to the passive intermodulation interference cancellation system proposed by the present invention based on the estimation of double time delays and side
Method is carried out deeper into careful elaboration and explanation.
Embodiment 1
The present embodiment specifically describe by the present invention " it is a kind of based on double time delays estimation passive intermodulation interference cancellation system and
System composition, function realization and the flow signal of method " application in a communications system.
Fig. 1 is the system of " a kind of passive intermodulation interference cancellation system and method based on the estimation of double time delays " in the present embodiment
Composition schematic diagram.As can be seen from Figure 1：The present embodiment just completes PIM AF panels, system only by way of Digital Implementation
Strong adaptability, it is easy to hardware realization.
The system receives double time slot signals by receiving pretreatment module, carries out Signal Pretreatment, during by pre-processing pilot tone
Gap signal output rebuilds module, double time delay estimation modules to PIM, by preprocessed data transmission time slot signal output to interference cancellation
Module, and carry out the estimation of PIM parameters；Module is rebuild by PIM and receives the PIM parameters of estimation, and carries out the reconstruction of PIM interference,
PIM interference output will be rebuild to double time delay estimation modules；Double time delay estimation modules receive PIM interference signals and rebuild PIM and do
Disturb signal and carry out double time delay estimations, the double delay parameters of estimation are fed back into PIM rebuilds module；PIM rebuilds module and receives estimation pair
Delay parameter, rebuild the amendment of PIM interference, amendment reconstruction PIM interference signals are exported and give interference cancellation module；Interference pair
The module that disappears sets and offsets wave filter, and rebuilding PIM interference signals by the amendment of reception carries out interference cancellation, and it is defeated to offset result
Go out.
The system function is：Double time slot signals are received by data pre-processing unit, double time slot reception signals carried out pre-
Processing, in pilot time slot, pretreatment pilot frequency time slot signal is exported single to estimating to PIM parameter estimation units and double time delays
Member, in data transmission slots, preprocessed data transmission time slot signal is transferred to interference cancellation unit；PIM parameter estimation units
Pretreatment pilot frequency time slot signal is received, and carries out PIM parameter Estimations, determines PIM every nonlinear parameter, and PIM will be estimated
Nonlinear parameter exports to PIM parameter set units and offsets setting unit；
PIM parameter set units set PIM to rebuild by the estimation PIM nonlinear parameters of reception or the double delay parameters of estimation
Model parameter；PIM reconstruction units rebuild PIM interference signals by the PIM reconstruction models of setting, in pilot time slot, will rebuild PIM
Interference signal is exported to double time delay estimation units, in data transmission slots, amendment is rebuild into PIM interference signals and exported to interference pair
Disappear unit；
Double time delay estimation units receive the preprocessed data transmission time slot signal and PIM weights of data pre-processing unit output
The reconstruction PIM interference signals of unit output are built, carry out double time delay estimations, and give the double time delay feedbacks for estimating to obtain to PIM parameters
Setting unit；
The PIM nonlinear parameters that setting unit receives the output of PIM parameter estimation units are offseted, with constrained minimum output energy
For criterion, sef-adapting filter parameter is set；Interference cancellation unit receives preprocessed data transmission time slot reception signal and again
Build PIM interference signals and carry out interference cancellation, the preprocessed data transmission time slot reception signal through interference cancellation is exported, after progress
Continuous signal transacting；
Fig. 2 is the algorithm of " a kind of passive intermodulation interference cancellation system and method based on the estimation of double time delays " in the present embodiment
Flow chart；
A kind of it can be seen that passive intermodulation interference cancellation based on the estimation of double time delays illustrated in the present embodiment
Method, comprise the following steps；
Step A：Reception signal；
Step B：Determine whether pilot time slot, and carry out corresponding operating, be specially：
If B.1 reception signal is in pilot time slot, i.e. Y in corresponding diagram 2, then pilot time slot reception signal is exported to number
According to processing unit, and skip to step C；
If B.2 reception signal is not in pilot time slot, i.e. the N in data transmission slots, namely corresponding diagram 2, then will
Data transmission slots reception signal is exported to data pre-processing unit, and skips to step G；
Step C：Reception signal pre-processes；
Specific to the present embodiment：The pilot time slot reception signal that data pre-processing unit processing receives, obtains pretreatment and leads
Frequency time slot reception signal, pretreatment pilot time slot reception signal is exported and gives PIM parameter estimation units；
Step D：PIM parameter Estimations；
Specific to the present embodiment：PIM parameter estimation units are received and the pretreatment of processing data pretreatment unit output is led
Frequency time slot reception signal, the estimation nonlinear parameter such as each term coefficient of PIM nonlinear models, and by PIM nonlinear parameters export to
PIM parameter set units；
Step E：PIM model parameters are set, PIM signal reconstructions；
Specific to the present embodiment：PIM parameter set units receive PIM nonlinear parameters, and non-linear by the PIM of reception
Parameter setting PIM model parameters；PIM reconstruction units rebuild PIM interference signals；
Wherein, PIM model parameters refer to each term coefficient of PIM nonlinear models；
Wherein, rebuilding PIM interference signals is specially：
Wherein,For the estimate of each term coefficient of PIM nonlinear models,To rebuild PIM interference signals, sD(t)
For downstream signal, including pilot time slot and data transmission slots；
Step F：Double time delay estimations, PIM rebuild amendment；
Specific to the present embodiment：Double time delay estimation units receive pilot time slot reception signal and rebuild PIM interference signals,
And double time delay estimation processing are carried out, the dual carrier time delay and PIM time delays that estimation is obtained export and give PIM parameter set units；
PIM parameter set units receive dual carrier time delay and PIM time delays, and adjustment PIM model parameters are set, to rebuilding PIM interference ginsengs
Number is modified；PIM reconstruction units rebuild PIM interference signals by the PIM model parameters of adjustment；
Step G：Reception signal pre-processes；
Specific to the present embodiment：Data pre-processing unit processing data transmission time slot reception signal, obtains preprocessed data
Transmission time slot reception signal, give the signal output to interference cancellation unit, be ready for interference cancellation；PIM reconstruction units will be repaiied
Reconstruction PIM interference signals after just, which export, gives interference cancellation unit；
Step H：Sef-adapting filter is set；
Specific to the present embodiment：The PIM model parameters that setting unit receives the output of PIM parameter estimation units are offseted, with about
Beam minimum output energy is criterion, sets sef-adapting filter parameter；
Wherein, sef-adapting filter parameter refers to filter tap weights.
