CN106656877B

CN106656877B - Interference elimination method and device

Info

Publication number: CN106656877B
Application number: CN201510714087.3A
Authority: CN
Inventors: 刘庆伟; 储建栋; 苏威
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2015-10-28
Filing date: 2015-10-28
Publication date: 2019-12-17
Anticipated expiration: 2035-10-28
Also published as: CN106656877A

Abstract

The embodiment of the invention provides an interference elimination method and device, relates to the field of communication, and is used for reducing interference in a first communication system under a shared spectrum scene so as to improve the throughput rate of the first communication system, and is applied to a first cell which is provided with a second cell adjacent to the first cell, wherein the first cell belongs to the first communication system, the second cell belongs to a second communication system, and shared spectrum exists between the first cell and the second cell, and the method comprises the following steps: the base station of the first cell performs interference pre-elimination on the received uplink signal according to a preset strategy to obtain an interference pre-elimination signal; wherein, the uplink signal includes a first uplink signal sent by the user equipment in the first cell and a second uplink signal sent by the user equipment in the second cell; and eliminating the interference signals in the interference pre-elimination signals according to the channel response estimation value of the interference pre-elimination signals. The embodiment of the invention is applied to different systems with shared frequency spectrum.

Description

interference elimination method and device

Technical Field

The embodiment of the invention relates to the field of communication, in particular to an interference elimination method and device.

Background

With the rapid development of the mobile industry, the deployment of LTE (Long Term Evolution) system has become global. The 1800MHz spectrum has become the first choice for LTE system deployment due to its excellent coverage capability. However, 1800MHz spectrum resources are scarce, and most of the spectrum resources are currently used for GSM (Global System for Mobile Communication) System deployment. Since the GSM system still has a considerable number of hotspots in many areas at present, operators cannot directly reschedule the 1800MHz spectrum of all GSM systems into the 1800MHz spectrum of the LTE system for full-network deployment. In addition, the 1800M bandwidth of 50% operators is 10M-25M, which cannot meet the large bandwidth requirements of the GSM system and the LTE system at the same time, so that the spectrum resources of the GSM system and the LTE system are not limited by fixed configuration any more, but the spectrum resources are distributed according to the needs, the LTE system can share the shared spectrum when the traffic of the GSM system is idle, and the GSM can share the shared spectrum when the traffic of the GSM is busy; namely, dynamic sharing of the spectrum of the GSM system and the LTE system. The dynamic sharing of spectrum for GSM and LTE systems is shown in fig. 1.

Because the GSM system and the LTE system are co-established on the 1800MHz frequency spectrum and belong to the same-frequency networking, carrier energy of the GSM system in the shared frequency spectrum may leak into the frequency spectrum of the LTE system, which may generate strong interference to the sideband frequency spectrum of the LTE system, resulting in degradation of demodulation performance of the LTE system and increase of error rate, so the LTE system needs to suppress or eliminate the interference generated by the GSM system urgently.

in the prior art, a common Interference suppression or elimination method is an Interference suppression Combining (IRC) technology, for example, the main method for inter-cell suppression or elimination in an LTE system is the IRC technology, as shown in fig. 2, the IRC technology is a diversity Combining technology that calculates a covariance matrix of an Interference signal and a white noise through a received signal or a received signal after pilot frequency is performed, and performs Interference suppression Combining on the received signal by using the covariance matrix of the Interference signal and the white noise, thereby suppressing the Interference signal.

because the GSM system is a narrowband signal, the signal power of the GSM system is stronger than that of the LTE system under the same level condition, and the strength of the interference signal power has a greater influence on the accuracy of the interference covariance matrix, when the interference generated by the GSM system is suppressed or eliminated by using the IRC technology in the situation that the GSM system and the LTE system share a spectrum, the interference signal cannot be effectively eliminated or suppressed, which may cause the increase of the error rate and the decrease of the throughput rate of the eNodeB (evolved nodeb) in the LTE system.

disclosure of Invention

embodiments of the present invention provide an interference cancellation method and apparatus, so as to reduce interference in a first communication system in a spectrum sharing scenario, thereby improving throughput of the first communication system.

In order to achieve the above purpose, the embodiment of the invention adopts the following technical scheme:

In a first aspect, an embodiment of the present invention provides an interference cancellation method, where the method is applied to a first cell, where the first cell has a second cell in a neighboring cell, where the first cell belongs to a first communication system, the second cell belongs to a second communication system, and there is a shared spectrum between the first cell and the second cell, and the method includes:

the base station of the first cell performs interference pre-elimination on the received uplink signal according to a preset strategy to obtain an interference pre-elimination signal; wherein the uplink signal includes a first uplink signal sent by the user equipment in the first cell and a second uplink signal sent by the user equipment in the second cell;

and carrying out interference elimination on the interference pre-elimination signal according to the channel response estimation value of the interference pre-elimination signal.

With reference to the first aspect, in a first possible implementation manner of the first aspect, before the performing, by the base station of the first cell, interference pre-cancellation on the received uplink signal according to a preset policy to obtain an interference pre-cancelled signal, the method further includes:

Acquiring an energy value of the second uplink signal;

and if the energy value of the second uplink signal is greater than a first threshold, the base station of the first cell performs interference pre-elimination on the received uplink signal according to a preset strategy.

with reference to the first possible implementation manner of the first aspect, in a second possible implementation manner of the first aspect, the acquiring an energy value of the second uplink signal includes:

acquiring a frequency point of the second cell;

and calculating energy values of M subcarriers including the frequency point of the second cell to obtain the energy value of the second uplink signal, wherein M is more than or equal to 12 and less than or equal to 60.

With reference to the second possible implementation manner of the first aspect, in a third possible implementation manner of the first aspect, the M subcarriers include 12 subcarriers selected by taking a frequency point of the second communication system as a center.

With reference to the second possible implementation manner of the first aspect or the third possible implementation manner of the first aspect, in a fourth possible implementation manner of the first aspect, the obtaining the frequency point of the second cell includes:

and the first cell receives the frequency point of the second cell sent by the coordinator.

