CN108809872B - An interference management method based on interference regeneration in a wireless communication system - Google Patents

Abstract

The invention belongs to the technical field of wireless communication, and discloses an interference management method based on interference regeneration in a wireless communication system. Transmitters share channel state information and data information, and a transmitter corresponding to an interfered receiver constructs a structure according to the information. Interference regeneration signal; the transmitter corresponding to the interfered receiver sends the interference regeneration signal, and the interfered receiver performs matched filtering on the received mixed signal composed of the interference and the interference regeneration signal, and reproduces the desired data from the interference. The invention has the advantages of converting interference into desired signals, utilizing the energy of the interference, and improving the spectrum efficiency of the interfered receiver, and can be used to solve the interference problem in wireless communication. An IRC signal for interference regeneration, using the interaction between wireless signals, after filtering, regenerates the desired signal of the PUE from the interference.

Description

An interference management method based on interference regeneration in a wireless communication system

technical field

The invention belongs to the technical field of wireless communication, and in particular relates to an interference management method based on interference regeneration in a wireless communication system.

Background technique

At present, the prior art commonly used in the industry is as follows: with the development of wireless communication technology, the wireless communication network will include various types of communication systems and carry diverse user services. With the layering and isomerization of network structure and the introduction of various dynamic spectrum sharing technologies, wireless interference has become one of the key factors restricting network performance. Therefore, the importance of interference management techniques is growing. All along, people have used resource allocation, such as time division multiple access (TDMA), frequency division multiple access (FDMA), code division multiple access (CDMA), etc., or signal processing means, such as interference alignment (IA), zero-forcing beamforming (ZFBF) realizes the control of the negative effects caused by the disturbance by changing the characteristics of the disturbance. The prior art—interference-oriented management of interference, on the basis of interference neutralization (IN) and interference alignment (IA), an interference-oriented (IS) mechanism is designed, using the interaction between wireless signals to construct an interference-oriented signal, The interference observed by the interfered receiver is directed in a direction orthogonal to its desired signal characteristics, enabling interference-free transmission of the desired signal. Prior art two is an algebraic method of physical layer network coding. A new physical layer network coding scheme is designed through the grid partition method. This method shows that the use of codec technology can take advantage of interference in wireless networks, rather than simply Treat it as a harmful signal. The third prior art is based on the research on the throughput of the cognitive relay network based on the interference of the primary user by energy collection. The throughput of the secondary user interfered by the primary user in the cognitive relay network is analyzed. The relay is equipped with an energy collection device for energy supply, which can Assists the secondary user in transmitting information from the secondary user transmitter to the secondary user receiver in decode-and-forward mode. The above technology needs to lose part of the power of the interfering communication pair or the interfering communication pair as a cost to eliminate the influence of the interference, thus reducing the spectral efficiency of the system and further causing the system performance to be degraded.

To sum up, the problems existing in the prior art are: the existing interference management methods still regard interference as a negative factor affecting communication, ignoring that the interference may contain useful information, or the information carried by the interference can be treated by some means Possibility of converting into useful information. Therefore, in order to eliminate the negative influence of interference, the existing interference management methods always pay a corresponding price, thereby causing the performance of the communication system to be degraded.

The difficulty and significance of solving the above technical problems:

The difficulty of solving the above problems lies in how to obtain the positive factors in the interference and how to make full use of the information extracted from the interference to improve the performance of the communication system. The significance lies in that the interference will no longer have a negative impact on the desired communication, and the desired signal can be reproduced by using the information of the interference, which greatly improves the performance of the communication system.

SUMMARY OF THE INVENTION

Aiming at the problems existing in the prior art, the present invention provides an interference management method based on interference regeneration in a wireless communication system.

The present invention is implemented in the following way: an interference management method based on interference regeneration in a wireless communication system, in which the transmitters of the interference management method based on interference regeneration in the wireless communication system share channel state information and data information, and receive interference due to interference. The transmitter corresponding to the receiver constructs the interference regeneration signal according to the information; the transmitter corresponding to the interfered receiver sends the interference regeneration signal, and the interfered receiver performs matched filtering on the received mixed signal composed of the interference and the interference regeneration signal, so as to avoid the interference from the interference. The desired data is reproduced in the middle.

