A method for allocating channel resources in a communication and positioning integrated network

Abstract

The application relates to a communication and positioning integrated network channel resource allocation method, belonging to the technical field of communication networks and navigation positioning, and the specific process is as follows: step 1, each resource block is sequentially allocated with a corresponding link based on the maximization of meeting the transmission requirements of each link; step 2, the time-frequency resources are sequentially allocated according to the descending order of the sum of the link resource block occupation; and step 3, the transmission power of each link is optimized by constraining the link signal-to-noise ratio and the maximum transmission power of a node, so as to minimize the average position error bound of the network.

Description

Technical Field

[0001] This invention relates to a method for allocating channel resources in an integrated communication and positioning network, belonging to the fields of communication networks and navigation and positioning technology. Background Technology

[0002] An integrated communication and positioning network refers to a network in which each node uses wireless links to exchange information and perform relative measurements between nodes. By combining the measurement information between the nodes and external anchor points, collaborative positioning between network nodes can be achieved, which can provide support for scenarios such as vehicle-to-everything (V2X) networks, satellite networks, and mobile robot networks.

[0003] In integrated communication and positioning networks, channel resource allocation strategies have a significant impact on both network communication and positioning performance. On the one hand, the time-frequency resource allocation of inter-node links directly affects the data transmission rate of each link; on the other hand, link signal bandwidth and transmission power further affect link measurement accuracy, thus determining the overall cooperative positioning performance of the network.

[0004] Conventional network resource scheduling methods typically focus only on communication performance optimization, with little consideration for the impact of resource allocation strategies on positioning performance. Resource scheduling methods with positioning performance as the optimization objective have received limited research. The paper "Joint Power and Bandwidth Allocation in Wireless Cooperative Localization Networks" published in the October 2016 issue of IEEE Transactions on Wireless Communications, Volume 15, Issue 10, pp. 6527-6540, mentions a joint power and bandwidth allocation method based on trust region optimization. However, this method is sensitive to initial resource allocation results, has a slow convergence speed, and struggles to meet the requirements for rapid channel resource scheduling when the number of network links is large and node dynamics are high. Therefore, it is necessary to research a communication-positioning integrated network resource scheduling method that is independent of initial values, has a fast convergence speed, and can simultaneously consider both communication and positioning performance. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a channel resource allocation method for an integrated communication and positioning network. This method adopts a two-stage scheduling framework to jointly allocate time-frequency resources and link transmission power in the integrated communication and positioning network.

[0006] The technical solution for implementing the present invention is as follows: In a first aspect, the present invention provides a method for allocating channel resources in a communication and positioning integrated network, the specific process of which is as follows: Step 1: Based on maximizing the transmission requirements of each link, allocate the corresponding link to each resource block in turn; Step 2: Allocate the specific time-frequency resources in descending order of the total total resource block usage of the link; Step 3: With the goal of minimizing the network average location error bound, optimize the transmission power of each link by constraining the link signal-to-noise ratio and the maximum transmission power of the nodes.

[0007] Optionally, the specific process of step 1 in this invention is as follows: Step 101: Initialize the total channel resource block usage for each link; Step 102: To maximize the fulfillment of the transmission requirements of each link, select the links for which resource blocks are added; Step 103: Add a resource block to the selected link; Step 104: Determine whether all channel resources have been allocated. If yes, proceed to step 2; otherwise, return to step 102.

[0008] Optionally, step 102 of the present invention specifically includes: The link selected to increase the number of link resource blocks occupied (i) ,j )for:

[0009] in, For a set of network nodes, Add a resource block gain function to link (i,j). This represents the total amount of resource blocks used in link (i,j); Optionally, the present invention described Defined as: in,

[0010] in, It is the transmission rate that a link can achieve by occupying a resource block. The communication requirements of link (i,j).