With reference to the first possible implementation manner of the first aspect, in a fifth possible implementation manner of the first aspect, the preset policy includes: a first preset strategy or a second preset strategy, wherein,

The first preset policy includes: constructing an interference signal in the uplink signal received by the base station of the first cell as a statistical model, and performing interference reconstruction on the statistical model; the reconstructed interference signal is cancelled in a frequency domain;

The second preset strategy comprises: the base station of the first cell receives the demodulated soft bits or the decoded original bit stream sent by the base station of the second cell, and performs interference reconstruction on the demodulated soft bits or the decoded original bit stream according to the channel information of the interference signal in the uplink signal received by the base station of the first cell; and canceling the reconstructed interference signal in a frequency domain.

with reference to the fifth possible implementation manner of the first aspect, in a sixth possible implementation manner of the first aspect, the performing, by the base station of the first cell, interference pre-cancellation on the received uplink signal according to a preset policy to obtain an interference pre-cancellation signal includes:

if the energy values of the M sub-carriers are larger than a first threshold and smaller than a second threshold; performing interference pre-elimination according to the first preset strategy to obtain an interference pre-elimination signal;

And if the energy values of the M sub-carriers are greater than the second threshold, performing interference pre-elimination according to the second preset strategy to obtain an interference pre-elimination signal.

with reference to the fifth possible implementation manner of the first aspect or the sixth possible implementation manner of the first aspect, in a seventh possible implementation manner of the first aspect, the constructing an interference signal in the uplink signal received by the base station of the first cell as a statistical model, and performing interference reconstruction on the statistical model includes:

Constructing an interference signal in the uplink signal received by the base station of the first cell as a statistical model according to the spectrum characteristic of the second cell:

reconstructing the interference signal according to the statistical model and a reconstruction expression Y-H-X to obtain Y₁＝[y(0),y(1),...,y(K-1)]^Tk is the number of subcarriers needing cancellation, and H is a K x M order interference coefficient matrix;

Wherein n is_cAn index for the second cell carrier mapped to the first cell subcarrier.

With reference to the fifth possible implementation manner of the first aspect or the sixth possible implementation manner of the first aspect, in an eighth possible implementation manner of the first aspect, the performing interference reconstruction on the demodulated soft bits or the decoded original bit stream according to channel information of an interference signal in the uplink signal received by the base station of the first cell includes:

Estimating channel information of interference signals in the uplink signals received by the base station of the first cell;

processing the demodulated soft bits or decoded original bit stream into a baseband signal at the first cell sampling rate by oversampling;

converting the baseband signal into a frequency domain signal according to the number of the subcarriers of the first cell, and selecting M subcarriers from the frequency domain signal, and recording as: r ═ R (0), R (1),.., R (M-1)]^T；

reconstructing the demodulated soft bit or the decoded original bit stream according to a reconstruction formula Y ═ h ═ R to obtain Y₂and h is an interference coefficient matrix of K × M orders, and K is the number of subcarriers needing cancellation.

with reference to any one of the fifth possible implementation manner of the first aspect to the eighth possible implementation manner of the first aspect, in a ninth possible implementation manner of the first aspect, the canceling the reconstructed interference signal in the frequency domain includes:

judging the position relation between the carrier of the second cell and the center subcarrier of the first cell;

When the carrier of the second cell is positioned at the left side of the center subcarrier of the first cell, according to the formula x_1c(k)＝x(k)-Y(k-n_c-L) cancelling the reconstructed interfering signal; wherein Y is the reconstructed interference signal and is taken from Y₁Or Y₂；k＝n_c+L,...,n_c+ L + K-1; k is the number of subcarriers needing to be canceled; l is the distance between the first subcarrier to be cancelled and the center frequency point of the second cell;

When the carrier of the second cell is positioned at the right side of the center subcarrier of the first cell, according to a formula x_2c(k)＝x(k)-Y(k-n_c+ L + K), where Y is the reconstructed interference signal and is taken from Y₁or Y₂；k＝n_c-L-K,...,n_c-L-1; k is the number of subcarriers needing to be canceled; and L is the distance between the first subcarrier to be cancelled and the center frequency point of the second cell.

with reference to the second possible implementation manner of the first aspect, in a tenth possible implementation manner of the first aspect, the calculating energy values of M subcarriers including the second cell frequency point includes:

according to the formulaCalculating energy values of M subcarriers containing the frequency points of the second cell; wherein n is_cAnd mapping the second cell carrier to the index of the first cell subcarrier, wherein the RSSI is the energy value of the M subcarriers.

with reference to the first aspect, in an eleventh possible implementation manner of the first aspect, before performing interference pre-cancellation on a received uplink signal by the first cell according to a preset policy to obtain an interference pre-cancelled signal, the method includes:

Performing time domain windowing on each OFDM symbol in the uplink signal;

and adding the cyclic prefix of the OFDM symbol subjected to time domain windowing to the tail part of the corresponding OFDM symbol.

In a second aspect, an embodiment of the present invention provides an interference cancellation apparatus, where the apparatus is applied to a first cell, where the first cell has a second cell in a neighboring cell, where the first cell belongs to a first communication system, the second cell belongs to a second communication system, and there is a shared spectrum between the first cell and the second cell, and the apparatus includes:

An interference pre-elimination unit, configured to perform interference pre-elimination on the received uplink signal by the base station of the first cell according to a preset policy, so as to obtain an interference pre-elimination signal; wherein the uplink signal includes a first uplink signal sent by the user equipment in the first cell and a second uplink signal sent by the user equipment in the second cell;

And the interference elimination unit is used for carrying out interference elimination on the interference pre-elimination signal according to the channel response estimation value of the interference pre-elimination signal.

With reference to the second aspect, in a first possible implementation manner of the second aspect, the apparatus further includes:

An obtaining unit, configured to obtain an energy value of the second uplink signal;

The judging unit is used for judging whether the energy value of the second uplink signal is greater than a first threshold or not;

The interference pre-elimination unit is specifically configured to perform interference pre-elimination on the received uplink signal according to a preset strategy after the determination unit determines that the energy value of the second uplink signal is greater than a first threshold.

with reference to the first possible implementation manner of the second aspect, in a second possible implementation manner of the second aspect, the obtaining unit includes:

An obtaining module, configured to obtain a frequency point of the second cell;

and the calculating module is used for calculating energy values of M subcarriers including the frequency point of the second cell to obtain the energy value of the second uplink signal, wherein M is more than or equal to 12 and less than or equal to 60.

with reference to the second possible implementation manner of the second aspect, in a third possible implementation manner of the second aspect, the M subcarriers include 12 subcarriers selected by taking a frequency point of the second communication system as a center.

with reference to the second possible implementation manner of the second aspect or the third possible implementation manner of the second aspect, in a fourth possible implementation manner of the second aspect, the obtaining module is specifically configured to:

And receiving the frequency point of the second cell sent by the coordinator.

With reference to the first possible implementation manner of the second aspect, in a fifth possible implementation manner of the second aspect, the interference pre-cancellation unit includes a first pre-cancellation module or a second pre-cancellation module, where the first pre-cancellation module is configured to execute a first preset policy;

The first pre-cancellation module specifically includes: a first reconstruction module, configured to construct a statistical model of an interference signal in the uplink signal received by the base station of the first cell; performing interference reconstruction on the statistical model; the first cancellation module is used for canceling the reconstructed interference signal in a frequency domain;

the second pre-elimination module is used for executing a second preset strategy;

the second pre-cancellation module specifically includes: a second reconfiguration module, configured to receive the demodulated soft bits or the decoded original bit stream sent by the base station of the second cell, and perform interference reconfiguration on the demodulated soft bits or the decoded original bit stream according to channel information of an interference signal in the uplink signal received by the base station of the first cell; and the second cancellation module is used for canceling the interference signal subjected to interference reconstruction in the frequency domain.