Step I：PIM interference cancellations；
Specific to the present embodiment：Interference cancellation unit receives weight after preprocessed data transmission time slot reception signal and amendment
Build PIM interference signals and carry out interference cancellation, the preprocessed data transmission time slot reception signal through interference cancellation is exported, after progress
Continuous signal transacting；
Wherein, interference cancellation using adaptive filter algorithm to the preprocessed data transmission time slot reception signal of reception and
PIM interference signals are rebuild to be handled；Sef-adapting filter can automatic adjusument model parameter, realization quickly offset；
Wherein, adaptive filter algorithm uses least mean square algorithm (LMS) in the present embodiment, single using M-1 delay
The cascade transversal filter of member realizes that M represents the length of transversal filter, by the coefficient for constantly adjusting transversal filter
Mean square error is minimum；
Step J：Mean square error is minimum；
Specific to the present embodiment：When least mean square algorithm (LMS) wave filter convergence that interference cancellation unit uses, filtering knot
When fruit meets mean square error minimum, adaptive filter algorithm terminates；
Wherein, the PIM interference signals after adaptive filter algorithm is handled are expressed asThrough interference cancellation
Preprocessed data transmission time slot reception signal can represent as follows：
Wherein, sR' (t) represents revised uplink signal；
Step K：Signal output；
Specially：Whether interference cancellation unit terminates to determine to complete PIM interference cancellations, jumps according to this data transmission slots
To step A；Still continue interference cancellation, skip to step G, be specially：
If K.1 this data transmission slots terminates, PIM interference cancellations are completed, waits next pilot time slot to arrive, skips to
Step A；
If K.2 this data transmission slots does not terminate, interference cancellation unit transmits the preprocessed data through interference cancellation
Time slot reception signal exports；Subsequent time skips to step G；
So far, from step A to step K, a kind of passive intermodulation interference cancellation method based on the estimation of double time delays is completed.
Embodiment 2
The present embodiment is specifically described under dual carrier QPSK modulation, at the double time delay estimations described in step 5 of the present invention
Double time delay estimations processing that step F is used in reason and embodiment 1, its flow are as shown in Figure 3.From figure 3, it can be seen that double time delays
Estimation processing concretely comprises the following steps：
Step F.1 initialization sequence moment；
Specially：Progress Initialize installation, search delay, τ '1in=-τ1max, τ '1ed=τ1max, searching times i=in circulation
0, maximum search number L, search time delay median τ1mid=0, time delay retrieval step value Δ τ1=τ1max/2；
F.2, step prepares to rebuild PIM interference signals and actual reception PIM interference signals；
Specially：Receive preprocessed data time slot reception signal from data pre-processing unit, i.e., it is actual to receive PIM interference letters
Number；Amendment PIM, which is received, from PIM reconstruction units rebuilds interference signal；
F.3, step carries out related operation；
Specially：By rebuilding PIM interference signals S'pimWith the PIM signals S actually receivedpimBetween correlation, take two
The quadratic sum R of the road correlations of Zhe tetra-2, R2The coordinate of peak value characterizes time delay value.
R2=rII 2+rQI 2+rIQ 2+rQQ 2
Wherein：
Wherein, I (m) and Q (m) is the baseband signal of reception signal；WithFor PIM signal estimatesBase band
Signal.
