CN102158891B - Method for receiving and detecting network coding - Google Patents

Abstract

The invention discloses a method for receiving and detecting network coding, which is applied in a two-way relay system. The method includes: user equipment estimates the channel fading information of the link between itself and the relay station according to the pilot information sent by the relay station; The relay station sends the information sent by the user, and the relay station amplifies and forwards the received network coding information; after receiving the forwarded network coding information, the user equipment uses the estimated channel fading information to suppress the interference caused by the user sending information sent by itself; then uses its own channel fading The estimated value of the information and the statistical characteristics of channel fading from the opposite end user equipment to the relay station are detected to obtain the user transmission information sent by the opposite end user equipment. The invention solves the problem that the reception and detection cannot be performed due to the inability to obtain the global real-time channel state information in the wireless network coding communication, simplifies the design of the network coding transmission system, and improves the spectral efficiency of transmission.

Description

A Reception Detection Method of Network Coding

technical field

The invention relates to wireless transmission technology in the field of communication technology, in particular to a method for receiving and detecting network coding.

Background technique

In order to make full use of limited wireless resources, expand network coverage and improve system throughput, wireless relay technology is introduced into the next generation mobile communication system. However, the relay transmission will reduce the spectral efficiency of the system, thereby causing the overall performance of the network to decline. The proposal of network coding provides a feasible solution to improve the spectral efficiency of wireless networks, so the proposal of using network coding technology in the next generation mobile communication system has been widely supported. Among them, physical layer network coding has attracted extensive attention as a simple and efficient transmission method.

Physical layer network coding is suitable for two-way relay transmission scenarios, and the schematic diagram of the corresponding transmission principle is shown in Figure 1. In this transmission scenario, user equipment 1 and user equipment 2 belonging to the same user pair need to transmit information through a relay station, and there is no direct link between user equipment 1 and user equipment 2 . The physical layer network coding transmission method is adopted, which is divided into two stages, and each stage occupies a time slot for transmission. In the first stage, the two user equipments send the user transmission information to the relay station at the same time, and the relay station receives the network coding information of the user transmission information sent by the two user equipments; in the second stage, the relay station transmits the network coding information to the two The user equipment performs amplification and forwarding, and the two user equipments restrain their own transmission information from the received network coding information, and obtain the user transmission information of the other user equipment in the user pair to which they belong. In the traditional relay forwarding method, user equipment 1 and user equipment 2 need to occupy different time slots for information transmission and relay forwarding, so the traditional relay forwarding method requires 4 time slots, and the spectrum efficiency is low. However, the transmission method using physical layer network coding only needs 2 time slots. Therefore, compared with the traditional relay forwarding method, the use of physical layer network coding can reduce the transmission delay by 50%, and can double the spectrum efficiency.

However, in practical applications, the physical layer network coding has problems when the user equipment performs reception detection on the received network coding information. Taking the scenario shown in Figure 1 as an example, if user equipment 1 wants to obtain the network coding information sent by user equipment 2 belonging to the same user pair from the received network coding information, it needs to obtain the network coding information sent by user equipment 1 and user equipment 2 to the relay at the same time. The real-time channel state information of the link is accurate, but the actual system can only ensure that the user equipment obtains the real-time channel state information from itself to the relay station, and due to the time-varying nature of the channel, it cannot guarantee the accuracy of the channel state information, nor can it guarantee that the user equipment can obtain the real-time channel state information of the relay station. The real-time channel state information from the user equipment to the relay station makes it impossible for the user equipment to obtain the required information from the network coding information, resulting in the inability to realize the physical layer network coding.

Contents of the invention

An embodiment of the present invention provides a network coding reception detection method, so as to realize the reception detection of the physical layer network coding transmission method.