With reference to the fourth possible implementation manner of the second aspect, in a sixth possible implementation manner of the second aspect, the determining unit is further configured to: judging whether the energy values of the M sub-carriers are larger than a first threshold and smaller than a second threshold or not;

The interference pre-elimination unit is further specifically configured to, after the energy values of the M subcarriers are greater than a first threshold and smaller than a second threshold, perform interference pre-elimination according to the first pre-elimination module to obtain an interference pre-elimination signal;

the interference pre-elimination unit is further specifically configured to perform interference pre-elimination according to the second pre-elimination module after the energy values of the M subcarriers are greater than the second threshold, so as to obtain an interference pre-elimination signal.

With reference to the fifth possible implementation manner of the second aspect or the sixth possible implementation manner of the second aspect, in a seventh possible implementation manner of the second aspect, the first reconstructing module is specifically configured to:

With reference to the fifth possible implementation manner of the second aspect or the sixth possible implementation manner of the second aspect, in an eighth possible implementation manner of the second aspect, the second reconfiguration module is specifically configured to:

Estimating channel information of an interference signal in the uplink signal received by the base station of the first cell;

converting the baseband signal into a frequency domain signal according to the number of the subcarriers of the first cell, and selecting M subcarriers from the frequency domain signal, and recording the M subcarriers as frequency domain signals：R＝[r(0),r(1),...,r(M-1)]^T；

Reconstructing the demodulated soft bit or the decoded original bit stream according to a reconstruction formula Y ═ h ═ R to obtain Y₂(ii) a And h is an interference coefficient matrix of K M orders, and K is the number of subcarriers needing cancellation.

With reference to any one possible implementation manner of the fifth possible implementation manner of the second aspect to the eighth possible implementation manner of the second aspect, in a ninth possible implementation manner of the second aspect, the first cancellation module and the second cancellation module are specifically configured to:

With reference to the second possible implementation manner of the second aspect, in a tenth possible implementation manner of the second aspect, the calculating module is specifically configured to:

with reference to the second aspect, in an eleventh possible implementation manner of the second aspect, the apparatus further includes a time domain windowing unit, where the time domain windowing unit is specifically configured to:

Performing time domain windowing on each OFDM symbol in the uplink signal;

The embodiment of the invention provides an interference elimination method, which is applied to a first cell, wherein the first cell is provided with a second cell adjacent to the first cell, the first cell belongs to a first communication system, the second cell belongs to a second communication system, a shared frequency spectrum exists between the first cell and the second cell, and a base station of the first cell carries out interference pre-elimination on a received uplink signal according to a preset strategy to obtain an interference pre-elimination signal; according to the method, the interference pre-elimination is carried out on the first cell and the second cell with shared frequency spectrum according to a preset strategy, the interference strength in the interference pre-elimination signal obtained after the interference is pre-eliminated is weakened, and the interference is further eliminated according to the channel response estimation value of the interference pre-elimination signal, so that the accuracy of the channel response estimation value of the interference pre-elimination signal is improved, the interference can be better eliminated or inhibited, the uplink bit error rate of the first communication system is reduced, and the uplink throughput rate of the first communication system is improved.

Drawings

in order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without creative efforts.

fig. 1 is a schematic diagram of dynamic sharing of GSM and LTE spectrum in the prior art;

fig. 2 is a schematic diagram of interference cancellation using interference suppression combining in the prior art;

Fig. 3 is a schematic view of an application scenario of an interference cancellation method according to an embodiment of the present invention;

fig. 4a is a first flowchart illustrating an interference cancellation method according to an embodiment of the present invention;

fig. 4b is a schematic mechanism diagram of performing time domain windowing by using an interference cancellation method according to an embodiment of the present invention;

fig. 5 is a flowchart illustrating a second interference cancellation method according to an embodiment of the present invention;

Fig. 6 is a first schematic structural diagram of an interference cancellation apparatus according to an embodiment of the present invention;

Fig. 7 is a schematic structural diagram of an interference cancellation apparatus according to an embodiment of the present invention;

Fig. 8 is a schematic structural diagram of an interference cancellation apparatus according to an embodiment of the present invention;

Fig. 9 is a fourth schematic structural diagram of an interference cancellation apparatus according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The technical scheme provided by the embodiment of the invention can be applied to various wireless communication networks, such as: a global system for mobile communication (GSM) system, a Code Division Multiple Access (CDMA) system, a Wideband Code Division Multiple Access (WCDMA) system, a Universal Mobile Telecommunications (UMTS) system, a General Packet Radio Service (GPRS) system, a Long Term Evolution (LTE) system, a long term evolution advanced (LTE-a) system, a Worldwide Interoperability for Microwave Access (WiMAX) system, and the like. The terms "network" and "system" are used interchangeably. The term "and/or" in the embodiment of the present invention is only one kind of association relationship describing an associated object, and indicates that three relationships may exist, for example, a and/or B may indicate: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" in the embodiment of the present invention generally indicates that the preceding and following related objects are in an "or" relationship.

In the embodiment of the present invention, the first communication system and the second communication system may be any two different wireless communication networks, and a shared spectrum exists between the two different wireless communication networks. For example, the first communication system and the second communication system may be a WCDMA system and an LTE system, a GSM system and an LTE system, a WCDMA system and a GSM system, and the like, respectively, which is not limited in this respect, because the principle and the processing manner of performing interference suppression or cancellation between any two different systems with shared spectrum are the same as those of the GSM system and the LTE system with shared spectrum, which is only exemplary, and the first communication system and the second communication system are respectively an LTE system and a GSM system in this embodiment of the present invention for example. And is not intended to have any particular meaning.

as shown in fig. 3, an application scenario in which an LTE system and a GSM system share a spectrum is provided, where a first cell belongs to the LTE system, a second cell belongs to the GSM system, and the first cell and the second cell are adjacent to each other. User Equipment (UE) at the edge of the second cell may generate uplink interference to the base station of the first cell.

in the embodiment of the present invention, a Base Station (BS) may be a device that communicates with a UE or other communication stations, such as a relay station, and the base station may provide communication coverage in a specific physical area. For example, the Base Station may specifically be a Base Transceiver Station (BTS) or a Base Station Controller (BSC) in GSM or CDMA; or Node B in UMTS (Node B, abbreviated as NB) or Radio Network Controller (RNC) in UMTS; the ue may also be an evolved Node B (ENB or eNodeB) in LTE; alternatively, the present invention is not limited to this, and the present invention may be other access network devices that provide access services in a wireless communication network. For example, in the application scenario shown in fig. 3, the base station of the first cell may be an eNodeB, and the base station of the second cell may be a BTS.

in the embodiments of the present invention, the UEs may be distributed throughout the wireless network, and each UE may be static or mobile. A UE may be referred to as a terminal (terminal), a mobile station (mobile station), a subscriber unit (subscriber unit), a station (station), etc. The UE may be a cellular phone (cellular phone), a Personal Digital Assistant (PDA), a wireless modem (modem), a wireless communication device, a handheld device (hand-held), a laptop computer (laptop computer), a cordless phone (cordless phone), a Wireless Local Loop (WLL) station, or the like. When the UE is applied to M2M mode communication, the UE may be referred to as an M2M terminal, and specifically may be a smart meter, a smart appliance, or the like supporting M2M communication.

