WO2014206253A1

WO2014206253A1 - Method and device for transmission scheduling in cognitive radio system

Info

Publication number: WO2014206253A1
Application number: PCT/CN2014/080485
Authority: WO
Inventors: 李媛媛; 蒋成钢; 白文岭; 杨宇; 胡金玲
Original assignee: 电信科学技术研究院
Priority date: 2013-06-24
Filing date: 2014-06-23
Publication date: 2014-12-31
Also published as: CN104243056B; CN104243056A

Abstract

Embodiments of the present application relate to the field of radio communications. Disclosed are a method and device for spectrum sensing in a cognitive radio (CR) system, for use in increasing the performance of the CR system. In the present application, a central management device determines multiple sensing nodes capable of sensing a target frequency and geolocation information of an authorization system corresponding to the target frequency, divides the multiple sensing nodes into multiple cooperative sensing clusters, assigns a sensing task to each cooperative sensing cluster, where the sensing task comprises time information for spectrum sensing with respect to the target frequency, and notifies the sensing nodes in the corresponding cooperative sensing cluster of the sensing task assigned to each cooperative cluster, and, the sensing nodes sense a spectrum with respect to the target frequency on the basis of the sensing task as notified. Employment of the present solution allows for increased performance of the CR system.

Description

Transmission scheduling method and apparatus in cognitive radio system This application claims to be filed on June 24, 2013 by the Chinese Patent Office, application number 201310253098.7, and the Chinese patent entitled "Transmission Scheduling Method and Apparatus in Cognitive Radio System" Priority of the application, the entire contents of which are incorporated herein by reference. Technical field

The present application relates to the field of wireless communications, and in particular, to a spectrum sensing method and apparatus in a cognitive radio system. Background technique

Radio communication frequency is a valuable natural resource. With the rapid development of wireless communication technology, the problem of poor spectrum resources is becoming more and more serious. In order to alleviate the current situation of spectrum resources, relevant departments and agencies have monitored the wireless communication spectrum. Studies have found that certain frequency bands (such as TV bands) have not been used most of the time or have not been used in most areas, and some bands have experienced multi-system and multi-user simultaneous competition, namely spectrum resources. There is an imbalance in the use. The concept of CR (Cognitive Radio) is generated in this context. The basic idea is: Under the premise of not causing interference to the authorization system, the cognitive radio system can monitor the changes in the current wireless environment. Dynamically opportunistic access to white space for communication.

The application scenarios of cognitive radio are mainly divided into two categories. The first category is the spectrum of the opportunistic use authorization system. For example, the IMT (International Mobile Telecommunications) system uses the blank frequency of the broadcast television system; the second category is Multiple sensing systems opportunistically use a frequency band that is not affiliated with any system. The multiple systems use a certain frequency band fairly, that is, when a certain frequency point is idle, it can be used, or it can be used according to a certain priority. (Unfair) A certain frequency band, that is, when a system with a higher priority uses a certain frequency point, the system with a lower priority level will withdraw from the use of the corresponding frequency point.

For the first type of scenario, and the second type of unfair use scenario, to ensure the service performance of the authorization system or the high priority system, it is required to:

The sensing system accurately determines which frequency bands are available white space bands (the introduction of a sensing system in these frequency bands does not affect the normal operation of the authorized system or higher priority systems);

When the occupied frequency band is no longer available, the sensing system needs to relinquish these bands to the authorization system or higher priority system in time.

It can be seen that determining the blank frequency is the premise of the cognitive radio system work, and spectrum sensing is one of the important means to determine the white space spectrum. The so-called spectrum sensing refers to the signal judgment by detecting the authorization system on the target spectrum or a higher priority system. Whether the primary system is authorized to occupy the target spectrum, that is, the target spectrum is occupied or idle. However, due to the "hidden terminal" problem caused by the shadow effect, multipath fading and other characteristics, it will lead to the use of a single point aware cognitive radio system to interfere with authorized user communication, and in order to overcome this problem, a single point aware cognitive radio system Need to improve the perception time or use more complex perceptual algorithms, increasing the implementation complexity of the system.

At present, cognitive sensing systems are generally considered to improve the performance of spectrum sensing. The basic principle of collaboration awareness is to improve the perceived performance by eliminating the adverse effects of individual nodes by using the perceived results of collaborative sensing nodes located in multiple geographical locations. The current process of performing the collaboration-aware process is generally as follows: The network management device, such as a base station, configures multiple terminals to perform the sensing of a certain target spectrum, and multiple devices perform spectrum sensing, and the local spectrum sensing result is sent to the network management device. The convergence center of the network management device combines the local sensing results of multiple terminals according to a certain fusion rule to obtain the final cooperative spectrum sensing decision result.

Collaborative awareness can be divided into hard-decision collaborative sensing and soft-decision collaborative sensing according to the combination of local detection information on the sensing nodes and the fusion algorithm used in the fusion center.

In hard decision cooperative sensing, the local detection information reported or interacted by the sensing node is a 1-bit or 2-bit local hard decision result, that is, channel occupancy (0) or idle (1), or a result belonging to a certain area, and the fusion center is based on The local hard decision results of multiple sensing nodes are fused. Common hard decision fusion criteria include criteria such as (and ), or (or ) and voting voting.

In the soft decision cooperative sensing, the local detection information reported or interacted by the sensing node is a multi-bit local soft decision result, and the statistic can be detected for the quantized detection information such as energy, and the fusion center performs the local soft decision result based on the plurality of sensing nodes. Fusion. Common soft decision fusion criteria include linear cooperation, Likelihood Ratio Detection and other integration criteria. Commonly used linear cooperative sensing fusion criteria include MRC (Maximum Ratio Combiner), EGC (Equal Gain Combining), and Select Combining Fusion Rules.

However, according to current research, the choice of the appropriate collaborative sensing sensory node is a premise to ensure the performance of collaborative sensing. For example, when the Voting algorithm is used, when the distance between the sensing nodes and the interference source is the same, if the number of sensing nodes exceeds a certain threshold, the cooperative sensing detection performance will decrease; and when the algorithm is used, the cooperative sensing When the distance between the nodes and the interference source is the same, the cooperative sensing detection performance is greater than the distance inconsistency.