[0011] Optionally, the specific process of step 2 in this invention is as follows: Step 201: Initialize the number of remaining sub-bands in each time slot to the total number of bands; Step 202: Sort all links in descending order of total channel resource usage to obtain the link sorting queue. ; Step 203: Retrieve the link sorting queue The first link in the chain is denoted as link (i). ,j ); Step 204: Calculate the number of resource blocks allocated this time:

[0012] in, For link (i ,j Total resource block usage Number of remaining sub-bands in time slot n; Step 205: Calculate the set of available time slots allocated this time:

[0013] Step 206: From the set of available time slots The current link (i) is selected. ,j The allocated time slot n Update link (i) ,j In time slot n Number of frequency bands allocated and the number of remaining unallocated resource blocks ,like If the value is 0, then link (i) will be... ,j From the link sorting queue Remove, otherwise, link (i) ,j Move to the link sorting queue end; Step 207: If the link sorting queue If the set is empty, proceed to step 3; otherwise, return to step 204.

[0014] Optionally, the specific process of step 206 in this invention is as follows: From the set of available time slots The current link (i) is selected. ,j The allocated time slot n for:

[0015] in, For link (i ,j The number of frequency bands allocated in time slot n; Update link (i ,j In time slot n Number of frequency bands allocated:

[0016] Update (i ,j Number of remaining unallocated resource blocks:

[0017] like If the value is 0, then link (i) will be... ,j From the link sorting queue Remove, otherwise, link (i) ,j Move to the link sorting queue end.

[0018] Optionally, the specific process of step 3 in this invention is as follows: Step 301: For each link in the network, calculate the link ranging information strength under unit power; Step 302: Establish an optimization function for the global average position error bound of the network with respect to the transmit power of each link, and introduce the signal-to-noise ratio constraint of each link and time slot and the constraint of the sum of transmit power of each node and time slot based on the link ranging information strength. Step 303: Use convex optimization tools such as the interior point method to solve the convex problem obtained in step 302, and obtain the transmit power of each link in each time slot.

[0019] Optionally, in step 301 of the present invention, the link ranging information strength of the link (k,j) between node k and node j under unit power is... for:

[0020] in, The time slot with the most bandwidth occupied by link (k,j) For link (k,j) in time slot n The signal equivalent bandwidth, At the speed of light, Signal-to-noise ratio per unit power.

[0021] Optionally, the optimization function in step 302 of this invention is:

[0022] Where Y is the redundancy matrix used for semidefinite programming, and are the variables to be solved. Let Y be the trace of matrix Y, and I be the identity matrix. Let (k,j) be the transmit power of link (k,j) in time slot n. Let (k,j) be the signal-to-noise ratio per unit power in time slot n for link (k,j). The signal-to-noise ratio threshold for signal demodulation. This represents the maximum power available to a single node. For link ranging information strength The equivalent Fisher information matrix for network positioning.

[0023] Optionally, the network positioning equivalent Fisher information matrix of the present invention for:

[0024] in, For nodes k The location Fisher information matrix obtained by measuring with anchor nodes. This provides prior information about the position of node k. For nodes i and nodes j Incremental matrix of positioning information obtained from inter-coordinated measurements; and Represented as:

[0025]

[0026] in, For the set of anchor points, The direction matrix; The calculation method is as follows:

[0027] in, For nodes k and nodes j The direction vector between them.

[0028] Beneficial effects This invention optimizes the link time-frequency resources and node transmit power of an integrated communication and positioning network in stages. Specifically, firstly, to maximize the transmission needs of each link, links are allocated to each resource block sequentially. Secondly, considering that using wider bandwidth can improve the measurement accuracy between nodes, time-frequency resources are allocated in descending order of the total resource block occupancy. Finally, aiming to minimize the network's average position error bound, the transmit power of each link is optimized by constraining the link signal-to-noise ratio and the maximum transmit power of nodes. Compared to conventional channel resource allocation methods, this method jointly optimizes the network's communication and positioning performance, is insensitive to the initial values ​​of resource allocation, effectively meets the communication needs of each link, and reduces node positioning errors. Attached Figure Description