As shown in fig. 4, an embodiment of the present invention provides an interference cancellation method, which is applied to a first cell, where a second cell is a neighboring cell of the first cell, where the first cell belongs to a first communication system, the second cell belongs to a second communication system, and a shared spectrum exists in the first communication system and the second communication system (as shown in fig. 3), and the method includes:

And S1, the base station of the first cell performs interference pre-elimination on the received uplink signal according to a preset strategy to obtain an interference pre-elimination signal.

and S2, carrying out interference elimination on the interference pre-elimination signal according to the channel response estimation value of the interference pre-elimination signal.

The interference cancellation method provided by the embodiment of the invention can be executed by an eNodeB.

The embodiment of the invention provides an interference elimination method, which is characterized in that interference pre-elimination is carried out on a first cell and a second cell with shared frequency spectrum according to a preset strategy, because the interference strength in an interference pre-elimination signal obtained after the interference is pre-eliminated is weakened, the interference is further eliminated according to a channel response estimation value of the interference pre-elimination signal, the accuracy of the channel response estimation value of the interference pre-elimination signal is improved, the interference can be better eliminated or suppressed, the uplink error rate of a first communication system is reduced, and the uplink throughput rate of the first communication system is improved.

illustratively, the first communication system is an LTE system, and the second communication system is a GSM system.

as shown in fig. 3, the uplink signals may include a first uplink signal transmitted by a UE1 located in a first cell of the LTE system and a second uplink signal transmitted by a UE2 located in a second cell of the GSM system, where for the first cell, the second uplink signal received by the first cell is an interference signal.

in a preferred example of the embodiment of the present invention, before step S1, the method further includes:

s3, acquiring an energy value of the second uplink signal;

the energy value of the second uplink signal may be represented by a sum of energy values of M subcarriers in the second uplink signal.

The energy value of the second uplink signal may be obtained in various manners, which is not limited in the embodiment of the present invention, and is only exemplary, for example, the energy value of the second uplink signal may be obtained specifically through the following steps a1-a 2:

A1, acquiring the frequency point of the second cell;

There are various ways to acquire the frequency point of the second cell, which are not limited in this embodiment of the present invention, but are merely exemplary, and the embodiment of the present invention may acquire the frequency point of the second cell through the following two possible ways.

a first possible implementation includes:

Eco (coordinator) acquires a frequency point of the second cell;

And sending the received frequency point of the second cell to the base station of the first cell by the Eco.

A second possible implementation includes:

a base station of a first cell sends a request to an Eco, wherein the request is used for indicating the Eco to acquire a frequency point of a second cell;

and the Eco acquires the frequency point of the second cell according to the request and feeds the frequency point back to the base station of the first cell.

The Eco is connected to an MME (Mobility Management Entity), the S-GW, a base station controller corresponding to the second cell, and a first communication system corresponding to the first cell, respectively, and is configured to provide cooperative service processing between the second communication system and the first communication system. The first communication system may be an LTE system, and the second communication system may be a GSM/UMTS system.

And the base station controller corresponding to the second cell acquires the frequency point of the second cell from the MME and reports the frequency point of the second cell to Eco.

A2, calculating the energy values of M subcarriers containing the frequency points of the second cell, wherein M is more than or equal to 12 and less than 60.

preferably, in order to reduce the complex amount of system operation, in practical operation, 40 subcarriers are generally selected, and further preferably, the M subcarriers are: and 12 subcarriers selected by taking the frequency point of the second cell as a center according to a preset bandwidth.

The embodiment of the present invention does not limit the specific bandwidth value of the preset bandwidth, and can be set as needed in practical application.

For example, an embodiment of the present invention provides a formula for calculating energy values of M subcarriers containing the frequency point of the second cell:

Wherein n is_cAnd mapping the second cell carrier to the index of the first cell subcarrier, wherein the RSSI is the energy value of the M subcarriers.

For example, when the M subcarriers are: according to the preset bandwidth, when 12 subcarriers are selected by taking the frequency point of the second cell as the center, the energy values of the 12 subcarriers are as follows:

RSSI＝|x(n_c-5)|²+|x(n_c-4)|²+...+|x(n_c)|²+|x(n_c+1)|²+|x(n_c+2)|²+...+|x(n_c+6)|²。

And S4, if the energy value of the second uplink signal is greater than a first threshold, the base station of the first cell performs interference pre-elimination on the received uplink signal according to a preset strategy.

for example, when the signal quality requirement of the first cell is relatively low, the first threshold may be set to be relatively high, and when the signal quality requirement of the first cell is relatively high, the first threshold may be set to be relatively low, preferably, the first threshold in the embodiment of the present invention is-95 dBm.

because the strength of the interference signal has a large influence on the channel response estimation value of the interference signal, when the interference signal is weak, the method for eliminating the interference signal according to the channel response estimation value of the interference signal has a good effect. When the interference signal is strong, the method for eliminating the interference signal according to the channel response estimation value of the interference signal is poor in effect. By setting the first threshold, on one hand, when the energy value of the second uplink signal (interference signal) is greater than the first threshold, the embodiment of the invention can reduce the energy value of the second uplink signal and improve the accuracy of the channel response estimation value by performing interference pre-cancellation on the uplink signal through S1, so that the interference cancellation and suppression can be better performed on the second uplink signal received by the first cell; on the other hand, when the energy value of the second uplink signal (the interference signal) is less than or equal to the first threshold, the existing interference cancellation technology (for example, the IRC technology) may be directly adopted to cancel the second uplink signal, which may reduce the complexity of the interference cancellation method, reduce the cost, and improve the efficiency.

The IRC technology comprises the following specific steps: acquiring an autocorrelation matrix of the uplink signal; estimating a covariance matrix of the interference signal through an autocorrelation matrix of the uplink signal; and eliminating or suppressing the interference signal between the first communication system and the second communication system by an interference suppression combining technology according to the covariance matrix of the interference signal.

The key point of the IRC technology is to calculate the covariance matrix of the interference signal, the accuracy of the covariance matrix estimation of the interference signal can greatly affect the performance of the IRC technology, and the specific calculation formula of the covariance matrix of the interference signal is as follows:

the LTE system receives signals:

Covariance matrix of interference signal:

Therefore, the strength of the interference signal has a great influence on the accuracy of the covariance matrix estimation of the interference signal, and when the interference signal is strong, the accuracy of the covariance matrix estimation of the interference signal is deteriorated. According to the embodiment of the invention, the interference strength of the interference signal in the uplink signal is weakened after the interference pre-elimination is carried out on the uplink signal received by the base station of the first cell according to the preset strategy, and then the interference covariance matrix is calculated through the IRC technology.