In order to implement the sensing detection, the sensing device (mostly the base station device) needs to scan the alternate frequency point. Considering the bandwidth of the sensing device, the entire detection frequency band cannot be included. Therefore, in the sensing detection, the periodic scanning mode is mostly For the detection of a certain frequency point, it is necessary to wait for a certain period of time before the frequency point can be detected again. In order to avoid the occurrence of an authorization system or a higher priority system at the frequency during the detection period, the method that can be used is the shrinking and detecting period. However, this method obviously causes the current system to invest a large perceived consumption. At the same time, in order to improve the accuracy of the perception detection, During the time of sensing detection, the CR system is required to stop the signal transmission and reception on the channel. When the silence is too frequent, the performance of the CR system is also greatly affected.

In summary, in a cognitive radio system, a method in which a plurality of sensing nodes cooperate with each other to improve the sensing performance is referred to as cooperative sensing, and a plurality of sensing nodes performing cooperative sensing constitute a set of cooperative sensing nodes. How to select nodes in a collaborative awareness node set is an important prerequisite for ensuring collaborative awareness performance. After research, when the sensing node is not selected properly, it will not only improve the sensing performance, but will reduce the performance of collaborative sensing. In addition, when performing perceptual detection, the cycle detection method is generally used. For a certain frequency point, it needs to be detected again after one cycle. In order to find a higher priority system in time, it can be realized by shortening the detection period. However, when the detection period is too short, it will bring a large burden to the detection device, and increase the energy consumption of the sensing detection device. At the same time, in order to improve the accuracy of the sensing detection, the CR system stops the signal transmission and reception on the channel during the sensing detection time. When the silence is too frequent, the performance of the CR system is also greatly affected. Summary of the invention

Embodiments of the present application provide a spectrum sensing method and apparatus in a cognitive radio CR system for improving performance of a CR system.

A spectrum sensing method in a cognitive radio CR system, the method comprising:

The central management device determines a plurality of sensing nodes capable of sensing the target frequency point and geographic location information of the authorization system corresponding to the target frequency point;

The central management device divides the plurality of sensing nodes into a plurality of cooperative sensing clusters according to geographical location information of the authorization system and a preset joint sensing detection probability, where each collaborative sensing cluster includes at least one sensing node, and is different The cooperative sensing cluster does not contain duplicate sensing nodes;

The central management device allocates a sensing task to each of the cooperative sensing clusters, where the sensing task includes time information for performing spectrum sensing on the target frequency point;

The central management device notifies the sensing task assigned to each of the cooperative sensing clusters to the sensing node in the corresponding collaborative sensing cluster to instruct the sensing node to perform spectrum sensing on the target frequency point according to the notified sensing task.

The sensing node receives the sensing task notified by the central management device, where the sensing task includes time information for spectrum sensing of the target frequency point; and the sensing node is the central management device according to the geographic location information of the authorization system and a preset association. The sensing probability is detected, and the plurality of sensing nodes capable of sensing the target frequency point are divided into the sensing nodes included in one of the plurality of cooperative sensing clusters, wherein each of the cooperative sensing clusters includes at least one sensing node, and different cooperation The sensing cluster does not include a repeated sensing node; the sensing task received by the sensing node is a central tube The sensing task assigned by the device to the collaborative sensing cluster to which the sensing node belongs;

The sensing node performs spectrum sensing on the target frequency point according to the sensing task.

A spectrum sensing device in a cognitive radio CR system, the device comprising:

An information acquiring unit, configured to determine a plurality of sensing nodes capable of sensing a target frequency point and geographic location information of an authorization system corresponding to the target frequency point;

a cooperative sensing cluster dividing unit, configured to divide the plurality of sensing nodes into a plurality of cooperative sensing clusters according to geographical location information of the authorization system and a preset joint sensing detection probability, where each collaborative sensing cluster includes at least one Perceiving nodes, and different cooperative sensing clusters do not include duplicate sensing nodes;

a perceptual task allocation unit, configured to allocate a perceptual task to each of the cooperative sensing clusters, where the perceptual task includes time information for performing spectrum sensing on the target frequency point;

The task notification unit is configured to notify the sensing node allocated to each of the cooperative sensing clusters to the sensing node in the corresponding cooperative sensing cluster, to instruct the sensing node to perform spectrum sensing on the target frequency point according to the notified sensing task.

a sensing task receiving unit, configured to receive a sensing task notified by the central management device, where the sensing task includes time information for spectrum sensing of the target frequency point; the sensing node is a central management device according to the geographic location information of the authorized system Pre-set joint sensing probability, the plurality of sensing nodes capable of sensing the target frequency point are divided into sensing nodes included in one of the plurality of cooperative sensing clusters, wherein each collaborative sensing cluster includes at least one sensing a node, and a different sensing-aware cluster does not include a repeated sensing node; the sensing task received by the sensing node is a sensing task allocated by the central management device for the collaborative sensing cluster to which the sensing node belongs;

And a spectrum sensing unit, configured to perform spectrum sensing on the target frequency point according to the sensing task.

In the solution provided by the embodiment of the present application, the central management device determines the location information of the multiple sensing nodes that can sense the target frequency point and the authorization system corresponding to the target frequency point, according to the geographic location information of the authorization system and the preset joint sensing. The detection probability divides the plurality of sensing nodes into a plurality of cooperative sensing clusters, each of the cooperative sensing clusters includes at least one sensing node, and the different cooperative sensing clusters do not include repeated sensing nodes; the central management device allocates each collaborative sensing cluster The sensing task includes the time information of the spectrum sensing of the target frequency point, and the central management device notifies the sensing task assigned to each of the cooperative sensing clusters to the sensing node in the corresponding collaborative sensing cluster, and the sensing node according to the notified sensing task Spectrum sensing of the target frequency. It can be seen that, in the solution, the plurality of sensing nodes capable of sensing the target frequency point are divided into multiple cooperative sensing clusters, and the sensing tasks are dynamically allocated to multiple cooperative sensing clusters, thereby avoiding a certain sensing node and its subordinated area. The performance of the CR system is improved by frequent silent execution due to frequent execution of the sensing task. DRAWINGS

1 is a schematic flowchart of a method provided by an embodiment of the present application;

2 is a schematic flowchart of another method provided by an embodiment of the present application;

3a is a schematic overall flow chart of Embodiment 1 of the present application;

FIG. 3b is a schematic flowchart of a collaborative sensing cluster division process according to Embodiment 1 of the present application;

3c is a schematic diagram of a correspondence between a sensing task and a detection time period according to Embodiment 1 of the present application;

FIG. 3 is a schematic diagram of performing a sensing task in units of clusters according to Embodiment 1 of the present application; FIG.