Further, the interference management method based on interference regeneration in the wireless communication system includes the following steps:

Step 1, the sharing of channel state information and data information is realized between the pico base station PBS and the macro base station MBS;

Step 2, the pico base station PBS utilizes the shared information to calculate the amplitude and phase of the data x _Rc carried by the interference regeneration (IRC) signal, and constructs the IRC data x _Rc ;

Step 3, the pico base station PBS uses the precoding vector p _Rc to send the IRC data, and the expected data of the macro user MUE is sent by the macro base station MBS, which causes interference at the pico user PUE, and the pico user PUE uses the filter vector f ₀ to perform matched filtering on the received signal. , using the IRC signal to reproduce the desired signal from the interference. The pico base station PBS transmits the value of the real coefficient α to the pico user PUE through a dedicated control channel, and further demodulates desired data from the reproduced desired signal.

Further, the step 1 includes:

(1) The pico user PUE and the macro user MUE respectively estimate the channel state information between themselves and the base station and feed them back to their respective associated base stations: the macro base station MBS broadcasts the pilot signal to the macro cell user MUE and the pico cell user PUE, while the pico base station PBS Broadcast the pilot signal to the picocell user PUE, the macrocell user MUE estimates the channel state information h ₁ from the macro base station MBS to the macrocell user MUE according to the pilot signal, and the picocell user PUE estimates the pilot frequency broadcasted by the macro base station MBS and the pico base station PBS The signal estimates the interference channel state information h ₁₀ of the macro base station MBS to the pico user PUE and the expected channel state information h ₀ of the pico base station PBS to the pico user PUE;

(2) The macro cell user MUE uses a low-speed and error-free feedback link to feed back the channel state information _h1 from the macro base station MBS to the macro cell user MUE to the macro base station MBS, and the pico cell user PUE selects a dedicated control channel, and the interference channel The state information h ₁₀ and the expected channel state information h ₀ are fed back to the pico base station PBS, and the macro base station MBS and the pico base station PBS share the channel state information, the expected data x ₁ of the macro base station MBS and the expectation of the pico base station PBS through mutual cooperation between the base stations data x ₀ .

Further, the second step includes:

(1) The pico base station PBS performs singular value decomposition on the channel state information h ₀ and h ₁ to obtain the precoding vector p ₁ of the signal sent by the macro base station MBS and the precoding vector p _Rc of the IRC signal sent by the pico base station PBS, and the pico user The matched filter vector f ₀ of the PUE;

(2) The pico base station PBS sets the amplitude ρ _Rc =1 of the IRC data x _Rc ;

其中，A＝Re(β)ρ₁cosθ₁-Im(β)ρ₁sinθ₁，B＝Re(β)ρ₁sinθ₁+Im(β)ρ₁cosθ₁，

Re()和Im()分别表示取复数的实部和虚部；ρ₁和θ₁分别表示宏基站MBS的发送数据x₁的幅度和相位；P_T表示微微基站PBS与宏基站MBS的发射功率；(3) From the amplitude ρ _Rc =1 of the IRC data x _Rc , obtain the real coefficient

Among them, A=Re(β)ρ ₁ cosθ ₁ -Im(β)ρ ₁ sinθ ₁ , B=Re(β)ρ ₁ sinθ ₁ +Im(β)ρ ₁ cosθ ₁ ,

Re( ) and Im( ) represent the real and imaginary parts of complex numbers, respectively; ρ ₁ and θ ₁ represent the amplitude and phase of the transmission data x ₁ of the macro base station MBS, respectively; P _T represents the transmission of the pico base station PBS and the macro base station MBS power;

其中，ρ₀和θ₀分别表示微微用户PUE的期望数据x₀的幅度和相位，可以得到IRC数据x_Rc的相位θ_Rc；(4) When α has no solution, the communication mode without interference management is adopted between the pico base station PBS and the pico user PUE; when α has a unique solution, the interference regeneration method is directly used; when α has two solutions, take α = max{|α ₊ |, |α _- |}; then substitute α into

Wherein, ρ ₀ and θ ₀ respectively represent the amplitude and phase of the expected data x ₀ of the pico user PUE, and the phase θ _Rc of the IRC data x _Rc can be obtained;

(5) According to the amplitude ρ _Rc and the phase θ _Rc of the IRC data, construct the IRC data sent by the pico base station PBS

Another object of the present invention is to provide a wireless communication system applying the interference management method based on interference regeneration in the wireless communication system.

To sum up, the advantages and positive effects of the present invention are: for downlink transmission in a hybrid cellular system in which macro cells and pico cells coexist, an IRC for interference regeneration is constructed at the pico base station PBS by using the relative representation relationship of data symbols. Using the interaction between wireless signals, the picocell user PUE can regenerate the desired signal of the PUE from the interference after filtering.