R corresponding to different dual carrier time delay values2Value forms two-dimensional matrix, matrix peak pointCorresponding transverse and longitudinal coordinate point
Time delay and reconstruction PIM interference signals S' not between dual carrier signalpimWith the PIM interference signals S actually receivedpimBetween
Delay, τ2；
Wherein, double delay time signals refer to two delay time signals present in system, include the relative time delay of dual carrier signal
τ1And rebuild PIM interference signals S'pimWith the PIM interference signals S actually receivedpimBetween delay, τ2；
F.4, step searches for dual carrier relative time delay；
Specially：After reconstruction PIM interference signals carry out related calculation with actual reception PIM interference signals, PIM time delay domains are retrieved
On peak value, record peak amplitude and dual carrier relative time delay value τ1；
Wherein, dual carrier relative time delay value refers to the time delay between dual carrier signal；
F.5, step searches for PIM relative time delays；
Specially：After obtaining dual carrier relative time delay, PIM interference signals S " is rebuildpim, with the PIM signals actually received
SpimCarry out related calculation and retrieve peak value, record peak amplitude and PIM relative time delay values τ2；
Wherein, according to dual carrier time delay value τ1Caused two-way rebuilds PIM interference signals, is done respectively with the actual PIM that receives
Disturb signal SpimCarry out related calculation, obtain effective relevant peaks R 'in、R′ed, compare R 'in、R′edValue, if R 'in＞ R 'ed, order
τ1mid=τ '1in；Otherwise τ is made1mid=τ '1ed.Meanwhile make
Wherein, when reaching maximum retrieval number, obtained τ will be searched for for the last time1midObtained as final estimation
Dual carrier time delay；Otherwise, τ ' is made1in=τ1mid-Δτ1, τ '1ed=τ1mid+Δτ1, walk in return, continue to search for；
Wherein, PIM relative time delays refer to rebuild PIM interference signals and the actual time delay received between PIM interference signals；
F.6, step exports double time delay estimation parameters；
Specially：The double time delays tried to achieve are estimated into parameter, exports and gives PIM parameter set units, revised PIM parameters are
For the amendment PIM parameters without time delay；
Wherein, double time delay estimation parameters refer to dual carrier relative time delay and PIM relative time delays；
So far, from step F.1 to step F.6, complete step F in embodiment 1 double time delay estimations processing；
Fig. 3 is that a kind of " passive intermodulation interference cancellation system and method based on the estimation of double time delays " use is double in the present embodiment
The schematic diagram of time delay estimation processing.
It can be seen that the double time delays estimation handling process illustrated in the present embodiment, main to include related, search
The step such as peak value and delay compensation；
Wherein, it is related to refer to, using PIM interference signals and the actual correlation received between PIM interference signals is rebuild, do
Related operation, seek the quadratic sum of both correlations；Search peak refers in dual carrier time delay and actual reception PIM interference signals
Prolong and scanned on the two-dimensional field, find the peak value on the two-dimensional field；Delay compensation refers to after completing double time delay estimations, when obtaining double
Prolong estimation parameter, delay compensation amendment is carried out to PIM reconstruction models；Fig. 4 is correlation R under two-dimentional time delay2Schematic three dimensional views.
Embodiment 3
The present embodiment is handled according to double time delay estimations described in the system flow described in embodiment 1 and embodiment 2, is specifically explained
The passive intermodulation interference cancellation result that dual carrier qpsk modulation signal is performed step 1 of the present invention and carried out to step 8 has been stated,
Comparative result is as shown in Figure 5, Figure 6.
In Fig. 5 (a), transverse axis represents the time, and the longitudinal axis represents signal amplitude；Curve is handled for unparalleled time delay estimation in Fig. 5 (a)
Offset front and rear Contrast on effect, wherein darker curve represents interference signal, and lighter curve represents LMS and offsets rear signal.Fig. 5
(b) in, transverse axis represents the time, and the longitudinal axis represents signal amplitude；Curve is to have offseting for double time delay estimation processing front and rear in Fig. 5 (b)
Contrast on effect, wherein darker curve represents interference signal, and lighter curve represents LMS and offsets rear signal.It can be seen by contrast
Go out, when not carrying out double time delay estimations, still remaining very big interference signal after interference cancellation；Estimate in the double time delays of progress and carry out time delay
Interference cancellation after compensation, the interference signal of only remaining very little, it can be seen that, when double time delay estimations processing can effectively improve pair
Become PIM signals offsets effect.
In Fig. 6, transverse axis represents signal interference ratio, unit dB；The longitudinal axis represents the bit error rate, unit bit；Red curve in Fig. 6
For by the ber curve of passive intermodulation interference effect；Blue curve line is to be arrived through the method and step one that offsets proposed by the invention
The ber curve of passive intermodulation AF panel obtained by step 9.
As can be seen from Fig. 6, it is very poor in communication environment, signal interference ratio (SIR) from 0dB~20dB change when, through the present invention carried
Go out the passive intermodulation AF panel bit error rate offseted obtained by method and be substantially better than the bit error rate disturbed by passive intermodulation；It can be seen that this reality
Apply example and use double time delay estimation processing described in system flow described in embodiment 1 and embodiment 2, can be in higher signal interference ratio
Under the conditions of complete Adaptive Suppression to time-varying PIM interference, increase substantially anti-PIM interference performances, reduce the bit error rate.
Although by referring to some of the preferred embodiment of the invention, the present invention is shown and described,
It will be understood by those skilled in the art that can to it, various changes can be made in the form and details, without departing from this hair
Bright spirit and scope.