3e is a schematic diagram of performing a sensing task in units of clusters according to Embodiment 1 of the present application;

4a is a schematic diagram of an information interaction process according to Embodiment 2 of the present application;

FIG. 4b is a schematic diagram of a perceptual task allocation according to Embodiment 2 of the present application;

FIG. 5 is a schematic structural diagram of a device according to Embodiment 3 of the present application; FIG.

6 is a schematic structural diagram of a device according to Embodiment 4 of the present application;

7 is a schematic structural diagram of a device provided in Embodiment 5 of the present application;

FIG. 8 is a schematic structural diagram of a device according to Embodiment 6 of the present application. detailed description

In order to improve the performance of the CR system, the embodiment of the present application provides a spectrum sensing method in a CR system.

Referring to FIG. 1 , a spectrum sensing method in a CR system for a network side provided by an embodiment of the present application includes the following steps:

Step 10: The central management device determines a plurality of sensing nodes capable of sensing the target frequency point and geographic location information of the authorization system corresponding to the target frequency point;

Step 11: The central management device divides the plurality of sensing nodes into a plurality of cooperative sensing clusters according to the geographic location information of the authorized system and the preset joint sensing detection probability, each collaborative sensing cluster includes at least one sensing node, and different cooperation The perceptual cluster does not contain duplicate perceptual nodes;

Step 12: The central management device allocates a sensing task to each of the cooperative sensing clusters, and the sensing task includes time information for spectrum sensing of the target frequency points. In order to balance the sensing tasks, when the sensing tasks are assigned to each collaborative sensing cluster, So that each cooperative sensing cluster does not perform spectrum sensing in all time periods that need to be subjected to spectrum sensing; the so-called spectrum sensing refers to determining the authorized primary system or higher priority by detecting the signal of the authorized system or higher priority system at the target frequency point. Whether the system occupies the target frequency point, that is, determines whether the target frequency point is occupied or idle.

Step 13: The central management device notifies the sensing task assigned to each of the cooperative sensing clusters to the sensing node in the corresponding cooperative sensing cluster to instruct the sensing node to perform spectrum sensing on the target frequency point according to the notified sensing task. Specifically, in step 10, the central management device determines the location information of the plurality of sensing nodes that can sense the target frequency point and the authorization system corresponding to the target frequency point, and the specific implementation may be as follows:

The central management device selects, according to the stored radio frequency capability information of each sensing node, a plurality of sensing nodes that can perceive the target frequency point from each sensing node;

The central management device acquires geographic location information of the authorization system corresponding to the target frequency point from the geographic location information base of the authorization system.

In step 11, the central management device divides the plurality of sensing nodes into multiple cooperative sensing clusters according to the geographical location information of the authorized system and the preset joint sensing detection probability, and the specific implementation may be as follows:

A. The central management device divides the cooperative sensing clusters including the X sensing nodes according to the following method: determining the number of sensing nodes that are capable of sensing the target frequency point and the distance from the authorized system is not greater than the preset distance value.

X-1

Num _ d" , if Num _d _x ⁿ - ^i ^Num _ i mod > 0 , then Nw - a cooperative sensing cluster containing x sensing nodes, each in a cooperative sensing cluster containing X sensing nodes The sensing node is a sensing node whose distance from the authorized system is not greater than a preset distance value; otherwise, it is determined that the collaborative sensing cluster including the X sensing nodes cannot be divided;

Num-X Num _d _x ⁿ - *N mod

, w _ z is the sense of collaboration that contains . perceptual nodes, where ―

The number of clusters; the initial value of X is 1; the preset distance value is related to the preset joint sensing probability and the current value of X;

X

Num _ node _ total - ^ i *Num _i > X + \

B. If ' ⁼¹ , add X to the value of 1 and return to step A. Otherwise, the process ends; where ^^ - ^Wi1⁄2fe - is the number of multiple sensing nodes that can perceive the target frequency.

The above method for determining the preset distance value can be as follows:

The central management device reads a preset comparison table between the number of sensing nodes and the farthest distance requirement, and the comparison table includes multiple mapping relationships, and each mapping relationship is the joint sensing detection probability and the number of sensing nodes and the distance authorization system. Mapping of distance values;

The central management device searches for the farthest distance value of the distance authorization system corresponding to the preset joint detection detection probability and the current X value from the read comparison table, and determines the farth distance value of the found distance authorization system as the pre Set the distance value.

Specifically, in step 12, the central management device allocates a sensing task to each collaborative sensing cluster, and the specific implementation may be as follows:

The central management device divides the plurality of cooperative sensing clusters into at least one collaborative sensing cluster, and each of the collaborative sensing clusters The cooperative sensing cluster includes the same number of sensing nodes; each of the collaborative sensing clusters is separately assigned a sensing task, and the cooperative sensing clusters in each of the collaborative sensing clusters perform sensing tasks assigned to the corresponding collaborative sensing clusters; or

The central management device allocates a perceptual task for each collaborative sensing cluster.

The time information of the spectrum sensing of the target frequency point included in the sensing task in the step 12 may include: a detection period and a detection period information; wherein, the detection period indicates a time period in which the spectrum sensing is performed on the target frequency point; The time period during which the target frequency point is spectrally perceived during the detection period.

Preferably, after the central management device notifies the sensing task assigned to each of the cooperative sensing clusters to the sensing node in the corresponding cooperative sensing cluster, the central management device receives the spectrum sensing performed by the sensing node on the target frequency point. Perceive the result; perform fusion processing on the received sensing result to obtain whether the authorization system occupies the judgment result of the target frequency point, and send the determination result to each node in the system.