本发明将来自宏基站MBS的干扰携带的信息转化为有用信息，从而实现了干扰能量的利用，提高了微微用户PUE的频谱效率。本发明不仅适用于单期望数据流单干扰的情况，还适用于多路期望数据流单干扰、单期望数据流多路干扰，以及多路期望数据流多路干扰的更一般情况。The present invention sends the IRC signal carrying the IRC data x _Rc at the pico base station PBS, instead of sending the desired signal carrying the desired data x ₀ , the pico user PUE can regenerate the desired signal after filtering

The invention converts the information carried by the interference from the macro base station MBS into useful information, thereby realizing the utilization of the interference energy and improving the spectrum efficiency of the pico user PUE. The present invention is not only applicable to the case of single desired data stream and single interference, but also to the more general cases of multiple desired data stream single interference, single desired data stream multipath interference, and multiple desired data stream multipath interference.

Description of drawings

FIG. 1 is a flowchart of an interference management method based on interference regeneration in a wireless communication system provided by an embodiment of the present invention.

FIG. 2 is a model diagram of a hybrid cellular system used provided by an embodiment of the present invention.

FIG. 3 is a flowchart of an implementation of an interference management method based on interference regeneration in a basic wireless communication system provided by an embodiment of the present invention.

下，不同干扰管理方法的PUE频谱效率图。Fig. 4 is provided in the embodiment of the present invention in

Below, the PUE spectral efficiency plots for different interference management methods.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, but not to limit the present invention.

The present invention aims to convert the information carried by the interference into useful information, and effectively utilize the interference, thereby improving the spectrum efficiency of the picocell users.

The application principle of the present invention will be described in detail below with reference to the accompanying drawings.

As shown in FIG. 1 , the interference management method based on interference regeneration in a wireless communication system provided by an embodiment of the present invention includes the following steps:

S101: Channel state information and data information are shared between transmitters, and the transmitter corresponding to the interfered receiver constructs an interference regeneration signal according to the information;

S102: The transmitter corresponding to the interfered receiver sends an interference regeneration signal, and the interfered receiver performs matched filtering on the received mixed signal composed of the interference and the interference regeneration signal, and reproduces desired data from the interference.

The application principle of the present invention will be further described below with reference to the accompanying drawings.

和

微微基站PBS发送IRC信号至微微蜂窝用户PUE处，宏基站MBS发送到宏用户MUE的期望信号会对微微用户PUE产生干扰，微微蜂窝工作在开放接入模式。As shown in Fig. 2, the system model used in the present invention is a hybrid cellular downlink communication system composed of a single macro cell and a single pico cell. The system includes a macro base station MBS, a pico base station PBS, multiple macro cell users MUE and Multiple picocell user PUEs. Since the interference between picocells can be avoided by operators' reasonable deployment or orthogonal resource allocation, and within a macro/picocell, one resource block is only allocated to one user, based on this, we simplify the system model to contain only 1 1 MUE and 1 PUE. The number of antennas equipped with macro base station MBS, macro cell user MUE, pico base station PBS and pico cell user PUE are

and

The pico base station PBS sends an IRC signal to the pico cell user PUE, and the desired signal sent by the macro base station MBS to the macro user MUE will interfere with the pico user PUE, and the pico cell works in open access mode.

As shown in FIG. 3 , the interference management method based on interference regeneration provided by the embodiment of the present invention specifically includes the following steps:

Step 1, the sharing of channel state information and data information is realized between the pico base station PBS and the macro base station MBS, and the implementation steps are:

Step 1a, the pico user PUE and the macro user MUE respectively estimate the channel state information between themselves and the base station and feed it back to their respective associated base stations:

The macro base station MBS broadcasts the pilot signal to the macro cell user MUE and the pico cell user PUE, and the pico base station PBS broadcasts the pilot signal to the pico cell user PUE. The macro cell user MUE estimates the relationship between the macro base station MBS and the macro cell user MUE according to the pilot signal The channel state information h ₁ , the pico cell user PUE estimates the interference channel state information h ₁₀ of the macro base station MBS to the pico user PUE and the desired channel from the pico base station PBS to the pico cell user PUE according to the pilot signals broadcast by the macro base station MBS and the pico base station PBS status information h ₀ ;

Step 1b, the macro cell user MUE uses a low-speed and error-free feedback link to feed back the channel state information h ₁ from the macro base station MBS to the macro cell user MUE to the macro base station MBS, and the pico cell user PUE selects the dedicated control channel and uses the interference channel. The state information h ₁₀ and the expected channel state information h ₀ are fed back to the pico base station PBS, and the macro base station MBS and the pico base station PBS share the channel state information, the expected data x ₁ of the macro base station MBS and the expectation of the pico base station PBS through mutual cooperation between the base stations data x ₀ ;