In another example of the embodiment of the present invention, the preset policy may include: the first preset strategy or the second preset strategy will be described below.

1. the first preset policy includes: constructing an interference signal in the uplink signal received by the base station of the first cell as a statistical model, and performing interference reconstruction on the statistical model; and canceling the reconstructed interference signal in a frequency domain.

There are various ways to construct the interference signal in the interference pre-cancellation signal as the statistical model, which is not limited in this embodiment of the present invention, for example, the interference signal in the interference pre-cancellation signal may be constructed as the statistical model through a1-b 1:

a1, constructing the interference signal in the uplink signal received by the base station of the first cell as a statistical model according to the spectrum characteristic of the second cell:

M is selected by taking the frequency point of a second cell as the center in N frequency domain data obtained by carrying out frequency domain conversion on the uplink signal received by the first cell;

b1, reconstructing the interference signal according to the statistical model and a reconstruction expression Y-H-X to obtain Y₁＝[y(0),y(1),...,y(K-1)]^TK is the number of subcarriers needing cancellation, and H is a K x M order interference coefficient matrix;

H is an interference coefficient matrix obtained by using a channel estimation algorithm according to the spectral characteristic of the second cell, for example, an MMSE (Minimum Mean Square Error) algorithm and an LS algorithm.

In order to reduce the complexity of the interference cancellation method, in a specific implementation process, an interference coefficient matrix H corresponding to an interference signal in the uplink signal received by the base station of the first cell may be calculated in advance according to a spectral characteristic of a second cell, and then the interference coefficient matrix H is stored, and when an interference signal in the uplink signal received by the base station of the first cell needs to be reconstructed, the base station of the first cell may directly read the interference coefficient matrix H and reconstruct the interference signal according to a reconstruction expression Y ═ H × X.

2. the second preset strategy comprises: the base station of the first cell receives the demodulated soft bits or the decoded original bit stream sent by the base station of the second cell, and performs interference reconstruction on the demodulated soft bits or the decoded original bit stream according to the channel information of the interference signal in the uplink signal received by the base station of the first cell; and canceling the reconstructed interference signal in a frequency domain.

The embodiment of the present invention is not limited to this, and specifically, the method may perform interference reconstruction on the demodulated soft bits or the decoded original bit stream according to the channel information of the interference signal in the uplink signal received by the base station of the first cell, for example, the method may perform interference reconstruction on the demodulated soft bits or the decoded original bit stream according to the channel information of the interference signal in the uplink signal received by the base station of the first cell through a2-d 2:

a2, estimating channel information of interference signals in the uplink signals received by the base station of the first cell;

the channel information of the interference signal refers to a channel attribute of the interference signal causing interference to the first cell by the second cell in the communication link in the wireless communication field. I.e. signal Scattering (Scattering) of the channel of the second cell, fading (fading), distance fading (power fading), etc.

there are various ways to estimate channel information of an interference signal in the uplink signal received by the base station of the first cell, and an exemplary embodiment of the present invention is not limited herein, and the channel information of the interference signal in the uplink signal received by the base station of the first cell may be estimated in the following ways:

three known channel models based on the LTE system, for example, an ETU (Extended Typical Urban channel model), an EVA (Extended Vehicular channel model), and an EPA (Extended behavioral channel model) obtain three kinds of channel information, and store the three kinds of channel information, and then the first cell directly reads corresponding channel information when it is necessary to estimate channel information of an interference signal in the uplink signal received by the base station of the first cell according to a delay spread value measured by the LTE system.

b2, processing the demodulated soft bits or decoded original bit stream into a baseband signal at the first cell sampling rate through oversampling;

In the embodiment of the present invention, the base station of the second cell transmits the demodulated soft bits or the decoded original bit stream to the base station of the first cell, the base station of the first cell processes the soft bits or the bit stream into a baseband signal of the second cell according to the principle of the UE transmitter of the second cell, and samples the demodulated soft bits or the decoded original bit stream to the sampling rate of the first cell by using the sampling filter, so as to obtain the baseband signal.

c2, converting the baseband signal into a frequency domain signal according to the number of the sub-carriers of the first cell, and selecting M middle sub-carriers from the frequency domain signal, and recording as:

R＝[r(0),r(1),...,r(M-1)]^T；

In this embodiment of the present invention, the baseband signal may be converted into a frequency domain signal in multiple ways, and no signal is performed for this, for example, the baseband signal may be converted into a frequency domain signal that is consistent with the number of subcarriers of the first cell through Fast Fourier Transform (FFT) according to the number of subcarriers of the first cell in the embodiment of the present invention.

d2 according to weightReconstructing the demodulated soft bit or the decoded original bit stream according to a formula Y ═ h ═ R to obtain Y₂(ii) a And h is an interference coefficient matrix of K M orders, and K is the number of subcarriers needing cancellation.

In another preferred embodiment of the present invention, the performing, by the first cell, interference pre-cancellation on the received uplink signal according to a preset policy to obtain an interference pre-cancelled signal may include:

For example, when the signal quality requirement of the first cell is relatively low, the second threshold may be set to be relatively high, and when the signal quality requirement of the first cell is relatively high, the second threshold may be set to be relatively low, preferably, the second threshold in the embodiment of the present invention is-70 dBm.

By setting the second threshold, on one hand, when the energy value of the second uplink signal (the energy value of the interference signal) is greater than the first threshold and less than the second threshold, the embodiment of the invention can perform interference pre-cancellation on the uplink signal received by the base station of the first cell through a first preset strategy to reduce the energy of the second uplink signal in the uplink signal, thereby improving the accuracy of the channel response estimation value, and thus better eliminating the second uplink signal received by the base station of the first cell; on the other hand, when the energy value of the second uplink signal is greater than the second threshold, the base station of the first cell may perform interference cancellation and suppression on the uplink signal by using a second preset strategy.

it should be noted that, when the uplink signal received by the base station of the first cell includes the second uplink signal of the base station of the second cell, the preset strategy can be selected by setting the first threshold and the second threshold, or any one of the preset strategies can be directly used for eliminating and suppressing the second uplink signal in the uplink signals, for example, the base station of the first cell may fixedly use the first preset strategy to cancel and suppress the second uplink signal in the uplink signal received by the base station of the first cell, may also fixedly use the second preset strategy to cancel and suppress the second uplink signal in the uplink signal received by the base station of the first cell, and may also cancel and suppress the second uplink signal in the uplink signal received by the base station of the first cell after the first preset strategy and the second preset strategy are concatenated, which is not limited in the embodiment of the present invention.

in the first preset strategy and the second preset strategy, the canceling the reconstructed interference signal includes:

And judging the position relation between the carrier of the second cell and the center subcarrier of the first cell.

when the carrier of the second cell is positioned at the left side of the center subcarrier of the first cell, according to the formula x_1c(k)＝x(k)-Y(k-n_c-L) cancelling the reconstructed interfering signal; wherein k is n_c+L,...,n_c+ L + K-1; y is the reconstructed interference signal and is taken from Y₁or Y₂(ii) a K is the number of subcarriers needing to be canceled; l is the distance between the first subcarrier to be cancelled and the center frequency point of the second cell;

for example, the embodiment of the present invention may compare the relationship between the frequency point of the second communication system and the frequency point of the first communication system, if the frequency point of the second communication system is smaller than the frequency point of the first communication system, the carrier of the first cell is located on the left of the center subcarrier of the first cell, and if the frequency point of the second communication system is larger than the frequency point of the first communication system, the carrier of the first cell is located on the right of the center subcarrier of the first cell.