[0029] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 Flowchart of a method for allocating channel resources in an integrated communication and positioning network. Detailed Implementation

[0031] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0032] It should be noted that, in the absence of conflict, the following embodiments and features can be combined with each other; and, based on the embodiments of this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0033] It should be noted that various aspects of embodiments within the scope of the appended claims are described below. It will be apparent that the aspects described herein can be embodied in a wide variety of forms, and any particular structure and / or function described herein is merely illustrative. Based on this disclosure, those skilled in the art will understand that one aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number of aspects set forth herein can be used to implement the device and / or practice the method. Additionally, this device and / or method can be implemented using structures and / or functionalities other than one or more of the aspects set forth herein.

[0034] The design concept of this invention is as follows: Given the prior spatial distribution information between nodes and the transmission requirements between nodes, firstly, based on maximizing the satisfaction of the transmission requirements of each link, the corresponding links are allocated to each resource block in sequence; secondly, considering that using wider bandwidth can improve the measurement accuracy between nodes, the specific time-frequency resources are allocated in descending order of the total occupancy of the link resource blocks; finally, with the goal of minimizing the network average position error bound, the transmission power of each link is optimized by constraining the link signal-to-noise ratio and the maximum transmission power of the nodes.

[0035] Without loss of generality, the integrated communication and positioning network is described as follows: Assume there are K nodes in the network. Nodes transmit information and perform measurements with each other using wireless signals, and utilize external communication channels... Cooperative localization is achieved using anchor points with known locations. Communication between nodes and anchor points utilizes fixed channel resources. k and anchor nodej Links between ( k , j Its ranging information strength is The network uses a multi-frequency time-division multiple access (TDMA) method for resource access. Each superframe is divided into... N Each time slot and M Each sub-band, and each time slot and sub-band constitute a resource block. For a node... k With nodes i Links between ( k , i The communication requirement within a single superframe is... ,node k and nodes i The direction vector between them is ,node k and anchor node j The direction vector between them is .

[0036] Before the start of each superframe, the number of bandwidths and transmit power for each time slot are allocated to each link between nodes, such as... Figure 1 As shown, the specific steps are as follows: Step 1: Assign a link to each resource block Step 101: Initialize the total channel resource block occupancy of each link to 0. Taking the link (k,i) between node k and node i as an example, its initial total resource block occupancy is: .

[0037] Step 102: Determine which link, in turn, will most effectively reduce unmet transmission demands by increasing the number of resource blocks. The link whose resource block usage is increased (i...) ,j )for:

[0038] in, For a set of network nodes, The gain function for adding a resource block to link (i,j) is defined as: in,

[0039] in, It is the transmission rate that a link can achieve by occupying a resource block.

[0040] Step 103: For the link (i) selected in step 102 ,j Add a resource block, that is:

[0041] Step 104: Determine whether all channel resources have been allocated. If yes, proceed to step 2; otherwise, return to step 102.

[0042] Step 2: Based on the total channel resource block occupancy determined in Step 1, allocate the number of frequency bands for each time slot to each link. Step 201: Initialize the number of remaining sub-bands in each time slot to the total number of bands. Taking time slot n as an example, the number of remaining sub-bands is initialized to... Initialize the number of sub-bands occupied by each link and each time slot to 0. Taking the link (k,i) between node k and node i as an example, the number of sub-bands occupied by its time slot n is... .

[0043] Step 202: Sort all links in descending order of total channel resource usage to obtain the link sorting queue. .

[0044] Step 203: Retrieve the link sorting queue The first link in the chain is denoted as link (i). ,j ).