Step 2, the pico base station PBS uses the shared information to calculate the amplitude and phase of the data x _Rc carried by the interference regeneration (IRC) signal, thereby constructing the IRC data x _Rc , and the implementation steps are:

Step 2a, the pico base station PBS performs singular value decomposition on the channel state information h ₀ and h ₁ to obtain the precoding vector p ₁ of the signal sent by the macro base station MBS and the precoding vector p _Rc of the IRC signal sent by the pico base station PBS, and the pico user The matched filter vector f ₀ of the PUE;

Step 2b, the pico base station PBS sets the amplitude ρ _Rc =1 of the IRC data x _Rc ;

其中，A＝Re(β)ρ₁cosθ₁-Im(β)ρ₁sinθ₁，B＝Re(β)ρ₁sinθ₁+Im(β)ρ₁cosθ₁，

Re()和Im()分别表示取复数的实部和虚部；ρ₁和θ₁分别表示宏基站MBS的发送数据x₁的幅度和相位；P_T表示微微基站PBS与宏基站MBS的发射功率；Step 2c, obtain the real coefficient from the amplitude ρ _Rc =1 of the IRC data x _Rc

Among them, A=Re(β)ρ ₁ cosθ ₁ -Im(β)ρ ₁ sinθ ₁ , B=Re(β)ρ ₁ sinθ ₁ +Im(β)ρ ₁ cosθ ₁ ,

Re( ) and Im( ) represent the real and imaginary parts of complex numbers, respectively; ρ ₁ and θ ₁ represent the amplitude and phase of the transmission data x ₁ of the macro base station MBS, respectively; P _T represents the transmission of the pico base station PBS and the macro base station MBS power;

其中，ρ₀和θ₀分别表示微微用户PUE的期望数据x₀的幅度和相位，可以得到IRC数据x_Rc的相位θ_Rc；Step 2d, when α has no solution, the communication mode of non-interference management is adopted between the pico base station PBS and the pico user PUE; when α has a unique solution, the interference regeneration method can be used directly; when α has two solutions, take α =max{|α ₊ |,|α _- |}; then substitute α into

Wherein, ρ ₀ and θ ₀ respectively represent the amplitude and phase of the expected data x ₀ of the pico user PUE, and the phase θ _Rc of the IRC data x _Rc can be obtained;

Step 2e, according to the amplitude ρ _Rc and the phase θ _Rc of the IRC data, construct the IRC data sent by the pico base station PBS

Step 3, the pico base station PBS uses the precoding vector p _Rc to send the IRC data, and the expected data of the macro user MUE is sent by the macro base station MBS, causing interference at the pico user PUE, and the pico user PUE uses the filter vector f ₀ to perform matched filtering on the received signal. , using the IRC signal to reproduce the desired signal from the interference. The pico base station PBS transmits the value of the real coefficient α to the pico user PUE through a dedicated control channel, and further demodulates desired data from the reproduced desired signal.

The application effect of the present invention will be described in detail below with reference to the accompanying drawings.

1. Simulation conditions:

Simulation object: The interference management algorithm (IRC) based on interference regeneration proposed in this paper is compared with point-to-point MIMO communication (P2P MIMO) and interference steering (IS). Among them, P2P MIMO is the communication between the pico base station PBS and the pico user PUE without interference; the interference steering (IS) uses the steering signal to steer the interference observed by the pico user PUE to the direction orthogonal to its expected signal characteristics, Interference-free communication of pico-communication pairs is achieved.

的取值范围为[-10,20]dB，

为噪声功率。

其中，

和

分别是宏基站MBS的发射和接收天线数，

和

分别是微微基站PBS的发射和接收天线数。Simulation parameters: The pico base station PBS and the macro base station MBS of the hybrid cellular system use the same power PT to send single-channel data respectively, and the signal _- to-noise ratio

The value range is [-10,20]dB,

is the noise power.

in,

and

are the number of transmit and receive antennas of the macro base station MBS, respectively,

and

are the number of transmit and receive antennas of the pico base station PBS, respectively.

2. Simulation content and analysis:

时，对微微蜂窝用户PUE的频谱效率进行仿真，其结果如图4所示，其中，纵轴表示频谱效率，横轴表示信噪比，由于IRC有效地利用了干扰的能量，将干扰转化为期望信号，其获得的频谱效率优于P2P MIMO。干扰导向(IS)是在受干扰接收机对应的发射机处进行实施，产生导向信号的功率开销导致IS的频谱效率低于P2P MIMO和IRC方法。when

When , the spectral efficiency of the picocell user PUE is simulated, and the results are shown in Figure 4, where the vertical axis represents the spectral efficiency, and the horizontal axis represents the signal-to-noise ratio. Since the IRC effectively utilizes the energy of the interference, the interference is converted into desired signal, which achieves better spectral efficiency than P2P MIMO. Interference Steering (IS) is implemented at the transmitter corresponding to the interfered receiver, and the power overhead of generating the steering signal results in the spectral efficiency of IS being lower than that of P2P MIMO and IRC methods.