Claims (8)
- A kind of 1. passive intermodulation interference cancellation system and method based on the estimation of double time delays, it is characterised in that：It is based on including one kind The passive intermodulation interference cancellation system of double time delay estimations, abbreviation cancellation system；With a kind of passive intermodulation based on the estimation of double time delays Interference cancellation method, referred to as offsets method；Wherein, cancellation system is the signal processing of the communication system of antenna transmit-receive sharing；The communication system of antenna transmit-receive sharing System includes duplexer, isolator, coaxial cable, connector, antenna, the passive device based on load, causes passive intermodulation to do Disturb；Cancellation system mainly includes receiving pretreatment module, PIM reconstructions module, double time delay estimation modules and interference cancellation mould Block；Wherein, receiving pretreatment module includes PIM parameter estimation units and data pre-processing unit；PIM, which rebuilds module, includes PIM Parameter set unit and PIM reconstruction units；Double time delay estimation modules include double time delay estimation units；Interference cancellation module include pair Disappear setting unit and interference cancellation unit；The annexation of each module of cancellation system is：Pretreatment module is received with PIM reconstructions module, double time delay estimation modules and interference cancellation module to be connected；PIM rebuilds mould Block is connected with receiving pretreatment module, double time delay estimation modules and interference cancellation module；Double time delay estimation modules are pre- with receiving Processing module and PIM rebuild module and are connected；Interference cancellation module is rebuild module and is connected with receiving pretreatment module and PIM；The annexation of cancellation system each unit is：PIM parameter estimation units and data pre-processing unit, PIM parameter set units and offset setting unit and be connected；Data Pretreatment unit is connected with PIM parameter estimation units, double time delay estimation units and interference cancellation unit；PIM parameter setting lists Member is connected with PIM parameter estimation units, double time delay estimation units and PIM reconstruction units；PIM reconstruction units are set with PIM parameters Unit, double time delay estimation units and interference cancellation unit is put to be connected；Double time delay estimation units and data pre-processing unit, PIM Parameter set unit and PIM reconstruction units are connected；Offset setting unit and PIM parameter estimation units and interference cancellation unit It is connected；Interference cancellation unit and data pre-processing unit, PIM reconstruction units and offset setting unit and be connected；Each functions of modules of cancellation system is as follows：The function of receiving pretreatment module is used in pilot time slot and data transmission slots reception signal, and it is non-thread to carry out PIM Property Parameter analysis and Signal Pretreatment, output pretreatment pilot time slot reception signal and pretreatment non-pilot time slot reception signal； Wherein, pretreatment non-pilot time slot reception signal is also known as preprocessed data time slot reception signal；Will pretreatment pilot time slot letter Number export and to rebuild module, time delay estimation module and interference cancellation module to PIM；It is defeated that PIM rebuilds module reception pretreatment module The PIM nonlinear parameters gone out, PIM interference signal reconstructions are carried out using the PIM nonlinear parameters, and by rebuilding, PIM interference signals are defeated Go out to double time delay estimation modules and interference cancellation module；Double time delay estimation modules, which receive, rebuilds PIM interference signals and pretreatment Pilot time slot reception signal carries out double time delay estimations, and the double delay parameters for estimating to obtain are fed back into PIM rebuilds module, amendment weight Build PIM interference signals；Interference cancellation unit receives amendment and rebuilds PIM interference signals and the progress of preprocessed data time slot reception signal Interference cancellation；Cancellation system each unit function is as follows：The pilot time slot reception signal and data transmission slots reception signal that data pre-processing unit processing receives, pretreatment is led Frequency time slot reception signal is exported to PIM parameter set units and double time delay estimation units, and preprocessed data transmission time slot is connect Receive signal output and give interference cancellation unit；PIM parameter estimation units receive pretreatment pilot time slot reception signal, and estimation is obtained PIM nonlinear parameters export and give PIM parameter set units；For PIM parameter set units in pilot time slot, the PIM nonlinear parameters for passing through reception set PIM model parameters；Passed in data Defeated time slot, receives dual carrier time delay and PIM time delays, and adjustment PIM model parameters are set；PIM reconstruction units are in pilot time slot, root Double time delay estimation units are given according to the PIM Model Reconstruction PIM interference signals of arrange parameter, and by the signal output；In data transfer Time slot, amendment PIM interference signals are rebuild by the PIM model parameters of adjustment, and give the signal output to interference cancellation unit；Double time delay estimation units receive pilot time slot reception signal and rebuild PIM interference signals, and carry out at double time delay estimations Reason, the dual carrier time delay and PIM time delays that estimation is obtained export and give PIM parameter set units；The PIM model parameters that setting unit receives the output of PIM parameter estimation units are offseted, are defined by constrained minimum output energy Then, sef-adapting filter parameter is set；Interference cancellation unit receives preprocessed data transmission time slot reception signal and rebuilds PIM Interference signal carries out interference cancellation, and the preprocessed data transmission time slot reception signal through interference cancellation is exported, subsequently believed Number processing；The present invention is carried out using the method that offsets based on the estimation of double time delays to the double time slot reception signals disturbed containing dual carrier PIM AF panel, double time slot reception signals include pilot time slot reception signal and data transmission slots reception signal.