Referring to FIG. 2, the spectrum sensing method in the CR system provided by the terminal side in the embodiment of the present application includes the following steps:

Step 20: The sensing node receives the sensing task notified by the central management device, where the sensing task includes time information for spectrum sensing of the target frequency point. The sensing node is the central management device according to the geographic location information of the authorized system and the preset joint sensing. Detecting a probability, dividing a plurality of sensing nodes capable of sensing a target frequency point into a sensing node included in one of the plurality of cooperative sensing clusters, wherein each of the cooperative sensing clusters includes at least one sensing node, and different collaborative sensing The cluster does not include a repeated sensing node; the sensing task received by the sensing node is a sensing task assigned by the central management device to the collaborative sensing cluster to which the sensing node belongs;

Step 21: The sensing node performs spectrum sensing on the target frequency point according to the sensing task.

Specifically, the time information of the spectrum sensing performed by the sensing task may include: a detection period and a detection period information, where the detection period indicates a time period in which spectrum sensing is performed on the target frequency point, and the detection time period information is represented in A time period in which the target frequency is subjected to spectrum sensing during the detection period; in this case, the sensing node performs spectrum sensing on the target frequency point according to the sensing task, and the specific implementation may be: the detection time of the sensing node in the detection period Spectrum sensing is performed on the target frequency point in the segment.

Preferably, after the sensing node performs spectrum sensing on the target frequency point according to the sensing task, the sensing node reports the sensing result of the spectrum sensing on the target frequency point to the central management device; whether the sensing node receives the authorization system delivered by the central management device. The decision result of occupying the target frequency.

The present application is described below in conjunction with specific embodiments:

Embodiment 1:

This embodiment proposes a mechanism for a multi-collaborative sensing cluster to complete a sensing task. In order to facilitate subsequent presentation, in this solution, a concept of a collaborative sensing cluster is introduced, and a collaborative sensing cluster is defined to perform collaborative sensing at a certain detection time. The X-point cooperative sensing cluster formed by the X sensing nodes, where ≥ι; multiple X-point cooperative sensing clusters, together form an X-point cooperative sensing cluster. In addition, in the present scheme, Table 1 is introduced to list the maximum distance value of each sensing node required to be authorized from the authorized system when a different number of sensing nodes are cooperatively aware for a certain joint sensing probability requirement. In the second behavior example of Table 1, when the joint sensing detection probability requirement is 1, when the number of sensing nodes is one, the distance of the node from the authorization system cannot be exceeded. Table 1 can be derived from measured data, or it can be modified according to system level simulation and appropriate according to the actual environment.

Table 1. Comparison table between the number of perceived nodes and the farthest distance requirement

The specific implementation process of this solution is shown in Figure 3a:

Step S1: For a certain frequency point f, the central management unit acquires geographical location information of a plurality of sensing nodes capable of sensing the frequency point f and a transmitting station of the authorization system that can use the frequency point f;

According to the obtained geographical location information, the distance between each sensing node and the authorization system is determined, and the distance table is arranged according to the distance, and the distance table is shown in Table 2. The sensing node number is only its sequence number, and the sensing node itself Corresponding to the identifier, if the sensing node is a base station, the sensing node number corresponds to the cell identifier of the base station;

Perceptual node coding 1 2 Perceptual node total number ( Num_node_total ) Perceptual node and

Authorized system distance cl ₂ d from

Table 2. Perceptual Node Distance Authorization System Distance Table

Step S2: The central management unit divides the plurality of sensing nodes into a plurality of cooperative sensing clusters;

Here, under the premise of satisfying the joint sensing probability, the cooperative sensing cluster is divided according to the principle that the number of cooperative sensing clusters is the largest. The above-mentioned sensing node is divided into multiple cooperative sensing clusters, taking the joint sensing detection probability as an example, and the execution steps are specifically illustrated in FIG. 3b: The division of the single-point cooperative sensing cluster: Assume that all the above-mentioned sensing nodes satisfy and authorize the system. The number of sensing nodes whose distance is less than or equal to is ^^-. If ^^- ^>Q , the single-point cooperative sensing cluster is divided into Num_l; otherwise, the single-point cooperative sensing cluster cannot be formed; where Num = _m — . To continue to search for two points of collaborative awareness cluster: ^TM-" ⁰ ^-^^ ^TM- ¹ ^, continue to search for two-point cooperative sensing scheme, and vice versa, clustering cluster ends; two-point collaborative sensing cluster: assuming all the above-mentioned sensing nodes The number of sensing nodes that satisfy the distance from the authorized system is less than or equal to W-. If ^ - _^TM-l °d2>0, then _Num _ ₂ two-point cooperative sensing clusters can be formed; otherwise, two can not be formed. Point cooperative sensing cluster; where Λ^-2 = μ _ _M^_l Gd2 _;

According to the above method, a cooperative sensing cluster composed of the number of other sensing nodes is divided. Generally, for the X sensing nodes cooperative sensing clusters, it is assumed that the number of sensing nodes satisfying the distance less than or equal to all of the above nodes is ^Num _dx ⁰ ,

It can form Num X X nodes cooperative sensing clusters, otherwise, no

Num — d _x . Si Num mod

The method forms an X-point cooperative sensing cluster;

Num _ node _ total - i ^Num _ ;' > + 1 Determine whether to continue to search for X+l nodes cooperative awareness clusters: If “ ― " , continue to search for X+1 point cooperative sensing clusters; otherwise, divide clusters End;

Step S3: The central management unit allocates a sensing task to each of the cooperative sensing clusters, and notifies the sensing tasks assigned to each of the collaborative sensing clusters to the sensing nodes in the corresponding collaborative sensing clusters;

The sensing task is measured in time, as shown in Fig. 3c, and the detection task of the corresponding frequency point f is completed in each detection time period. Sensing_period_l corresponds to the first detection time period, that is, the first detection time period is represented, and T represents the detection period. The detection period can be the same or can be set separately, that is, T1 can be equal to T2 or can be set independently; Distribution method:

Method 1: As shown in FIG. 3d, the sensing task is performed in units of clusters, for example, for the first sensing detection period, The sensing task is completed by all the single-point cooperative sensing clusters; for the second sensing detection time period, the sensing tasks are completed by all the two-point cooperative sensing clusters.

Method 2: As shown in FIG. 3e, performing a perceptual task in units of clusters, such as a single-point cooperative sensing cluster of No. 1, corresponding to the first detection task, and a single-point cooperative sensing cluster of No. 2 corresponding to the second detection task.