The above descriptions are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention shall be included in the protection of the present invention. within the range.

Claims (2)

1. an interference management method based on interference regeneration in a wireless communication system, characterized in that, channel state information and data information are shared between transmitters, and the transmitter corresponding to the interfered receiver constructs an interference regeneration signal according to the information; The transmitter corresponding to the receiver sends the interference regeneration signal, and the interfered receiver performs matched filtering on the received mixed signal composed of the interference and the interference regeneration signal, and reproduces the desired data from the interference; The interference management method based on interference regeneration includes the following steps: Step 1, the sharing of channel state information and data information is realized between the pico base station PBS and the macro base station MBS; Step 2, the pico base station PBS utilizes the shared information to calculate the amplitude and phase of the data x _Rc carried by the interference regeneration (IRC) signal, and constructs the IRC data x _Rc ; Step 3, the pico base station PBS uses the precoding vector p _Rc to send the IRC data, and the expected data of the macro user MUE is sent by the macro base station MBS, which causes interference at the pico user PUE, and the pico user PUE uses the filter vector f ₀ to perform matched filtering on the received signal. , using the IRC signal to regenerate the desired signal from the interference; the pico base station PBS transmits the value of the real coefficient α to the pico user PUE through the dedicated control channel, and then demodulates the desired data from the regenerated desired signal; The first step includes: (1) The pico user PUE and the macro user MUE respectively estimate the channel state information between themselves and the base station and feed them back to their respective associated base stations: the macro base station MBS broadcasts the pilot signal to the macro cell user MUE and the pico cell user PUE, while the pico base station PBS Broadcast the pilot signal to the picocell user PUE, the macrocell user MUE estimates the channel state information h ₁ from the macro base station MBS to the macrocell user MUE according to the pilot signal, and the picocell user PUE estimates the pilot frequency broadcasted by the macro base station MBS and the pico base station PBS The signal estimates the interference channel state information h ₁₀ of the macro base station MBS to the pico user PUE and the expected channel state information h ₀ of the pico base station PBS to the pico user PUE; (2) The macro cell user MUE uses a low-speed and error-free feedback link to feed back the channel state information _h1 from the macro base station MBS to the macro cell user MUE to the macro base station MBS, and the pico cell user PUE selects a dedicated control channel, and the interference channel The state information h ₁₀ and the expected channel state information h ₀ are fed back to the pico base station PBS, and the macro base station MBS and the pico base station PBS share the channel state information, the expected data x ₁ of the macro base station MBS and the expectation of the pico base station PBS through mutual cooperation between the base stations data x ₀ ; The second step includes: (1) The pico base station PBS performs singular value decomposition on the channel state information h ₀ and h ₁ to obtain the precoding vector p ₁ of the signal sent by the macro base station MBS and the precoding vector p _Rc of the IRC signal sent by the pico base station PBS, and the pico user The matched filter vector f ₀ of the PUE; (2) The pico base station PBS sets the amplitude ρ _Rc =1 of the IRC data x _Rc ; (3) From the amplitude ρ _Rc =1 of the IRC data x _Rc , obtain the real coefficient

Among them, A=Re(β)ρ ₁ cosθ ₁ -Im(β)ρ ₁ sinθ ₁ , B=Re(β)ρ ₁ sinθ ₁ +Im(β)ρ ₁ cosθ ₁ ,

Re( ) and Im( ) represent the real and imaginary parts of complex numbers, respectively; ρ ₁ and θ ₁ represent the amplitude and phase of the transmission data x ₁ of the macro base station MBS, respectively; P _T represents the transmission of the pico base station PBS and the macro base station MBS power; (4) When α has no solution, the communication mode without interference management is adopted between the pico base station PBS and the pico user PUE; when α has a unique solution, the interference regeneration method is directly used; when α has two solutions, take α = max{|α ₊ |, |α _- |}; then substitute α into

Wherein, ρ ₀ and θ ₀ respectively represent the amplitude and phase of the expected data x ₀ of the pico user PUE, and the phase θ _Rc of the IRC data x _Rc can be obtained; (5) According to the amplitude ρ _Rc and the phase θ _Rc of the IRC data, construct the IRC data sent by the pico base station PBS

2. A wireless communication system to which the interference management method based on interference regeneration in the wireless communication system of claim 1 is applied.

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