- 2. a kind of passive intermodulation interference cancellation system and method based on the estimation of double time delays according to claim 1, it is special Sign is：Method is offseted, is comprised the following steps that：Step 1：In the communication system of antenna transmit-receive sharing, duplexer transmitting dual carrier QPSK modulation downstream signals, then receive Uplink signal；Step 2：The uplink signal that data pre-processing unit processing step one receives, judges whether reception signal is in Pilot time slot, determined to skip to step 3 or step 6 according to judged result；Step 3：PIM parameter estimation units receive pretreatment pilot time slot reception signal and carry out PIM parameter Estimations, then will estimate The PIM nonlinear parameters that meter obtains, which export, gives PIM parameter set units；PIM parameter set units are non-linear by the PIM of reception Parameter setting PIM model parameters；Wherein, PIM model parameters refer to each term coefficient of PIM nonlinear models；Step 4：The PIM model parameters that PIM reconstruction units are set using step 3 rebuild PIM interference signals；Step 5：Double time delay estimation units receive pilot time slot reception signal and rebuild PIM interference signals, and carry out double time delays Estimation is handled, and double time delays are estimated into obtained dual carrier time delay and PIM time delays export and give PIM parameter set units；PIM parameters Setting unit receives dual carrier time delay and PIM time delays, and adjustment PIM model parameters are set；PIM reconstruction units pass through adjustment PIM model parameters rebuild PIM interference signals；Step 6：Data pre-processing unit processing data transmission time slot reception signal, obtain the reception of preprocessed data transmission time slot Signal, give the signal output to interference cancellation unit；Reconstruction PIM interference signals are exported and give interference cancellation list by PIM reconstruction units Member；The PIM model parameters that setting unit receives the output of PIM parameter estimation units are offseted, using constrained minimum output energy as criterion, Sef-adapting filter parameter is set；Wherein, sef-adapting filter parameter refers to filter tap weights；Step 7：Interference cancellation unit receives preprocessed data transmission time slot reception signal and rebuilds PIM interference signals and carries out Interference cancellation, the preprocessed data transmission time slot reception signal through interference cancellation is exported, jumps to step 8；Step 8：Whether interference cancellation unit terminates to determine completion PIM interference cancellations according to this data transmission slots, skips to step Rapid one；Or continue interference cancellation, skip to step 6；So far, from step 1 to step 8, a kind of passive intermodulation interference cancellation method based on the estimation of double time delays is completed.
- 3. a kind of passive intermodulation interference cancellation system and method based on the estimation of double time delays according to claim 2, it is special Sign is：In step 1, downstream signal includes descending pilot frequency time slot signal and descending non-pilot time slot signal, and downstream signal produces PIM interference signals sPIM(t) formula (1) can be expressed as：<mrow> <msub> <mi>s</mi> <mrow> <mi>P</mi> <mi>I</mi> <mi>M</mi> </mrow> </msub> <mrow> <mo>(</mo> <mi>t</mi> <mo>)</mo> </mrow> <mo>=</mo> <munderover> <mo>&Sigma;</mo> <mrow> <mi>l</mi> <mo>=</mo> <mn>1</mn> </mrow> <mi>&infin;</mi> </munderover> <msub> <mi>a</mi> <mi>l</mi> </msub> <msub> <mi>s</mi> <mi>D</mi> </msub> <msup> <mrow> <mo>(</mo> <mi>t</mi> <mo>)</mo> </mrow> <mi>l</mi> </msup> <mo>-</mo> <mo>-</mo> <mo>-</mo> <mrow> <mo>(</mo> <mn>1</mn> <mo>)</mo> </mrow> </mrow>Wherein, sD(t) it is downstream signal,Represent to each single item alsD(t)lSummed, αlRepresent po wer series modules Type order l range value, i.e.,：PIM interference signals caused by downstream signal using power series model represent, wherein, downstream signal In pilot frequency time slot signal, referred to as descending pilot frequency time slot signal is linear FM signal, also known as LFM signals；Wherein, it is descending Non-pilot time slot signal is also referred to as downlink data time slot signal；The uplink signal of reception includes upward signal, PIM interference signals and noise three parts, can use equation below (2) To represent：sR(t)=sUP(t)+IPIM(t)*h(t)+n0(t) (2)Wherein, sR(t) it is the uplink signal received, sUP(t) it is upward signal, n0(t) it is noise, IPIM(t) it is descending letter PIM interference signals caused by number, including PIM interference signals s caused by pilot time slot and data transmission slotsPIM(t), h (t) tables Show that PIM interference signals are transmitted into the coupling channel impulse response of reception, I by duplexerPIM(t) * h (t) represent that duplexer receives PIM interference signals, * represent convolution algorithm.
- 4. a kind of passive intermodulation interference cancellation system and method based on the estimation of double time delays according to claim 2, it is special Sign is：Step 2: it is specially：If 2.1 reception signals are in pilot time slot, the pilot component in pilot time slot reception signal is removed, pretreatment is obtained and leads Frequency time slot reception signal, i.e. PIM interference signals, and this signal output is estimated into list to PIM parameter estimation units and double time delays Member, and skip to step 3；Wherein, the pilot component in pilot time slot reception signal is removed, is believed especially by by pilot time slot reception signal and pilot tone Number carry out relevant its pilot component of elimination low-pass filtered again；It is if 2.2 reception signals are not in pilot time slot, i.e., in data transmission slots, then data transmission slots reception signal is defeated Go out and give interference cancellation unit, and skip to step 6.