Wherein, the embodiment of the present invention does not limit the specific value of K, and when the energy of the M subcarriers is relatively large, i.e. the interference signal of the second cell to the first cell is very strong, the specific value of K may be set to be relatively large, that is, the energy of the second uplink signal can be weakened by increasing the number of cancellation second cell subcarriers, when the energy of the M subcarriers is smaller, i.e. the interference signal of the second cell to the first cell is weak, the specific value of K may be set to be small, i.e., the energy of the second uplink signal can be attenuated by canceling the small number of subcarriers of the second cell, since the number of user equipments at the edge of each second cell is not necessarily the same, the strength of the interfering signal to the first cell is not limited, and the specific value of K may be determined according to actual situations.

In order to better eliminate the interference signal of the second cell received by the base station of the first cell at a position where the first cell is far away from the frequency point of the second cell, the embodiment of the present invention may further include:

Performing time domain windowing on each OFDM symbol in the uplink signal;

the time domain windowing may be performed on each OFDM (Orthogonal Frequency Division Multiplexing) symbol in the uplink signal by using a time domain windowing algorithm (e.g., Nyquist window, or trapezoidal window), that is, the time domain windowing is performed on each received OFDM symbol.

As shown in fig. 4b, since the trapezoidal window filters a part of the useful signal at the tail of each OFDM symbol, and CP (Cyclic Prefix) is a copy of the tail, the CP after time domain windowing is added to the tail of each OFDM symbol for combination, so as to compensate the effect of the trapezoidal window on the useful signal, the embodiment of the present invention further includes:

preferably, in the embodiment of the present invention, before the base station of the first cell performs interference pre-cancellation on the received uplink signal according to a preset policy to obtain the interference pre-cancelled signal, frequency domain conversion is further performed on the uplink signal.

As shown in fig. 5, the interference cancellation method will be described below by using a specific embodiment.

The embodiment of the present invention may be applied to any two different wireless communication networks, and a shared spectrum exists between the two different wireless communication networks, which is only an example, and the embodiment of the present invention is still described with reference to an application scenario that an LTE system and a GSM system have a shared spectrum, which is shown in fig. 3. The LTE system and the GSM system may both be configured with multiple cells, and in the embodiment of the present invention, only the first cell and the second cell are taken as an example for description;

600. Performing time domain windowing on each OFDM symbol in the uplink signal; adding the cyclic prefix of the OFDM symbol subjected to time domain windowing to the tail part of the corresponding OFDM symbol;

601. The base station of the first cell carries out frequency domain conversion on the received uplink signal;

The uplink signals may include a first uplink signal sent by a user equipment 1 located in a first cell of the LTE system and a second uplink signal sent by a user equipment 2 located in an edge of a second cell of the GSM system, where the second uplink signal sent by the user equipment 2 located in the edge of the second cell may include all second uplink signals that may cause interference to the first cell;

the frequency domain conversion module may perform frequency domain conversion on the uplink signal, and may also perform frequency domain conversion on the uplink signal in other forms.

602. Judging whether the energy value of the second uplink signal received by the base station of the first cell is greater than a first threshold, if so, executing step 603, and if not, executing step 604;

603. judging whether the energy value of the second uplink signal is smaller than a second threshold, if so, executing a step 605, and if not, executing a step 606;

For the method of determining whether the energy value of the second uplink signal is smaller than the second threshold, reference may be made to the above embodiments, and details of the present invention are not repeated herein.

604. and eliminating the interference of the second uplink signal by adopting an interference suppression and combination technology.

the specific process of the interference suppression combining technique can be as described in the above embodiments, and the details of the present invention are not repeated herein.

605. Performing interference pre-elimination on the second uplink signal by adopting a first preset strategy, and then executing a step 607;

for a specific implementation of the first preset policy, reference may be made to the above embodiments, and the present invention is not described herein again.

606. Performing interference pre-elimination on the uplink signal by adopting a second preset strategy, and then executing a step 607;

for a specific implementation of the second preset policy, reference may be made to the above embodiments, and the present invention is not described herein again.

607. Canceling the reconstructed interference in the frequency domain, and then executing step 604;

for a specific method for canceling the reconstructed interference in the frequency domain, reference may be made to the above embodiments, and details of the present invention are not repeated herein.

the embodiment of the invention provides an interference elimination method, which selects a proper preset strategy for interference pre-elimination by judging the energy value of a second cell, since the interference signal brought to the first cell by the second cell selects the preset strategy according to the energy value of the second cell, the strength of the interference signal sent by the second cell to the first cell can be effectively weakened, so that the interference signal after pre-elimination is eliminated through the interference suppression combination technology, because the strength of the interference signal from the second cell to the first cell in the interference pre-elimination signal obtained after the interference is pre-eliminated is weakened, and the interference is further eliminated according to the channel response estimation value of the interference pre-elimination signal, the accuracy of the channel response estimation value of the interference pre-elimination signal is improved, therefore, the interference can be better eliminated or suppressed, and the uplink error rate of the first communication system is reduced, so that the uplink throughput rate of the first communication system is improved.

embodiments of the present invention provide an interference cancellation apparatus, where each functional unit in the interference cancellation apparatus corresponds to the method of the interference cancellation apparatus in the foregoing embodiments, and reference may be specifically made to the description in the foregoing embodiments of the present invention, and details of the embodiments of the present invention are not repeated herein. As shown in fig. 6, the interference cancellation apparatus is applied to a first cell, where the first cell has a second cell neighboring to a first cell, where the first cell belongs to a first communication system, the second cell belongs to a second communication system, and there is a shared spectrum between the first cell and the second cell, and the apparatus includes:

an interference pre-cancellation unit 201, configured to perform interference pre-cancellation on the received uplink signal by the base station of the first cell according to a preset policy, so as to obtain an interference pre-cancellation signal; wherein the uplink signal includes a first uplink signal sent by the user equipment 1 in the first cell and a second uplink signal sent by the user equipment 2 in the second cell;

an interference cancellation unit 202, configured to perform interference cancellation on the interference pre-cancelled signal according to the channel response estimation value of the interference pre-cancelled signal.