The network coding reception detection method provided by the embodiment of the present invention is applied to a two-way relay system, and is characterized in that the first user equipment and the second user equipment in the user pair receive the pilot information sent by the relay station, and according to the received pilot information Obtain the estimated value of the channel fading information from itself to the relay station through the frequency information; the method includes:

The first user equipment and the second user equipment simultaneously send the information sent by the user to the relay station, and the relay station receives the network coding information of the information sent by the two users;

After receiving the network coding information of the information sent by the users of the first user equipment and the second user equipment, the relay station amplifies and forwards the network coding information to the first user equipment and the second user equipment;

After the first and second user equipments receive the network coding information forwarded by the relay station, they suppress the interference caused by the user transmission information sent by themselves according to the estimated value of the channel fading information from themselves to the relay station, and obtain the processed network coding information; according to their own The estimated value of the channel fading information to the relay station and the statistical characteristics of the channel fading from the peer end user equipment to the relay station are detected from the processed network coding information to detect the user transmission information sent by the peer end user equipment;

Wherein, the user equipment obtains the channel fading statistical characteristics from the opposite end user equipment to the relay station through preset settings during system initialization.

In the above method, the user equipment uses the following formula to calculate the estimated value of channel fading information from itself to the relay station:

为用户设备自身到中继站的信道衰落信息的估计值，

为用户设备接收的导频信息；

为中继站发送的导频信息，为发送导频信息的发送功率，所述中继站在同一个时隙向所述第一用户设备和第二用户设备发送导频信息。 in,

is the estimated value of the channel fading information from the user equipment itself to the relay station,

pilot information received by the user equipment;

is the pilot information sent by the relay station, To send pilot information , the relay station sends pilot information to the first user equipment and the second user equipment in the same time slot.

In the above method, the user equipment suppresses the interference caused by the user transmission information sent by itself according to the estimated value of the channel fading information from itself to the relay station, and the processed network coding information is obtained as:

为所述用户设备处理后的网络编码信息，

为所述用户设备接收的中继站转发的网络编码信息，为中继站转发网络编码信息的发送功率，

为用户设备发送的用户发送信息，

为用户设备发送所述用户发送信息的发送功率，

为用户设备自身到中继站的信道衰落信息的估计值。 in,

encoding the processed network information for the user equipment,

the network coding information forwarded by the relay station received by the user equipment, transmit power for the relay station to forward network coded information,

User sent information sent by user equipment,

sending the transmit power of the user transmit information for the user equipment,

is the estimated value of the channel fading information from the user equipment itself to the relay station.

In the above method, the user equipment detects the user transmission information sent by the opposite end user equipment from the processed network coding information according to the estimated value of the channel fading information from itself to the relay station and the statistical characteristics of the channel fading from the opposite end user equipment to the relay station, Specifically:

According to the possible values in the set of constellation point values corresponding to the modulation mode adopted by the peer user equipment, the estimated value of the channel fading information from the user equipment to the relay station, and the statistical characteristics of the channel fading from the peer user equipment to the relay station, the user equipment obtains The decision parameter corresponding to the value:

为中继发送网络编码信息的发送功率，

为用户设备发送用户发送信息的发送功率，

为用户设备到中继站的信道衰落信息的估计值的共轭转置，

是中继站接收的网络编码信息的功率归一化因子，

为对端用户设备到中继站的信道衰落信息的方差，

为第一用户设备接收网络编码信息时的噪声的方差，

是中继站接收网络编码信息时的噪声的方差，

为对端用户设备发送用户发送信息时采用的调制方式对应星座图点集合中的一个取值，

为对应的判决参数； in,

transmit power for relaying network coded information,

transmit power for the user equipment to transmit the information transmitted by the user,

is the conjugate transpose of the estimated value of the channel fading information from the user equipment to the relay station,

is the power normalization factor of the network coded information received by the relay station,

is the variance of the channel fading information from the end user equipment to the relay station,

is the variance of the noise when the first user equipment receives the network coding information,

is the variance of the noise when the relay station receives the network coded information,

The modulation method used when sending information to the peer user equipment corresponds to a value in the constellation diagram point set,

for Corresponding decision parameters;

The user equipment calculates the corresponding posterior probability under the Rayleigh channel condition according to the decision parameter corresponding to the value:

The user equipment makes a judgment according to the posterior probability obtained by the judgment parameter corresponding to the value, and obtains the detected value of the user sent information sent by the opposite end user equipment:

进行检测得到的对端用户设备发送的用户发送信息的检测值，

为对端用户设备发送用户发送信息时采用的调制方式对应星座图点取值的集合。 in, for user equipment

The detection value of the user-sent information sent by the peer user equipment obtained through detection,

A set of constellation diagram point values corresponding to the modulation mode adopted when the peer user equipment sends the user transmission information.