- 5. a kind of passive intermodulation interference cancellation system and method based on the estimation of double time delays according to claim 2, it is special Sign is：In step 4, it is specially formula (3) to rebuild PIM interference signals：<mrow> <msub> <mover> <mi>I</mi> <mo>^</mo> </mover> <mrow> <mi>P</mi> <mi>I</mi> <mi>M</mi> </mrow> </msub> <mrow> <mo>(</mo> <mi>t</mi> <mo>)</mo> </mrow> <mo>=</mo> <msub> <mo>&Sigma;</mo> <mover> <mi>l</mi> <mo>^</mo> </mover> </msub> <msub> <mi>a</mi> <mover> <mi>l</mi> <mo>^</mo> </mover> </msub> <msub> <mi>s</mi> <mi>D</mi> </msub> <msup> <mrow> <mo>(</mo> <mi>t</mi> <mo>)</mo> </mrow> <mover> <mi>l</mi> <mo>^</mo> </mover> </msup> <mo>-</mo> <mo>-</mo> <mo>-</mo> <mrow> <mo>(</mo> <mn>3</mn> <mo>)</mo> </mrow> </mrow>Wherein,The order of this formula (3) power series model is represented,For the estimate of each term coefficient of PIM nonlinear models,To rebuild PIM interference signals, sD(t) it is downstream signal, including when descending pilot frequency time slot signal and downlink data transmission Gap signal.
- 6. a kind of passive intermodulation interference cancellation system and method based on the estimation of double time delays according to claim 2, it is special Sign is：Double time delay estimations processing described in step 5, is comprised the following steps：Step 5.1 initializes pilot time slot reception signal and rebuild the sequence moment of PIM interference signals；Step 5.2 receives preprocessed data time slot reception signal from data pre-processing unit, i.e., actual to receive PIM interference signals； Amendment PIM, which is received, from PIM reconstruction units rebuilds interference signal；Step 5.3 pair time delay estimation module is rebuild interference signal to actual reception PIM interference signals and amendment PIM and is related as Main computing；Specially：By rebuilding PIM interference signals S'pimWith the PIM signals S actually receivedpimBetween correlation, take the two phase The quadratic sum R of pass value2, R2The coordinate of peak value characterizes dual carrier time delay value；R corresponding to different dual carrier time delay values2Value forms two-dimensional matrix, matrix peak pointCorresponding transverse and longitudinal coordinate difference Time delay and reconstruction PIM interference signals S' between dual carrier signalpimWith the PIM interference signals S actually receivedpimBetween Delay, τ2；Wherein, double delay time signals refer to two delay time signals present in cancellation system, include the relative time delay τ of dual carrier signal1 And rebuild PIM interference signals S'pimWith the PIM interference signals S actually receivedpimBetween delay, τ2；Step 5.4 pair time delay estimation module is searched for and records dual carrier relative time delay；Specially：After reconstruction PIM interference signals carry out related calculation with actual reception PIM interference signals, retrieve in PIM time delay domains Peak value, record peak amplitude are worth with dual carrier relative time delay；Wherein, dual carrier relative time delay value refers to the time delay between dual carrier signal；Step 5.5 pair time delay estimation module is searched for and records PIM relative time delays；Specially：After obtaining dual carrier relative time delay, PIM interference signals S' is rebuildp'im, with the PIM signals S actually receivedpimDo Related operation simultaneously retrieves peak value, and record peak amplitude is worth with PIM relative time delays；Wherein, PIM relative time delays refer to rebuild PIM interference signals and the actual time delay received between PIM interference signals；The double time delay estimation parameters of step 5.6 pair time delay estimation module output；Specially：The double time delays tried to achieve are estimated parameter by double time delay estimation modules, are exported and are given PIM parameter set units, after amendment PIM parameters be the amendment PIM parameters without time delay；Wherein, double time delay estimation parameters refer to dual carrier relative time delay and PIM relative time delays；So far, from step 5.1 to step 5.6, double time delay estimation processing are completed.
- 7. a kind of passive intermodulation interference cancellation system and method based on the estimation of double time delays according to claim 2, it is special Sign is：Preprocessed data transmission time slot reception signal of the interference cancellation using adaptive filter algorithm to reception in step 7 And rebuild PIM interference signals and handled；Sef-adapting filter can automatic adjusument model parameter, realization quickly offset, When the adaptive filter algorithm convergence that sef-adapting filter uses, when filter result meets mean square error minimum, adaptive-filtering Algorithm terminates；Wherein, adaptive filter algorithm can be least mean square algorithm, referred to as LMS, using the cascade transverse direction of M-1 delay cell Wave filter realizes that M represents the length of transversal filter, by constantly adjusting the coefficient mean square error of transversal filter most It is small；PIM interference signals after adaptive filter algorithm is handled are expressed asPreprocessed data through interference cancellation Transmission time slot reception signal can represent equation below (4)：<mrow> <msup> <msub> <mi>s</mi> <mi>R</mi> </msub> <mo>&prime;</mo> </msup> <mrow> <mo>(</mo> <mi>t</mi> <mo>)</mo> </mrow> <mo>=</mo> <msub> <mi>s</mi> <mi>R</mi> </msub> <mrow> <mo>(</mo> <mi>t</mi> <mo>)</mo> </mrow> <mo>-</mo> <msup> <msub> <mover> <mi>I</mi> <mo>^</mo> </mover> <mrow> <mi>P</mi> <mi>I</mi> <mi>M</mi> </mrow> </msub> <mo>&prime;</mo> </msup> <mrow> <mo>(</mo> <mi>t</mi> <mo>)</mo> </mrow> <mo>-</mo> <mo>-</mo> <mo>-</mo> <mrow> <mo>(</mo> <mn>4</mn> <mo>)</mo> </mrow> </mrow>Wherein, sR' (t) represents revised uplink signal.