The embodiment of the invention provides an interference elimination device, which selects a proper preset strategy for interference pre-elimination by judging the energy value of a second cell, since the interference signal brought to the first cell by the second cell selects the preset strategy according to the energy value of the second cell, the strength of the interference signal sent by the second cell to the first cell can be effectively weakened, so that the interference signal after pre-elimination is eliminated through the interference suppression combination technology, because the strength of the interference signal from the second cell to the first cell in the interference pre-elimination signal obtained after the interference is pre-eliminated is weakened, and the interference is further eliminated according to the channel response estimation value of the interference pre-elimination signal, the accuracy of the channel response estimation value of the interference pre-elimination signal is improved, therefore, the interference can be better eliminated or suppressed, and the uplink error rate of the first communication system is reduced, so that the uplink throughput rate of the first communication system is improved.

Optionally, as shown in fig. 7, the interference pre-cancellation unit 201 further includes:

An obtaining unit 203, configured to obtain an energy value of the second uplink signal;

A determining unit 204, configured to determine whether the energy value of the second uplink signal is greater than a first threshold, and after the determining unit 204 determines that the energy value of the second uplink signal is greater than the first threshold, the interference pre-cancellation unit 201 performs interference pre-cancellation on the uplink signal received by the base station of the first cell according to a preset policy, to obtain an interference pre-cancellation signal.

preferably, as shown in fig. 7, the obtaining unit 203 includes:

an obtaining module 2031, configured to obtain a frequency point of the second cell;

A calculating module 2032, configured to calculate energies of M subcarriers including the second cell frequency point, to obtain an energy value of the second uplink signal, where M is greater than or equal to 12 and less than or equal to 60.

Preferably, the M subcarriers include 12 subcarriers selected by centering on a frequency point of the second communication system.

Preferably, the obtaining module 2031 is specifically configured to:

and receiving the frequency point of the second cell sent by the Eco.

optionally, as shown in fig. 8, the interference pre-cancellation unit 201 includes a first pre-cancellation module 2011 and a second pre-cancellation module 2012;

it should be noted that the interference pre-cancellation unit 201 may only include the first pre-cancellation module 2011, or only include the second pre-cancellation module, as shown in fig. 9, or include both the first pre-cancellation module and the second pre-cancellation module, and may be set according to an energy value of the second uplink signal in a specific implementation process, which is not limited herein.

The first pre-elimination module 2011 is configured to execute a first pre-set policy;

as shown in fig. 9, the first pre-elimination module 2011 specifically includes: a first reconstruction module, configured to construct a statistical model of an interference signal in the uplink signal received by the base station of the first cell; performing interference reconstruction on the statistical model; the first cancellation module is used for canceling the reconstructed interference signal in a frequency domain;

as shown in fig. 9, the second pre-elimination module specifically includes: a second reconfiguration module, configured to receive the demodulated soft bits or the decoded original bit stream sent by the base station of the second cell, and perform interference reconfiguration on the demodulated soft bits or the decoded original bit stream according to channel information of an interference signal in the uplink signal received by the base station of the first cell; and the second cancellation module is used for canceling the reconstructed interference signal in the frequency domain.

Preferably, the judging unit 204 is further configured to: judging whether the energy values of the M sub-carriers are larger than a first threshold and smaller than a second threshold or not;

the interference pre-cancellation unit 201 is further specifically configured to perform interference pre-cancellation according to the first pre-cancellation module 2011 after the energy values of the M subcarriers are greater than a first threshold and smaller than a second threshold, so as to obtain an interference pre-cancellation signal;

The interference pre-cancellation unit 201 is further specifically configured to, after the energy values of the M subcarriers are greater than the second threshold, perform interference pre-cancellation according to the second pre-cancellation module 2012 to obtain an interference pre-cancellation signal.

Preferably, the first reconstruction module 20121 is specifically configured to:

In order to reduce the complexity of the interference cancellation apparatus, the interference coefficient matrix H may be pre-calculated according to the spectral characteristics of the second cell during actual operation, and stored in a memory, and may be read as needed by reading the value stored in the memory, where the memory may include a volatile memory (such as a random-access memory (RAM); the memory may also include a non-volatile memory (ROM), such as a read-only memory (read-only memory), a flash memory (flash memory), a hard disk (HDD) or a solid-state drive (SSD); the memory may also comprise a combination of memories of the above kind, illustratively the memory of an embodiment of the invention being a random access memory.

preferably, the second reconfiguration module 20121 is specifically configured to:

The channel information of the interference signal in the uplink signal received by the base station of the first cell may be estimated in the following manner, for example: three kinds of channel information are obtained based on three known channel models of an LTE system, such as ETU, EVA and EPA, and are stored in a memory, and then a first cell directly reads the channel information stored in the memory when the channel information of an interference signal in an uplink signal received by the first cell needs to be estimated according to a delay spread value measured by the LTE system. The memory may include a volatile memory (RAM), such as a random-access memory (RAM); the memory may also include a non-volatile memory (ROM), such as a read-only memory (read-only memory), a flash memory (flash memory), a hard disk (HDD), or a solid-state drive (SSD); the memory may also comprise a combination of memories of the above kind, illustratively the memory of an embodiment of the invention being a random access memory.

preferably, the first cancellation module 20112 and the second cancellation module 20122 are specifically configured to:

It should be noted that, in a specific implementation process, the first cancellation module 20112 and the second cancellation module 20122 may be configured as an interference cancellation module.

Preferably, the calculating module 2032 is specifically configured to:

preferably, the interference cancellation apparatus 20 further includes a time domain windowing unit, and the time domain windowing module is specifically configured to:

Performing time domain windowing on each OFDM symbol in the uplink signal;

preferably, the interference cancellation apparatus 20 further includes a frequency domain conversion unit, configured to perform frequency domain conversion on the uplink signal.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.

Claims

1. an interference cancellation method applied to a first cell having a second cell neighboring a first cell, wherein the first cell belongs to a first communication system, wherein the second cell belongs to a second communication system, and wherein a shared spectrum exists between the first cell and the second cell, the method comprising:

according to the channel response estimation value of the interference pre-elimination signal, carrying out interference elimination on the interference pre-elimination signal;

Wherein the preset strategy comprises: a first preset strategy or a second preset strategy, wherein,

2. The method of claim 1, wherein before the base station of the first cell performs interference pre-cancellation on the received uplink signal according to a preset strategy to obtain an interference pre-cancelled signal, the method further comprises:

Acquiring an energy value of the second uplink signal;

3. the method of claim 2, wherein the obtaining the energy value of the second uplink signal comprises:

acquiring a frequency point of the second cell;

4. the method of claim 3, wherein the M subcarriers comprise 12 subcarriers selected centered around a frequency point of the second communication system.

5. The method according to claim 3 or 4, wherein the obtaining the frequency point of the second cell comprises:

6. The method of claim 3, wherein the interference pre-cancellation is performed on the received uplink signal by the base station of the first cell according to a preset policy to obtain an interference pre-cancelled signal, and the method comprises:

7. the method according to claim 3 or 6, wherein the constructing the interference signal in the uplink signal received by the base station of the first cell as a statistical model, and performing interference reconstruction on the statistical model comprises:

wherein n is_cAn index for the second cell carrier mapped to the first cell subcarrier;Respectively M subcarrier signals selected by taking the frequency point of the second communication system as a center; [ y (0), y (1),.. -, y (K-1)]^TRespectively K reconstructed interference signals.