Compared with the prior art, the present invention has at least the following advantages:

The user equipment estimates the channel fading information from the user equipment itself to the relay station by receiving the pilot information sent by the relay station. The user equipment and the peer user equipment belonging to the same user pair as the user equipment simultaneously send user transmission information to the relay station. The network coding information of the information sent by the user is amplified and forwarded to the two user equipments in the user pair. The user equipment receives the network coding information and suppresses the interference caused by the user sending information sent by itself. According to the estimated distance from itself to the relay station The channel fading information, and the statistical characteristics of channel fading from the opposite end user equipment to the relay station, the user equipment can detect the user transmission information sent by the opposite end user equipment from the network coding information after interference suppression. The technical scheme of the invention solves the problem that network coding reception and detection cannot be performed due to the inability to obtain global real-time channel state information in wireless communication, simplifies the design of the network coding transmission system, and improves the spectral efficiency of transmission.

Description of drawings

FIG. 1 is a schematic diagram of the physical layer network coding transmission principle in the prior art;

FIG. 2 is a schematic diagram of a network coding reception detection process provided by an embodiment of the present invention;

FIG. 3 is a schematic diagram of a design of a network coding reception detection system provided by an embodiment of the present invention;

FIG. 4 is a schematic structural diagram of a transmission frame provided by an embodiment of the present invention.

Detailed ways

The wireless network coding transmission method represented by the physical layer network coding will encounter the above-mentioned problems when the user performs reception detection. Aiming at the reception detection problem of wireless network coding information, the present invention proposes a reception detection algorithm of network coding information. Specifically, the user equipment uses the pilot information sent by the relay station to estimate the channel fading information from itself to the relay station, and then according to the user transmission information sent by itself, the estimated channel fading information is obtained from the received network coding information sent by the relay station Suppress the interference caused by the user-sent information sent by itself, and use the channel fading information estimated by itself and the channel fading statistical characteristics from the peer user equipment to the relay station to detect the network coding information after interference suppression, and obtain the other user in the user pair User-sent information sent by the device. This method solves the problem that the wireless network coding cannot obtain the global real-time channel state information, which leads to the inability to perform reception detection, and at the same time simplifies the design of the network coding transmission system, and improves the spectral efficiency of transmission.

The following will clearly and completely describe the technical solution of the present invention in conjunction with the accompanying drawings of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

As shown in FIG. 2 , an embodiment of the present invention provides a network coding reception detection method, which is applied to a two-way relay system. Scenarios to which the method is applicable include but are not limited to: a wireless communication system including a two-way relay station and two user equipments belonging to the same user pair. Due to the symmetry of the network topology, without loss of generality, the following takes the processing process of the first user equipment as an example for illustration. The method includes the following steps:

Step 201, the relay station sends pilot information to the first user equipment and the second user equipment, and the first user equipment and the second user equipment estimate channel fading information from themselves to the relay station according to the received pilot information.

Preferably, the relay station sends pilot information to the first user equipment and the second user equipment in the same time slot.

Take the first user equipment to estimate the channel fading information from itself to the relay station according to the pilot information received by the relay station as an example: the pilot information received by the first user equipment is transmitted by the relay station to transmit the pilot information, the first user equipment to The channel fading information of the relay station and the noise when the first user equipment receives the pilot information are determined. The pilot information received by the first user equipment is expressed as:

为中继站发送的导频信息，

为导频信息

的发送功率，是第一用户设备到中继站的信道衰落信息，

为第一用户设备接收导频信息时的噪声。 in,

is the pilot information sent by the relay station,

for pilot information

the transmit power, is the channel fading information from the first user equipment to the relay station,

is the noise when the first user equipment receives the pilot information.

在第一用户设备处已知，如可以在系统初始化的时候对中继站和第一用户设备进行相应的设定，使得第一用户设备获知中继站发送的导频信息

。第一用户设备接收导频信息时的噪声为随机值。 in,

It is known at the first user equipment that, for example, the relay station and the first user equipment can be configured correspondingly during system initialization, so that the first user equipment knows the pilot information sent by the relay station

. The noise when the first user equipment receives the pilot information is a random value.