- 8. a kind of passive intermodulation interference cancellation system and method based on the estimation of double time delays according to claim 2, it is special Sign is：Step 8, it is specially：If 8.1 this data transmission slots terminate, PIM interference cancellations are completed, waits next pilot time slot to arrive, skips to step One；If 8.2 this data transmission slots do not terminate, interference cancellation unit is by the preprocessed data transmission time slot through interference cancellation Reception signal exports；Subsequent time skips to step 6.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710729053.0A CN107453782A (en) | 2017-08-23 | 2017-08-23 | A kind of passive intermodulation interference cancellation system and method based on the estimation of double time delays |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710729053.0A CN107453782A (en) | 2017-08-23 | 2017-08-23 | A kind of passive intermodulation interference cancellation system and method based on the estimation of double time delays |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN107453782A true CN107453782A (en) | 2017-12-08 |
Family
ID=60494093
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710729053.0A Pending CN107453782A (en) | 2017-08-23 | 2017-08-23 | A kind of passive intermodulation interference cancellation system and method based on the estimation of double time delays |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107453782A (en) |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110661546A (en) * | 2019-09-25 | 2020-01-07 | 北京科技大学 | Method and system for eliminating harmonic interference digital domain in 5G terminal based on NSA architecture |
| CN110808750A (en) * | 2019-11-08 | 2020-02-18 | 电子科技大学 | Method and device for suppressing adjacent channel interference based on inverse filtering |
| WO2020190185A1 (en) * | 2019-03-20 | 2020-09-24 | Telefonaktiebolaget Lm Ericsson (Publ) | Method and control device for mitigating interference |
| CN111917676A (en) * | 2020-08-11 | 2020-11-10 | 电子科技大学 | Linear frequency modulation interference cancellation method |
| WO2021046677A1 (en) * | 2019-09-09 | 2021-03-18 | 华为技术有限公司 | Pim self-cancellation method and device |
| WO2021080566A1 (en) * | 2019-10-22 | 2021-04-29 | Nokia Solutions And Networks Oy | Estimating delays |
| WO2021092816A1 (en) * | 2019-11-13 | 2021-05-20 | Oppo广东移动通信有限公司 | Method and apparatus for reconstructing intermodulation interference signal |
| CN112970232A (en) * | 2018-11-08 | 2021-06-15 | 华为技术有限公司 | Method, equipment and system for eliminating interference |
| WO2021184232A1 (en) * | 2020-03-18 | 2021-09-23 | Telefonaktiebolaget Lm Ericsson (Publ) | Removal of passive intermodulation in antenna systems |
| CN116633465A (en) * | 2023-07-24 | 2023-08-22 | 四川恒湾科技有限公司 | Real-time passive intermodulation detection method based on resource block as unit |
| CN117492049A (en) * | 2023-12-29 | 2024-02-02 | 中国人民解放军国防科技大学 | High-precision time service method and device under anti-interference condition |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106301417A (en) * | 2016-11-01 | 2017-01-04 | 北京理工大学 | A kind of passive intermodulation interference cancellation method based on sparse fraction rank Fourier transform |
-
2017
- 2017-08-23 CN CN201710729053.0A patent/CN107453782A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106301417A (en) * | 2016-11-01 | 2017-01-04 | 北京理工大学 | A kind of passive intermodulation interference cancellation method based on sparse fraction rank Fourier transform |
Non-Patent Citations (1)
| Title |
|---|
| 张序琦: "基于数字信号处理的无源互调干扰对消", 《CNKI》 * |
Cited By (21)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112970232A (en) * | 2018-11-08 | 2021-06-15 | 华为技术有限公司 | Method, equipment and system for eliminating interference |
| CN112970232B (en) * | 2018-11-08 | 2022-07-12 | 华为技术有限公司 | Method, equipment and system for eliminating interference |
| US11895522B2 (en) | 2018-11-08 | 2024-02-06 | Huawei Technologies Co., Ltd. | Interference cancellation method, device, and system |
| US11929773B2 (en) | 2019-03-20 | 2024-03-12 | Telefonaktiebolaget Lm Ericsson (Publ) | Method and control device for mitigating interference |
| WO2020190185A1 (en) * | 2019-03-20 | 2020-09-24 | Telefonaktiebolaget Lm Ericsson (Publ) | Method and control device for mitigating interference |
| WO2021046677A1 (en) * | 2019-09-09 | 2021-03-18 | 华为技术有限公司 | Pim self-cancellation method and device |
| CN110661546B (en) * | 2019-09-25 | 2020-08-25 | 北京科技大学 | Method and system for eliminating harmonic interference digital domain in 5G terminal based on NSA architecture |
| CN110661546A (en) * | 2019-09-25 | 2020-01-07 | 北京科技大学 | Method and system for eliminating harmonic interference digital domain in 5G terminal based on NSA architecture |