8. The method according to claim 1 or 6, wherein the performing interference reconstruction on the demodulated soft bits or the decoded original bit stream according to the channel information of the interference signal in the uplink signal received by the base station of the first cell comprises:

9. the method of claim 7, wherein the canceling the reconstructed interference signal in the frequency domain comprises:

When the carrier of the second cell is positioned at the left side of the center subcarrier of the first cell, according to the formula x_1c(k)＝x(k)-Y(k-n_c-L) cancelling the reconstructed interfering signal; wherein k is n_c+L，...，n_c+ L + K-1; y is the reconstructed interference signal and is taken from Y₁(ii) a K is the number of subcarriers needing to be canceled; l is the distance between the first subcarrier to be cancelled and the center frequency point of the second cell; x (k) is the first cell center subcarrier signal;

When the carrier of the second cell is positioned at the right side of the center subcarrier of the first cell, according to a formula x_2c(k)＝x(k)-Y(k-n_c+ L + K), where Y is the reconstructed interference signal and is taken from Y₁；k＝n_c-L-K,...,n_c-L-1; k is the number of subcarriers needing to be canceled; and L is the distance between the first subcarrier to be cancelled and the center frequency point of the second cell.

10. the method of claim 8, wherein canceling the reconstructed interference signal in the frequency domain comprises:

When the carrier of the second cell is positioned at the left side of the center subcarrier of the first cell, according to the formula x_1c(k)＝x(k)-Y(k-n_c-L) cancelling the reconstructed interfering signal; wherein k is n_c+L，...，n_c+ L + K-1; y is the reconstructed interference signal and is taken from Y₂(ii) a K is the number of subcarriers needing to be canceled; l is the distance between the first subcarrier to be cancelled and the center frequency point of the second cell; x (k) is the first cell center subcarrier signal;

when the carrier of the second cell is positioned at the right side of the center subcarrier of the first cell, according to a formula x_2c(k)＝x(k)-Y(k-n_c+ L + K), where Y is the reconstructed interference signal and is taken from Y₂；k＝n_c-L-K,...,n_c-L-1; k is the number of subcarriers needing to be canceled; and L is the distance between the first subcarrier to be cancelled and the center frequency point of the second cell.

11. The method according to claim 3, wherein said calculating energy values of M subcarriers containing the second cell frequency point comprises:

according to the formulaCalculating energy values of M subcarriers containing the frequency points of the second cell; wherein n is_cMapping the second cell carrier to the index of the first cell subcarrier, wherein RSSI is the energy value of the M subcarriers;Respectively in said second communication systemAnd M subcarrier signals selected by taking the frequency point as the center.

12. The method of claim 1, wherein before the base station of the first cell performs interference pre-cancellation on the received uplink signal according to a preset strategy to obtain an interference pre-cancelled signal, the method comprises:

Performing time domain windowing on each OFDM symbol in the uplink signal;

13. an interference cancellation apparatus applied to a first cell, the first cell having a second cell neighboring to a first cell, wherein the first cell belongs to a first communication system, the second cell belongs to a second communication system, and a shared spectrum exists between the first cell and the second cell, the apparatus comprising:

An interference elimination unit, configured to perform interference elimination on the interference pre-elimination signal according to a channel response estimation value of the interference pre-elimination signal;

The interference pre-elimination unit comprises a first pre-elimination module or a second pre-elimination module, and the first pre-elimination module is used for executing a first preset strategy;

14. The apparatus of claim 13, further comprising:

the interference pre-elimination unit is specifically configured to, after the determination unit determines that the energy value of the second uplink signal is greater than a first threshold, perform interference pre-elimination on the uplink signal received by the base station of the first cell according to a preset strategy by the interference pre-elimination unit.

15. The apparatus of claim 14, wherein the obtaining unit comprises:

An obtaining module, configured to obtain a frequency point of the second cell;

16. the apparatus of claim 15, wherein the M subcarriers comprise 12 subcarriers selected centered around a frequency point of the second communication system.

17. the apparatus according to claim 15 or 16, wherein the obtaining module is specifically configured to:

and receiving the frequency point of the second cell sent by the coordinator.

18. The apparatus of claim 15, wherein the determining unit is further configured to: judging whether the energy values of the M sub-carriers are larger than a first threshold and smaller than a second threshold or not;

19. the apparatus according to claim 15 or 18, wherein the first reconstruction module is specifically configured to:

Wherein n is_cAn index for the second cell carrier mapped to the first cell subcarrier;Respectively M subcarrier signals selected by taking the frequency point of the second communication system as a center; [ y (0), y (1),.. -, y (K-1)]^Trespectively K reconstructed stemsAnd (4) disturbing the signal.

20. The apparatus according to claim 15 or 18, wherein the second reconstruction module is specifically configured to:

Reconstructing the demodulated soft bits or the decoded original bit stream according to a reconstruction formula Y-R h₂And h is an interference coefficient matrix of K × M orders, and K is the number of subcarriers needing cancellation.

21. The apparatus of claim 19, wherein the first cancellation module and the second cancellation module are specifically configured to:

When the carrier of the second cell is located at the left side of the center subcarrier of the first cell, n is set according to the formula_c+L,...,n_c+ L + K-1 eliminates the reconstructed interference signal; wherein k is n_c+L，...，n_c+ L + K-1; y is the reconstructed interference signal and is taken from Y₁(ii) a K is the number of subcarriers needing to be canceled; l is the distance between the first subcarrier to be cancelled and the center frequency point of the second cell; x (k) is the first cell center subcarrier signal;

22. the apparatus of claim 20, wherein the first cancellation module and the second cancellation module are specifically configured to:

When the carrier of the second cell is located at the left side of the center subcarrier of the first cell, n is set according to the formula_c+L,...,n_c+ L + K-1 eliminates the reconstructed interference signal; wherein k is n_c+L，...，n_c+ L + K-1; y is the reconstructed interference signal and is taken from Y₂(ii) a K is the number of subcarriers needing to be canceled; l is the distance between the first subcarrier to be cancelled and the center frequency point of the second cell; x (k) is the first cell center subcarrier signal;

23. The apparatus of claim 15, the computing module to:

according to the formulaCalculating energy values of M subcarriers containing the frequency points of the second cell; wherein n is_cmapping the second cell carrier to the index of the first cell subcarrier, wherein RSSI is the energy value X of the M subcarriers;respectively M subcarrier signals selected with the frequency point of the second communication system as the center.

24. The apparatus according to claim 13, further comprising a time domain windowing unit, the time domain windowing unit being specifically configured to:

Performing time domain windowing on each OFDM symbol in the uplink signal;