和

的关系可以得知，第一用户设备可根据接收导频信息时的噪声、中继站发送的导频信息的发送功率和中继站发送的导频信息，计算得到第一用户设备自身到中继站的信道衰落信息的估计值。在本实施例中，以迫零检测方法为例，第一用户设备自身到中继站的信道衰落信息估计值

为： from

and

It can be known that the first user equipment can calculate the channel fading information from the first user equipment itself to the relay station according to the noise when receiving the pilot information, the transmission power of the pilot information sent by the relay station, and the pilot information sent by the relay station estimated value. In this embodiment, taking the zero-forcing detection method as an example, the estimated channel fading information from the first user equipment itself to the relay station is

for:

In addition to the zero-forcing detection method, the first user equipment may also use other detection methods, such as a minimum mean square error detection method to estimate channel fading information from itself to the relay station.

Step 202, the first user equipment and the second user equipment simultaneously send the user transmission information to the relay station, the relay station receives the network coding information of the two user transmission information, amplifies and forwards the network coding information, and sends it to the first user equipment and the second user equipment. The user equipment, the first user equipment and the second user equipment receive the network coding information forwarded by the relay station.

The network coding information received by the relay station can be expressed as:

为第一用户设备发送的用户发送信息，为第二用户设备发送的用户发送信息，

为第一用户设备发送的发送功率，第二用户设备的发送功率和第一用户设备相同，

为第一用户设备到中继站的信道衰落信息，

为第二用户设备到中继站的信道衰落信息，

为中继站接收网络编码信息时的噪声。 in,

sending information for the user sent by the first user equipment, sending information for the user sent by the second user equipment,

sent for the first user equipment The transmit power of the second user equipment is the same as that of the first user equipment,

is the channel fading information from the first user equipment to the relay station,

is the channel fading information from the second user equipment to the relay station,

Noise when receiving network-encoded information for relay stations.

The relay station amplifies and forwards the network coding information Can be expressed as:

为中继发送网络编码信息的发送功率，

是中继站接收的网络编码信息的功率归一化因子，且

，

、

分别为第一用户设备和第二用户设备到中继站的信道衰落信息

、

的方差，

是中继站接收网络编码信息时的噪声

的方差。因为信道衰落信息

、

为随机变量，为了保证中继站的功率恒定，中继站对转发信息进行归一化处理。 in,

transmit power for relaying network coded information,

is the power normalization factor of the network coded information received by the relay station, and

,

,

are the channel fading information from the first user equipment and the second user equipment to the relay station respectively

,

Variance,

is the noise when the relay station receives the network coded information

Variance. because of channel fading information

,

is a random variable, and in order to ensure a constant power of the relay station, the relay station performs normalization processing on the forwarding information.

The network coding information received by the first user equipment may be expressed as:

为第一用户设备接收网络编码信息时的噪声。 in,

Noise when receiving network coded information for the first UE.

Step 203, the first user equipment suppresses the interference caused by the user transmission information sent by itself from the received network coding information according to the estimated value of the channel fading information from itself to the relay station, and obtains the processed network coding information.

In the network coding information received by the first user equipment, the interference caused by the user transmission information sent by itself may be based on the power normalization factor of the network coding information received by the relay station, the user transmission information sent by the first user equipment, the first user equipment The transmitted transmission power of the transmitted information of the user, the transmitted power of the network coding information transmitted by the relay station, and the estimated value of channel fading information from the first user equipment itself to the relay station are calculated.

为： The network coding information after the first user equipment suppresses the interference caused by the user transmission information sent by itself from the received network coding information

for:

Step 204, the first user equipment corresponds to each possible value in the set of constellation point values, the estimated value of channel fading information from the first user equipment to the relay station, and the channel fading information from the second user equipment to the relay station according to the modulation method adopted by the second user equipment. Statistical characteristics of the channel fading, to obtain the decision parameters corresponding to each value.

The statistical characteristics of channel fading from the second user equipment to the relay station can be obtained through pre-setting when the system is initialized before the transmission starts. The decision parameters can be expressed as:

为第二用户设备发送用户发送信息采用的调制方式对应星座图点集合中的一个取值，

为

对应的判决参数。 in,

The modulation mode used for sending the user sending information for the second user equipment corresponds to a value in the constellation diagram point set,

for

Corresponding decision parameters.