| WO2021080566A1 (en) * | 2019-10-22 | 2021-04-29 | Nokia Solutions And Networks Oy | Estimating delays |
| CN110808750A (en) * | 2019-11-08 | 2020-02-18 | 电子科技大学 | Method and device for suppressing adjacent channel interference based on inverse filtering |
| 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 |
| WO2021092816A1 (en) * | 2019-11-13 | 2021-05-20 | Oppo广东移动通信有限公司 | Method and apparatus for reconstructing intermodulation interference signal |
| CN114073012A (en) * | 2019-11-13 | 2022-02-18 | Oppo广东移动通信有限公司 | Reconstruction method and device of intermodulation interference signal |
| WO2021184232A1 (en) * | 2020-03-18 | 2021-09-23 | Telefonaktiebolaget Lm Ericsson (Publ) | Removal of passive intermodulation in antenna systems |
| US11996879B2 (en) | 2020-03-18 | 2024-05-28 | Telefonaktiebolaget Lm Ericsson (Publ) | Removal of passive intermodulation in antenna systems |
| CN111917676B (en) * | 2020-08-11 | 2021-07-27 | 电子科技大学 | Linear frequency modulation interference cancellation method |
| CN111917676A (en) * | 2020-08-11 | 2020-11-10 | 电子科技大学 | Linear frequency modulation interference cancellation method |
| CN116633465B (en) * | 2023-07-24 | 2023-10-13 | 四川恒湾科技有限公司 | Real-time passive intermodulation detection method based on resource block as unit |
| CN116633465A (en) * | 2023-07-24 | 2023-08-22 | 四川恒湾科技有限公司 | Real-time passive intermodulation detection method based on resource block as unit |
| CN117492049A (en) * | 2023-12-29 | 2024-02-02 | 中国人民解放军国防科技大学 | High-precision time service method and device under anti-interference condition |
| CN117492049B (en) * | 2023-12-29 | 2024-04-02 | 中国人民解放军国防科技大学 | High-precision time service method and device under anti-interference condition |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107453782A (en) | A kind of passive intermodulation interference cancellation system and method based on the estimation of double time delays | |
| CN103986482B (en) | A kind of passive intermodulation disturbance restraining method based on adaptive-filtering | |
| CN107135024A (en) | A kind of mixed-beam figuration Iterative Design method of low complex degree | |
| CN106301417B (en) | A kind of passive intermodulation interference cancellation method based on sparse fraction rank Fourier transform | |
| CN105049067B (en) | A kind of passive intermodulation interference cancellation method based on pilot signal | |
| CN107592134A (en) | A kind of multi-tap towards co-channel full duplex simultaneously simulates self-interference cancellation method | |
| CN105471530B (en) | A kind of method of the raising reception signal simulation accuracy based on baseband equivalence channel model | |
| EP2453587B1 (en) | Method, apparatus and system for transmitting channel state information | |
| CN106330219A (en) | Passive intermodulation interference cancellation method and system based on recursive network | |
| CN103401824A (en) | Frequency selectivity MIMO (multiple input multiple output) system space-time blind equalizer method based on MNM (modified Newton method) | |
| Bashkirov et al. | Method of advanced channel estimation in OFDM systems by regression technique | |
| Zhang et al. | Adaptive digital self-interference cancellation for millimeter-wave full-duplex backhaul systems | |
| CN113422745A (en) | Air-sea wireless channel estimation method based on deep learning | |
| CN104022984A (en) | Channel equalization method based on bidirectional noise prediction decision feedback | |
| CN104378787A (en) | Flat rapid fading long-distance channel predicting method based on extension Prony algorithm | |
| Cai et al. | Intelligent reflecting surface assisted multi-cell multi-band wireless networks | |
| US10601455B2 (en) | Mitigating passive intermodulation interference in a MIMO wireless network | |
| Zhou et al. | A Semiempirical MIMO channel model in obstructed viaduct scenarios on high‐speed railway | |
| CN107517086B (en) | A kind of damage compensation method and device | |
| CN106656879B (en) | A kind of high-speed and High-order variable-step self-adaptive equalization methods | |
| Ryabova et al. | Method of Experimental Estimating Processing Gain from Dispersion Correction in a Wideband Transionospheric Radio Channel | |
| CN115022129B (en) | Channel estimation method of multi-user uplink transmission RIS auxiliary system based on ANM | |
| Zhao et al. | Performance analysis of bit error rate of data link system under pulse LFM interference in time-varying rayleigh channel | |
| CN107196686A (en) | A kind of extensive mimo system signal detecting method with pretreatment operation | |
| Suryana | The Rainfall Intensity Effects on 1–13 GHz UWB‐Based 5G System for Outdoor Applications |
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 | ||
| WD01 | Invention patent application deemed withdrawn after publication | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20171208 |