[0045] Step 204: Calculate the number of resource blocks allocated this time:

[0046] Step 205: Calculate the set of available time slots allocated this time:

[0047] Step 206: To enhance communication performance between nodes, the node calculates the link (i) for this step. ,j The allocated time slot n for:

[0048] Update link (i ,j In time slot n Number of frequency bands allocated:

[0049] Update (i ,j Number of remaining unallocated resource blocks:

[0050] like If the value is 0, then link (i) will be... ,j From the link sorting queue Remove. Otherwise, remove the link (i). ,j Move to the link sorting queue end.

[0051] Step 207: If the link sorting queue If the set is empty, proceed to step 3; otherwise, return to step 204.

[0052] Step 3: Based on the time-frequency resource allocation results of each link in Step 2, calculate the transmission power of each node in each time slot. Step 301: For each link in the network, calculate the link ranging information strength under unit power. Taking the link (k,j) between node k and node j as an example, the link ranging information strength under unit power is:

[0053]

[0054]

[0055] in, Let n be the number of sub-bands occupied by the time slot n of the link (k,j) between node k and node j. The time slot with the most bandwidth occupied by link (k,j) For link (k,j) in time slot n The signal equivalent bandwidth, At the speed of light, The bandwidth corresponding to a resource block. The signal-to-noise ratio per unit power is calculated as follows:

[0056] in, Let (k,j) be the link gain. This represents the noise power of the node receiver.

[0057] Step 302: Establish an optimization function for the network's global average position error bound with respect to the transmit power of each link. This optimization function transforms the problem of minimizing the network's global average position error bound into a semi-positive definite programming problem. It ensures that nodes can transmit data normally according to the channel resources agreed upon in Step 2 by introducing signal-to-noise ratio constraints for each link and time slot, and by introducing a constraint on the sum of transmit power of each node in each time slot to ensure that each node can transmit signals at the given maximum power in each time slot. The optimization problem is modeled as follows:

[0058] Where Y is the redundancy matrix used for semidefinite programming, and are the variables to be solved. Let Y be the trace of matrix Y, and I be the identity matrix. Let (k,j) be the transmit power of link (k,j) in time slot n. Let (k,j) be the signal-to-noise ratio per unit power in time slot n for link (k,j). The signal-to-noise ratio threshold for signal demodulation. This represents the maximum power available to a single node. The equivalent Fisher information matrix for network positioning is calculated as follows:

[0059] in, For nodes k The location Fisher information matrix obtained by measuring with anchor nodes. This provides prior information about the position of node k. For nodes i and nodes j The incremental matrix of positioning information obtained from inter-coordinated measurements can be represented as follows:

[0060]

[0061] in, For the set of anchor points, The direction matrix; The calculation method is as follows:

[0062] in, For nodes k and nodes j The direction vector between them.

[0063] Step 303: Use convex optimization tools such as the interior point method to solve the convex problem obtained in step 302, and obtain the transmit power of each link in each time slot.

[0064] By utilizing the time-frequency resource allocation results obtained in step 2 and the transmission power allocation results obtained in step 3, each node in the network can improve the collaborative positioning accuracy while maintaining high-speed communication.

[0065] In summary, the above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for allocating channel resources in a communication and positioning integrated network, characterized in that, The specific process is as follows: Step 1: Based on maximizing the transmission requirements of each link, allocate the corresponding link to each resource block in turn; Step 2: Allocate the specific time-frequency resources in descending order of the total total resource block usage of the link; Step 3: With the goal of minimizing the network average location error bound, optimize the transmission power of each link by constraining the link signal-to-noise ratio and the maximum transmission power of the nodes.

2. The communication and positioning integrated network channel resource allocation method according to claim 1, characterized in that, The specific process of step 1 is as follows: Step 101: Initialize the total channel resource block usage for each link; Step 102: To maximize the fulfillment of the transmission requirements of each link, select the links for which resource blocks are added; Step 103: Add a resource block to the selected link; Step 104: Determine whether all channel resources have been allocated. If yes, proceed to step 2; otherwise, return to step 102.