Step 205, the first user equipment obtains the corresponding a posteriori probability according to the decision parameters corresponding to each possible value in the set of constellation point values corresponding to the modulation mode adopted by the second user equipment.

和

已知的条件下，网络编码信息对应的后验概率为，在瑞利信道条件下，

可以按如下表达式得到：

and

Under known conditions, the network encodes information The corresponding posterior probability is , under the Rayleigh channel condition,

It can be obtained by the following expression:

Step 206: The first user equipment makes a judgment according to the posterior probability corresponding to each possible value in the set of constellation point values corresponding to the modulation mode adopted by the second user equipment, and obtains the detection of the user transmission information sent by the second user equipment. value.

Specifically, taking the maximum likelihood detection method as an example, the detection value of the user transmission information sent by the second user equipment detected by the first user equipment is:

为第一用户设备对

进行检测得到的第二用户设备发送的用户发送信息检测值，

为第二用户设备发送用户发送信息时采用的调制方式对应星座图点取值的集合。 in,

For the first user equipment pair

The detection value of the user transmission information sent by the second user equipment obtained through detection,

The modulation mode adopted when sending the user transmission information for the second user equipment corresponds to a set of constellation diagram point values.

的检测值

： Obtain the information sent by the user sent by the second user equipment

detection value of

:

，得到自身到中继站的信道衰落信息的估计值

，之后第一用户设备根据自身到中继站的信道衰落信息的估计值，从接收的网络编码信息中抑制自身发送的用户发送信息造成的干扰，得到处理后的网络编码信息

。第一用户设备计算第二用户设备采用的调制方式对应星座图点取值的集合中的取值

对应的判决参数

，并根据上述公式进一步得到各个取值对应的后验概率，从而得到第二用户设备发送的用户发送信息的检测值

。 Figure 3 is a schematic diagram of the user transmission information detection system, the first user equipment according to the pilot information sent by the relay station

, get the estimated value of the channel fading information from itself to the relay station

, then the first user equipment suppresses the interference caused by the user transmission information sent by itself from the received network coding information according to the estimated value of the channel fading information from itself to the relay station, and obtains the processed network coding information

. The first user equipment calculates a value in a set of constellation point values corresponding to the modulation mode adopted by the second user equipment.

Corresponding decision parameters

, and further obtain the posterior probability corresponding to each value according to the above formula, so as to obtain the user sent information sent by the second user equipment detection value of

.

After receiving the network coding information forwarded by the relay station, the second user equipment detects the user sending information of the first user equipment from the received network coding information in the same manner as the first user equipment.

In the above embodiments of the present invention, by using the statistical characteristics of channel fading from the peer-end user equipment to the relay station, the information sent by the user of the peer-end user equipment can be detected by using the maximum likelihood detection method, which overcomes the transmission delay of the physical layer network coding , the problem of not being able to detect received network coding information due to unavailability of global instant channel state information. In this embodiment, the maximum likelihood detection method is taken as an example, which is an ideal detection algorithm, and other detection methods may also be used in practical applications. In this embodiment, the approximate expression of the posterior probability is obtained under the Rayleigh channel condition. In practical applications, other channel approximations may also be used for detection.

To sum up, adopting the technical solution provided by the embodiment of the present invention can at least have the following advantages: the first user equipment can estimate and obtain the channel fading information from the first user equipment itself to the relay station by receiving the pilot information sent by the relay station. The user equipment and the second user equipment belonging to the same user pair as the first user equipment simultaneously send the user transmission information to the relay station, and the relay station amplifies and forwards the information to the first user equipment and the second user equipment according to the received network coding information, and the first user equipment The device receives the network coding information sent by the relay station, and suppresses the interference caused by the user sending information sent by itself from the network coding information, according to the estimated value of the channel fading information from itself to the relay station, and the channel fading statistical characteristics of the second user equipment to the relay station , the first user equipment can detect the user transmission information sent by the second user equipment from the network coding information after interference suppression, which solves the problem that the network coding information cannot be received and detected due to the inability to obtain global real-time channel state information in wireless communication The problem simplifies the design of the network coding transmission system and improves the spectral efficiency of transmission.