According to the foregoing allocation method, the sensing task can be distributed into multiple clusters, and the detection period of each cooperative sensing cluster can be increased under the requirement of the joint sensing detection probability, which can greatly reduce the detection detection. Consumption.

Step S4: Each sensing node performs spectrum sensing on the frequency point f according to the notified sensing task, and reports the sensing result to the central management unit, and the central management unit performs fusion processing on the received sensing result to obtain whether the authorized system occupies the frequency point f. The result of the decision is sent to the nodes in the system.

During each detection period, the sensing nodes in the cooperative sensing cluster will perceive the sensing result to a central management unit, and the central management unit further fuses the result, and feeds the final judgment result to each node in the system, thereby The whole network obtains the usage of the frequency f. If the sensing task is assigned according to the method 2 in the step axis S3, the result of the plurality of X-sensing nodes collaborating on the cluster, and further joint processing is required, that is, the result of each cooperative sensing cluster decision is again subjected to a soft decision or a hard decision. The collaborative processing, the specific method and the collaborative processing of multiple sensing nodes are the same.

Embodiment 2:

1 Set the current Num_node_total=4 sensing nodes, wherein the sensing node 1, the sensing node 2, and the sensing node 3 are all base stations, the identity identifier is composed of the system ID and the cell ID, the node 4 is the terminal, and the identity identifier is determined by the system ID, the cell ID, The terminal ID is composed. In this embodiment, it is assumed that the information of the above four sensing nodes is as shown in Table 3. The detected frequency is fl, and the geographic location value information of the base station of the authorized system using the frequency is (latitude _X, longitude _Y).

Table 3. Node identity and location information

As shown in Figure 4a, the specific process is as follows:

Step 1: The central management unit acquires a sensing node that supports the sensing of the frequency point fl and an authorization that may use the frequency point f Geographical location information of the system's transmitting station;

According to the obtained geographical location information, the distance between each sensing node and the authorization system is determined, and the distance table is arranged according to the distance, and the distance table is shown in Table 3. The node number 1 corresponds to the node whose identity is XXXXXXX 1. Node number 2 corresponds to a node whose identity is XXXXXXX3, node number 3 corresponds to a node whose identity is XXXXXXX3 UE ID, and node number 4 corresponds to a node whose identity is XXXXXXX2;

Table 3. Perceptual Node and Authorization System Distance Table Step 2: Divide the Collaborative Awareness Cluster. According to Table 1, it is assumed that the joint sensing probability that needs to be met currently is , and when the different number of sensing nodes cooperate, the farthest distance required to achieve the joint sensing probability is shown in Table 4:

Table 4. Comparison table between the number of perceived nodes and the farthest distance requirement

The division of the single-point cooperative sensing cluster: Assume that the number of nodes satisfying the distance from the authorized system is ^^- =1 among all the above nodes, and if N _U m_d? >0, the single-point cooperative sensing cluster is divided into Numj ^, consists of node number 1 alone; where 丽 = _ .

Determine whether to continue to search for two points of collaborative awareness clusters: after judging 4-1 > 2, continue to search for two points of collaborative awareness clusters;

Two-point cooperative sensing cluster: Assume that among all the above nodes, the number of nodes that meet the distance from the authorized system is less than or equal to ^Num - = 2, and if ^ - _^ ^> 0, it can constitute _Num _ _{2 = 1} two-point cooperative sensing Cluster, consisting of node numbers 2 and 3 to form a two-point cooperative sensing cluster, where Λ^-2 = ^_ _Λ^_1 0 (12 _{; to} determine whether to continue to search for three-point cooperative sensing cluster: judged, ^Nwn - ^node - ^t0tal -Num_\-2*Num_2<3 ^ to end the cluster; Step 3: The central management unit allocates a perceptual task for each collaborative sensing cluster;

Perceive tasks are distributed among multiple collaborative awareness clusters. As shown in FIG. 4b, the single-point cooperative sensing cluster, that is, the base station whose identity is XXXXXXX1 completes the sensing task in the first detection period, and the two-point cooperative sensing cluster, that is, the base station identified by the identifier XXXXXXX3 and the terminal whose identifier is XXXXXXX3_UE_ID The two-point cooperative sensing cluster is composed, the detection task is completed in the second detection period, and the like. Under the assumptions, it can be seen that for each cooperative sensing cluster, the detection period can be extended by a factor of two, which can reduce the consumption of perceptual detection by 50%.

Step 4: Notifying the sensing task assigned to each collaborative sensing cluster to the sensing node in the corresponding collaborative sensing cluster; Step 5: Each sensing node performs spectrum sensing on the frequency point f according to the notified sensing task, and the sensing result is 4艮 to the central management unit;

Step 6: The central management unit performs fusion processing on the received sensing result to obtain whether the authorization system occupies the judgment result of the frequency fl, and sends the determination result to each node in the system.

Referring to FIG. 5, a third embodiment of the present application provides a spectrum sensing device in a CR system, where the device includes: an information acquiring unit 50, configured to determine a plurality of sensing nodes capable of sensing a target frequency point, and corresponding to the target frequency point. Geographical location information of the authorization system;

The cooperative sensing clustering unit 51 is configured to divide the plurality of sensing nodes into a plurality of cooperative sensing clusters according to geographical location information of the authorization system and a preset joint sensing detection probability, where each collaborative sensing cluster includes at least a perceptual node, and the different perceptual sensing clusters do not include repeated perceptual nodes;

a perceptual task allocation unit 52, configured to allocate a perceptual task to each of the cooperative sensing clusters, where the perceptual task includes time information for performing spectrum sensing on the target frequency point;

The task notification unit 53 is configured to notify the sensing node allocated to each of the cooperative sensing clusters to the sensing node in the corresponding cooperative sensing cluster, to instruct the sensing node to perform spectrum sensing on the target frequency point according to the notified sensing task.