3. The communication and positioning integrated network channel resource allocation method according to claim 2, characterized in that, Step 102 specifically involves: The link selected to increase the number of link resource blocks occupied (i) ,j )for: in, For a set of network nodes, Add a resource block gain function to link (i,j). This represents the total amount of resource blocks occupied by link (i,j).

4. The communication and positioning integrated network channel resource allocation method according to claim 3, characterized in that, The Defined as: in, in, It is the transmission rate that a link can achieve by occupying a resource block. The communication requirements of link (i,j).

5. The communication and positioning integrated network channel resource allocation method according to claim 1, characterized in that, The specific process of step 2 is as follows: Step 201: Initialize the number of remaining sub-bands in each time slot to the total number of bands; Step 202: Sort all links in descending order of total channel resource usage to obtain the link sorting queue. ; Step 203: Retrieve the link sorting queue The first link in the chain is denoted as link (i). ,j ); Step 204: Calculate the number of resource blocks allocated this time: in, For link (i ,j Total resource block usage Number of remaining sub-bands in time slot n; Step 205: Calculate the set of available time slots allocated this time: Step 206: From the set of available time slots The current link (i) is selected. ,j The allocated time slot n Update link (i) ,j In time slot n Number of frequency bands allocated and the number of remaining unallocated resource blocks ,like If the value is 0, then link (i) will be... ,j From the link sorting queue Remove, otherwise, link (i) ,j Move to the link sorting queue end; Step 207: If the link sorting queue If the set is empty, proceed to step 3; otherwise, return to step 204.

6. The communication and positioning integrated network channel resource allocation method according to claim 5, characterized in that, The specific process of step 206 is as follows: From the set of available time slots The current link (i) is selected. ,j The allocated time slot n for: in, For link (i ,j The number of frequency bands allocated in time slot n; Update link (i ,j In time slot n Number of frequency bands allocated: Update (i ,j Number of remaining unallocated resource blocks: like If the value is 0, then link (i) will be... ,j From the link sorting queue Remove, otherwise, link (i) ,j Move to the link sorting queue end.

7. The communication and positioning integrated network channel resource allocation method according to claim 1, characterized in that, The specific process of step 3 is as follows: Step 301: For each link in the network, calculate the link ranging information strength under unit power; Step 302: Establish an optimization function for the global average position error bound of the network with respect to the transmit power of each link, and introduce the signal-to-noise ratio constraint of each link and time slot and the constraint of the sum of transmit power of each node and time slot based on the link ranging information strength. Step 303: Use convex optimization tools such as the interior point method to solve the convex problem obtained in step 302, and obtain the transmit power of each link in each time slot.

8. The communication and positioning integrated network channel resource allocation method according to claim 7, characterized in that, In step 301, the link ranging information strength between node k and node j under unit power is... for: in, The time slot with the most bandwidth occupied by link (k,j) For link (k,j) in time slot n The signal equivalent bandwidth, At the speed of light, Signal-to-noise ratio per unit power.

9. The communication and positioning integrated network channel resource allocation method according to claim 8, characterized in that, The optimization function in step 302 is: Where Y is the redundancy matrix used for semidefinite programming, and are the variables to be solved. Let Y be the trace of matrix Y, and I be the identity matrix. Let (k,j) be the transmit power of link (k,j) in time slot n. Let (k,j) be the signal-to-noise ratio per unit power in time slot n for link (k,j). The signal-to-noise ratio threshold for signal demodulation. The maximum power available to a single node. For link ranging information strength The equivalent Fisher information matrix for network positioning.

10. The communication and positioning integrated network channel resource allocation method according to claim 9, characterized in that, The network positioning equivalent Fisher information matrix for: in, For nodes k The location Fisher information matrix obtained by measuring with anchor nodes. This provides prior information about the position of node k. For nodes i and nodes j Incremental matrix of positioning information obtained from inter-coordinated measurements; and Represented as: in, For the set of anchor points, The direction matrix; For nodes k and anchor node j The direction vector between them.

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