In order to illustrate the technology of the embodiment of the present invention more clearly, the embodiment of the present invention provides a schematic diagram of a transmission frame structure applied to the above process, as shown in FIG. 4 .

In a scenario where the user equipment is stationary or moves at a low speed, the channel fading information from the user equipment to the relay station changes slowly. Therefore, under the condition that the detection error rate of the user equipment is allowed, the pilot information sent by the relay station can be used to estimate the channel fading information from itself to the relay station once, and then perform multiple user transmissions between user pairs, and adopt the above The method for detecting the reception of network coding information in the embodiment performs detection.

个时隙，

（

为自然数）。在第1个时隙中，中继站向用户设备1和用户设备2发送导频信息，两用户设备分别对自身到中继站的信道衰落信息进行估计。在随后的2M个时隙中，用户设备1和用户设备2采用网络编码，进行M次用户发送信息的传输。如图4所示，在一次网络编码信息的传输的两个时隙中，在第一个时隙，所述两个用户设备1和用户设备2分别向所述中继站发送用户发送信息；在第二个时隙，中继站将两个用户设备发送的网络编码信息放大转发给两个用户。 Specifically, as shown in Figure 4, for wireless network coded transmission, when using the network coded information reception detection method in the embodiment of the present invention, a frame includes

slots,

(

is a natural number). In the first time slot, the relay station sends pilot information to user equipment 1 and user equipment 2, and the two user equipments respectively estimate channel fading information from themselves to the relay station. In the following 2M time slots, user equipment 1 and user equipment 2 use network coding to transmit information sent by users M times. As shown in FIG. 4, in two time slots of a transmission of network coding information, in the first time slot, the two user equipment 1 and user equipment 2 respectively send user transmission information to the relay station; In two time slots, the relay station amplifies and forwards the network coding information sent by the two user equipments to the two users.

The value of M is jointly determined by the change speed of channel fading information and the tolerance to the transmission error rate. When the channel fading information changes more slowly, and the tolerance to the transmission error rate is higher, the value of M is larger, and the channel fading information can be estimated once, and more user pairs can transmit information sent by users .

Through the transmission frame structure provided by this embodiment, when the channel state is ideal, in the first time slot of a frame, the relay station sends pilot information to two user equipments belonging to the same user pair, and the two user equipments The user estimates the channel fading information from itself to the relay station respectively, and transmits the network coding information in other time slots of the frame, which improves the transmission performance of the network coding and obtains higher spectrum efficiency.

Through the description of the above embodiments, those skilled in the art can clearly understand that the present invention can be implemented by means of software plus a necessary general-purpose hardware platform, and of course also by hardware, but in many cases the former is a better implementation Way. Based on this understanding, the essence of the technical solution of the present invention or the part that contributes to the prior art can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions to make a A computer device (which may be a personal computer, a server, or a network device, etc.) executes the methods described in various embodiments of the present invention.

Those skilled in the art can understand that the drawing is only a schematic diagram of a preferred embodiment, and the modules or processes in the drawing are not necessarily necessary for implementing the present invention.

The serial numbers of the above embodiments of the present invention are for description only, and do not represent the advantages and disadvantages of the embodiments.

The above disclosures are only a few specific embodiments of the present invention, however, the present invention is not limited thereto, and any changes conceivable by those skilled in the art shall fall within the protection scope of the present invention.

Claims (3)

1. A receiving detection method of network coding is applied to a bidirectional relay system and is characterized in that a first user device and a second user device in a user pair receive pilot frequency information sent by a relay station and obtain an estimation value of channel fading information from the first user device to the relay station according to the received pilot frequency information; the method comprises the following steps:

the first user equipment and the second user equipment simultaneously send user sending information to the relay station, and the relay station receives network coding information of the two user sending information;

after receiving network coding information of information sent by users of first user equipment and second user equipment, the relay station amplifies and forwards the network coding information to the first user equipment and the second user equipment;

after the first user equipment and the second user equipment receive the network coding information forwarded by the relay station, the interference caused by user sending information sent by the first user equipment is restrained according to the estimated value of the channel fading information from the first user equipment to the relay station, and the processed network coding information is obtained; detecting user sending information sent by opposite-end user equipment from the processed network coding information according to an estimated value of channel fading information from the user equipment to the relay station and channel fading statistical characteristics from the opposite-end user equipment to the relay station;

the user equipment obtains the channel fading statistical characteristics from the opposite-end user equipment to the relay station through presetting when a system is initialized;

the user equipment calculates an estimated value of channel fading information from the user equipment to the relay station by adopting the following formula:

${\hat{h}}_1=r_{P1}{\left(\sqrt{E_T}{s}_P\right)}^{-1}$

wherein,

is an estimated value of channel fading information from the user equipment itself to the relay station, r_P1Pilot information received for the user equipment; s_PPilot information transmitted for relay stations, E_TFor transmitting pilot information s_PThe relay station transmits pilot information to the first user equipment and the second user equipment in the same time slot.

2. The method of claim 1, wherein the ue suppresses interference caused by the ue transmission information transmitted by the ue according to the estimated value of the channel fading information from the ue to the relay station, and the obtained processed network coding information is:

$y_1=r_1-A\sqrt{E_s}\sqrt{E_R}{\hat{h}}_1^H{\hat{h}}_1{s}_1$

wherein, y₁Encoding information for said user equipment processed network, r₁Network coding information forwarded by the relay station received by said user equipment, E_RTransmitting power, s, for relaying network coded information for a relay station₁For transmitting information to the user equipment, E_sA transmit power at which the user transmit information is transmitted for a user equipment,

is an estimation value of the channel fading information from the user equipment to the relay station, A is a power normalization factor of the network coding information received by the relay station,

is the conjugate transpose of the estimated value of the channel fading information from the user equipment itself to the relay station.

3. The method of claim 1, wherein the ue detects the user transmission information sent by the peer ue from the processed network coding information according to an estimated value of channel fading information from the ue to the relay station and statistical characteristics of channel fading from the peer ue to the relay station, specifically:

the user equipment obtains a decision parameter corresponding to a modulation mode adopted by the opposite-end user equipment according to possible values in a set of constellation point values corresponding to the modulation mode, estimated values of channel fading information from the user equipment to a relay station and statistical characteristics of channel fading from the opposite-end user equipment to the relay station:

${\mathrm{\η}}_i=A^2{E}_R{\left|{\hat{h}}_1^H\right|}^2(E_s{\left|{\tilde{s}}_2\left(i\right)\right|}^2{\mathrm{\σ}}_2^2+N_R)+N_1$

wherein E is_RTransmission power for relaying network-coded information, E_sTransmit power for the user equipment to transmit user transmit information,

which is the conjugate transpose of the estimated value of the channel fading information from the user equipment to the relay station, a is the power normalization factor of the network coding information received by the relay station,

variance of channel fading information for peer user equipment to relay station, N₁Variance of noise when receiving network coded information for a first user equipment, N_RIs the variance of the noise when the relay station receives the network coded information,a modulation mode adopted when the opposite-end user equipment sends the user sending information corresponds to a value, eta, in the constellation map point set_iIs composed of

Corresponding decision parameters;

and the user equipment calculates the corresponding posterior probability under the Rayleigh channel condition according to the judgment parameter corresponding to the value:

$p\left(y_1\right|s_1,{\tilde{s}}_2\left(i\right))=\frac{1}{\sqrt{2\mathrm{\π}{\mathrm{\η}}_i}}\exp \{-\frac{{\left|y_1\right|}^2}{2{\mathrm{\η}}_i}\}$

wherein S is₁For transmitting information to the user transmitted by the first user equipment, y₁Encoding information for the network processed by the user equipment;

the user equipment judges according to the posterior probability obtained by the judgment parameter corresponding to the value, and obtains the detection value of the user sending information sent by the opposite end user equipment:

${\hat{s}}_2=\arg \underset{{\tilde{s}}_2\left(i\right)\∈M_s}{\max }p\left(y_1\right|s_1,{\tilde{s}}_2\left(i\right))$

wherein,

for the user equipment pair y₁Detecting the detected value of the user sending information sent by the opposite end user equipment, M_sAnd a modulation mode adopted when the opposite-end user equipment sends the user sending information corresponds to the set of the values of the constellation map points.

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