Further, the information acquiring unit 50 is configured to:

Selecting, according to the stored radio frequency capability information of each sensing node, a plurality of sensing nodes capable of sensing the target frequency point from each sensing node;

Obtaining, from the authorization system geographic location information database, geographic location information of the authorization system corresponding to the target frequency point. Further, the cooperative sensing cluster dividing unit 51 is configured to perform the following steps:

A. The cooperative sensing cluster including the X sensing nodes is divided according to the following method: determining that the number of sensing nodes in the plurality of sensing nodes capable of sensing the target frequency is not greater than the preset distance by the authorized system is

Num d", if Num _ d _x " *Num- mod > 0 , then divide the »«_Jr cooperative sensing clusters containing X sensing nodes, and the sensing nodes in the cooperative sensing clusters each containing X sensing nodes are Little distance from the authorization system A perceptual node with a distance value; it is impossible to divide a cooperative sensing cluster containing X sensing nodes;

Num -' is the number of cooperative sensing clusters including i sensing nodes; the initial value of X is 1; the preset distance value is related to a preset joint sensing detection probability and a current X value;

Num _node _total - i *N m _i > X + 1

B. If _ _ '= ι ", the value of X is incremented by 1, and the process returns to step A. Otherwise, the process ends; wherein N - node total is the number of the plurality of sensing nodes capable of sensing the target frequency point.

Further, the cooperative sensing cluster dividing unit 51 is configured to: determine the preset distance value according to the following method:: read a preset comparison table between the number of sensing nodes and the farthest distance requirement relationship, where the comparison table includes multiple Strip mapping relationship, each mapping relationship is a mapping relationship between the joint sensing detection probability and the number of sensing nodes and the farthest distance value of the distance authorization system;

The farthest distance value of the distance authorization system corresponding to the value of the current X is searched from the comparison table, and the farth distance value of the found distance authorization system is determined as the preset distance value.

Further, the sensing task allocation unit 52 is configured to:

Dividing the plurality of cooperative sensing clusters into at least one cooperative sensing cluster group, wherein the cooperative sensing clusters in each collaborative sensing cluster group comprise the same number of sensing nodes; respectively, assigning sensing tasks to each of the collaborative sensing clusters, each The collaborative sensing clusters in the collaborative sensing cluster perform the perceptual tasks assigned to the corresponding collaborative sensing clusters; or

Perceived tasks are assigned to each collaborative awareness cluster.

Further, the time information includes: a detection period and a detection period information;

The detection period represents a time period in which spectrum sensing is performed on the target frequency point, and the detection time period information represents a time period in which the target frequency point is subjected to spectrum sensing during the detection period.

Further, the device further includes:

The data processing unit 54 is configured to: after the sensing task assigned to each of the cooperative sensing clusters is notified to the sensing node in the corresponding cooperative sensing cluster, receive a sensing result reported by the sensing node to perform spectrum sensing on the target frequency point; Performing fusion processing on the received sensing result to obtain whether the authorization system occupies the determination result of the target frequency point, and sends the determination result to each node in the system.

Referring to FIG. 6, a fourth embodiment of the present application provides a spectrum sensing device in a CR system, where the device includes: a sensing task receiving unit 60, configured to receive a sensing task notified by a central management device, where the sensing task includes a target frequency point. Performing spectrum sensing time information; the sensing node is a central management device, according to the geographic location information of the authorization system and a preset joint sensing detection probability, dividing the plurality of sensing nodes capable of sensing the target frequency into multiple collaborations Perceptual nodes included in one of the collaborative sensing clusters after the cluster is perceived, wherein each of the collaborative sensing clusters includes One less perceptual node, and the different perceptual sensing clusters do not include repeated perceptual nodes; the perceptual tasks received by the perceptual nodes are perceptual tasks assigned by the central management device to the cooperative sensing clusters to which the perceptual nodes belong;

The spectrum sensing unit 61 is configured to perform spectrum sensing on the target frequency point according to the sensing task.

Further, the spectrum sensing unit 61 is configured to:

The time information includes: a detection period and a detection period information, where the detection period indicates a time period in which spectrum sensing is performed on the target frequency point, and the detection period information indicates that the detection period is When the target frequency point performs the spectrum sensing period, the target frequency point is subjected to spectrum sensing during the detection period of the detection period.

Further, the device further includes:

The result obtaining unit 62 is configured to report the sensing result of performing spectrum sensing on the target frequency point to the central management device after the spectrum sensing is performed on the target frequency point according to the sensing task;

Whether the authorization system delivered by the receiving center management device occupies the judgment result of the target frequency point.

Referring to FIG. 7, a fifth embodiment of the present application provides a spectrum sensing device in a CR system, where the device includes: a processor 70, configured to determine a plurality of sensing nodes capable of sensing a target frequency point, and an authorization corresponding to the target frequency point. Geographical location information of the system; dividing the plurality of sensing nodes into a plurality of cooperative sensing clusters according to geographical location information of the authorization system and a preset joint sensing detection probability, each collaborative sensing cluster including at least one sensing node And the different perceptual sensing clusters do not include repeated perceptual nodes; each of the cooperative sensing clusters is assigned a perceptual task, the perceptual tasks include time information for spectrum sensing of the target frequency points; each collaborative sensing cluster will be allocated The sensing task is notified to the sensing node in the corresponding cooperative sensing cluster by the transceiver 71, so as to indicate that the sensing node that the sensing node is in the notification performs spectrum sensing on the target frequency point;

The transceiver 71 is configured to receive and transmit data under the control of the processor 70.

Further, the processor 70 is configured to:

Obtaining, from the authorization system geographic location information database, geographic location information of the authorization system corresponding to the target frequency point. Further, the processor 70 is configured to perform the following steps:

Num _node _total - i *N m _i > X + 1

Further, the processor 70 is configured to:

Perceived tasks are assigned to each collaborative awareness cluster.

Further, the processor 70 is further configured to: after the sensing task allocated for each cooperative sensing cluster is notified to the sensing node in the corresponding cooperative sensing cluster, receive the spectrum reported by the sensing node to the target frequency point. Perceived perceptual result; performing fusion processing on the received perceptual result, obtaining whether the authorization system occupies the judgment result of the target frequency point, and transmitting the determination result to each node in the system.

Here, in FIG. 7, the bus architecture may include any number of interconnected buses and bridges, specifically linked by one or more processors represented by processor 70 and various circuits of memory represented by memory 72. The bus architecture can also link various other circuits such as peripherals, voltage regulators, and power management circuits, which are well known in the art and, therefore, will not be further described herein. The bus interface provides an interface. Transceiver 71 can be a plurality of components, including a transmitter and a receiver, providing means for communicating with various other devices over the transport interface. The processor 70 is responsible for managing the bus architecture and the usual processing, and the memory 72 can store the processor 70 for execution. The data used during the operation.

The processor 70 is responsible for managing the bus architecture and general processing, and the memory 72 can store data used by the processor 70 in performing operations.

Referring to FIG. 8, a sixth embodiment of the present application provides a spectrum sensing device in a CR system, where the device includes: a processor 80, configured to receive, by a transceiver 81, a sensing task notified by a central management device, where the sensing task includes a target Performing spectrum sensing time information on the frequency point; the sensing node is configured by the central management device to divide the plurality of sensing nodes capable of sensing the target frequency point according to the geographic location information of the authorization system and the preset joint sensing detection probability Perceptual nodes included in one of the cooperative sensing clusters, wherein each of the cooperative sensing clusters includes at least one sensing node, and the different cooperative sensing clusters do not include repeated sensing nodes; the sensing nodes receive the sensing The task is a perceptual task allocated by the central management device to the cooperative sensing cluster to which the sensing node belongs; #^ according to the sensing task, performing spectrum sensing on the target frequency point;

The transceiver 81 is configured to receive and transmit data under the control of the processor 80.

Further, the processor 80 is configured to:

Further, the processor 80 is further configured to:

After performing the spectrum sensing on the target frequency point according to the sensing task, the sensing result of the spectrum sensing of the target frequency point is reported to the central management device; whether the authorization system delivered by the receiving central management device occupies the The judgment result of the target frequency point.

In Figure 8, the bus architecture can include any number of interconnected buses and bridges, specifically linked by one or more processors represented by processor 80 and various circuits of memory represented by memory 82. The bus architecture can also link various other circuits such as peripherals, voltage regulators, and power management circuits, which are well known in the art and, therefore, will not be further described herein. The bus interface provides an interface. The transceiver 81 can be a plurality of components, including a transmitter and a receiver, providing means for communicating with various other devices on the transport interface. The processor 80 is responsible for managing the bus architecture and the usual processing, and the memory 82 can store data used by the processor 80 in performing operations.

The processor 80 is responsible for managing the bus architecture and the usual processing, and the memory 82 can store data used by the processor 80 in performing operations.

In summary, the beneficial effects of the application include: In the solution provided by the embodiment of the present application, the central management device determines the location information of the multiple sensing nodes that can sense the target frequency point and the authorization system corresponding to the target frequency point, according to the geographic location information of the authorization system and the preset joint sensing. The detection probability divides the plurality of sensing nodes into a plurality of cooperative sensing clusters, each of the cooperative sensing clusters includes at least one sensing node, and the different cooperative sensing clusters do not include repeated sensing nodes; the central management device allocates each collaborative sensing cluster The sensing task includes the time information of the spectrum sensing of the target frequency point, and the central management device notifies the sensing task assigned to each of the cooperative sensing clusters to the sensing node in the corresponding collaborative sensing cluster, and the sensing node according to the notified sensing task Spectrum sensing of the target frequency. It can be seen that, in the solution, the plurality of sensing nodes capable of sensing the target frequency point are divided into multiple cooperative sensing clusters, and the sensing tasks are dynamically allocated to multiple cooperative sensing clusters, thereby avoiding a certain sensing node and its subordinated area. The performance of the CR system is improved by frequent silent execution due to frequent execution of the sensing task.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present application. It will be understood that each process and/or block of the flowchart illustrations and/or FIG. These computer program instructions can be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing device to produce a machine for the execution of instructions for execution by a processor of a computer or other programmable data processing device. Means for implementing the functions specified in one or more of the flow or in a block or blocks of the flow chart.

The computer program instructions can also be stored in a computer readable memory that can direct a computer or other programmable data processing device to operate in a particular manner, such that the instructions stored in the computer readable memory produce an article of manufacture comprising the instruction device. The apparatus implements the functions specified in one or more blocks of a flow or a flow and/or block diagram of the flowchart.

These computer program instructions can also be loaded onto a computer or other programmable data processing device such that a series of operational steps are performed on a computer or other programmable device to produce computer-implemented processing for execution on a computer or other programmable device. The instructions provide steps for implementing the functions specified in one or more of the flow or in a block or blocks of a flow diagram.

Although the preferred embodiment of the present application has been described, those skilled in the art can make additional changes and modifications to the embodiments once they are aware of the basic inventive concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and the modifications and

It will be apparent to those skilled in the art that various modifications and changes can be made in the present application without departing from the spirit and scope of the application. Thus, it is intended that the present invention cover the modifications and variations of the present invention.

Claims

Rights request

A spectrum sensing method in a cognitive radio CR system, the method comprising: the central management device determining a plurality of sensing nodes capable of sensing a target frequency point and a geographical location of an authorization system corresponding to the target frequency point Information

The method according to claim 1, wherein the central management device determines the plurality of sensing nodes that can be aware of the target frequency and the geographic location information of the authorization system corresponding to the target frequency, and specifically includes:

The method according to claim 1, wherein the central management device divides the plurality of sensing nodes into multiple collaborations according to geographical location information of the authorization system and a preset joint sensing detection probability. Perceptual clusters, including:

A. The central management device divides the cooperative sensing clusters that include the X sensing nodes according to the following method: determining that the sensing nodes of the plurality of sensing nodes that can sense the target frequency point are not greater than the preset distance value by the authorized system The number is Nwn d", and if Num _ d _x " *Num mod > 0 , a cooperative sensing cluster containing X sensing nodes is divided, and each sensing node in the cooperative sensing cluster containing X sensing nodes is The sensing system is not more than the sensing node of the preset distance value; otherwise, it is determined that the collaborative sensing cluster including the X sensing nodes cannot be divided;

Num-X Num _ d *Num mod

Num

Wherein, ― ' is the number of cooperative sensing clusters including i sensing nodes; the initial value of X is 1; the preset distance value is related to a preset joint sensing detection probability and a current X value; Num _node _total - i *N m _i > X + 1

The method of claim 3, wherein the determining the preset distance value comprises: the central management device reading a preset comparison of the number of sensing nodes and the farthest distance requirement relationship, the comparison The table includes multiple mapping relationships, and each mapping relationship is a mapping relationship between the joint sensing detection probability and the number of sensing nodes and the farthest distance value from the authorization system;

The central management device searches the comparison table for the farthest distance value of the distance authorization system corresponding to the preset joint detection detection probability and the current X value, and determines the farth distance value of the found distance authorization system as the preset distance. value.

The method according to claim 1, wherein the central management device allocates the sensing task to each of the collaborative sensing clusters, and specifically includes:

The central management device divides the plurality of cooperative sensing clusters into at least one cooperative sensing cluster group, and the cooperative sensing clusters in each collaborative sensing cluster group comprise the same number of sensing nodes; respectively, assigning sensing tasks to each of the collaborative sensing clusters The cooperative sensing clusters in each of the collaborative sensing clusters perform the sensing tasks assigned to the corresponding collaborative sensing clusters; or, the central management device allocates the sensing tasks to each of the collaborative sensing clusters.

The method according to any one of claims 1 to 5, wherein the time information comprises: a detection period and a detection period information;

The method according to any one of claims 1 to 5, further comprising, after the central management device notifies the sensing task assigned to each of the cooperative sensing clusters to the sensing node in the corresponding collaborative sensing cluster, further comprising :

The central management device receives the sensing result of the spectrum sensing performed by the sensing node on the target frequency point, and performs fusion processing on the received sensing result to obtain whether the authorization system occupies the determination result of the target frequency point, and the The decision result is sent to each node in the system.

A spectrum sensing method in a cognitive radio CR system, the method comprising: the sensing node receiving a sensing task notified by the central management device, wherein the sensing task includes time information for performing spectrum sensing on the target frequency point; The sensing node divides, by the central management device, the plurality of sensing nodes capable of sensing the target frequency point into one of the plurality of cooperative sensing clusters according to the geographical location information of the authorized system and the preset joint sensing detection probability. a perceptual node included in the cluster, wherein each of the cooperative sensing clusters includes at least one perceptual node, and the different perceptual sensing clusters do not include repeated perceptual nodes; the perceptual node receives the perceptual task as the central management device for the perceptual A perceptual task assigned by the collaborative sensing cluster to which the node belongs; The sensing node performs spectrum sensing on the target frequency point according to the sensing task.

The method according to claim 8, wherein the time information includes: a detection period and a detection period information; the detection period indicates a time period during which spectrum sensing is performed on the target frequency point, The detection period information represents a time period in which the target frequency point is subjected to spectrum sensing during the detection period;

The sensing node performs spectrum sensing on the target frequency point according to the sensing task, and specifically includes:

The method according to claim 8 or 9, wherein after the sensing node performs spectrum sensing on the target frequency point according to the sensing task, the method further includes:

And the sensing node receives the sensing result of the spectrum sensing on the target frequency point to the central management device; and the sensing node receives the determination result of whether the authorization system delivered by the central management device occupies the target frequency point.

A spectrum sensing device in a cognitive radio CR system, the device comprising: an information acquiring unit, configured to determine a plurality of sensing nodes capable of sensing a target frequency point and an authorization system corresponding to the target frequency point Geographic location information;

The device according to claim 11, wherein the information acquiring unit is configured to:

Obtaining, from the authorization system geographic location information database, geographic location information of the authorization system corresponding to the target frequency point.

The apparatus according to claim 11, wherein the cooperative sensing cluster dividing unit is configured to perform the following steps:

Num d", if Num _ d _x " *Num― mod > 0 , then divide the »« _Jr cooperative sensing clusters containing X sensing nodes, and the sensing nodes in each collaborative sensing cluster containing X sensing nodes are Little distance from the authorization system A perceptual node with a distance value; it is impossible to divide a cooperative sensing cluster containing X sensing nodes;

Num _node _total - i *N m _i > X + 1

The apparatus according to claim 13, wherein the cooperative sensing cluster dividing unit is configured to: determine the preset distance value according to the following method:

Reading a preset comparison table between the number of sensing nodes and the farthest distance requirement, the comparison table includes multiple mapping relationships, and each mapping relationship is a joint sensing detection probability and the number of sensing nodes and the farthest distance value of the distance authorization system. Mapping relationship;

The device according to claim 11, wherein the perceptual task allocation unit is configured to: divide the plurality of cooperative sensing clusters into at least one collaborative sensing cluster, and cooperate in each collaborative sensing cluster The number of the perceptual nodes included in the perceptual cluster is the same; the perceptual task is assigned to each of the cooperative sensing clusters, and the cooperative sensing clusters in each of the cooperative sensing clusters are performed as the perceptual tasks assigned to the corresponding cooperative sensing clusters; or

Perceived tasks are assigned to each collaborative awareness cluster.

The device according to any one of claims 11-15, wherein the time information comprises: a detection period and a detection period information;

17. The device of any of claims 11-15, wherein the device further comprises:

a data processing unit, configured to: after the sensing task assigned to each of the cooperative sensing clusters is notified to the sensing node in the corresponding cooperative sensing cluster, receive the sensing result of the spectrum sensing performed by the sensing node on the target frequency point; The received sensing result is subjected to a fusion process to obtain whether the authorization system occupies the decision result of the target frequency point, and the decision result is sent to each node in the system.

A spectrum sensing device in a cognitive radio CR system, the device comprising: a sensing task receiving unit, configured to receive a sensing task notified by a central management device, wherein the sensing task comprises performing spectrum on a target frequency point Perceived time information; the sensing node is a central management device according to the geographic of the authorization system The location information and the preset joint sensing probability, the plurality of sensing nodes capable of sensing the target frequency point are divided into the sensing nodes included in one of the plurality of cooperative sensing clusters, wherein each of the cooperative sensing clusters includes At least one sensing node, and the different cognitive sensing clusters do not include the repeated sensing nodes; the sensing tasks received by the sensing nodes are the sensing tasks allocated by the central management device to the collaborative sensing clusters to which the sensing nodes belong;

The device according to claim 18, wherein the spectrum sensing unit is configured to:

The device according to claim 18 or 19, wherein the device further comprises:

a result obtaining unit, configured to report the sensing result of performing spectrum sensing on the target frequency point to the central management device after performing spectrum sensing on the target frequency point according to the sensing task; Whether the authorization system occupies the judgment result of the target frequency point.