CN103634246A - A method based on a TDMA for eliminating interferences among heterogeneous fusion network clusters - Google Patents

Abstract

The present invention provides a method for eliminating interference between clusters in a TDMA-based heterogeneous fusion network. The method includes: assigning TDMA frames to clusters in a wireless sensor network according to a TDMA allocation table; the TDMA allocation table includes a cluster head identity, including TDMA frame with start time and duration, overlapping subframes allocated to nodes in overlapping regions between clusters; overlapping subframes are a period of duration in a TDMA frame. The present invention uses the TDMA mechanism of time slot allocation to eliminate the inter-cluster interference of the sensor network through the assistance of the base station, reduces energy loss and unnecessary signaling interaction in routing reconstruction, avoids energy consumption caused by retransmission, and reduces It reduces the packet loss rate, signaling overhead and delay, improves the throughput of the network system, prolongs the life cycle of the WSN network, and improves energy efficiency.

Description

A TDMA-based Intercluster Interference Elimination Method for Heterogeneous Converged Networks

technical field

The invention belongs to the technical field of wireless communication, and relates to an interference elimination method, in particular to a TDMA-based heterogeneous fusion network inter-cluster interference elimination method.

Background technique

Since the middle of the 20th century, the combination of computing technology and network technology has given birth to many new application models and technical means, but the combination of the two still basically falls within the category of traditional "human-human" or "human-computer" interaction. Until the 1990s, with the rapid development of communication technology, embedded computing technology and microelectronics technology, when the manufacturing cost of various electronic products continued to decrease to an acceptable range, a kind of sensor with perception, calculation and Communication capabilities, and can be applied to a variety of micro-smart sensors in different environments began to appear around the world. The networking of these tiny sensor nodes has completely changed the way people obtain information, which is wireless sensor network technology. Wireless sensor network is an emerging network technology with great development potential. This kind of network can randomly deploy a large number of simple nodes in a harsh environment with great redundancy. Through self-organized networking between nodes, it can Collaboratively monitor, perceive and collect information of various complex environments or monitoring objects in the network distribution area in real time, and process the information in the network, so as to obtain detailed and accurate information and transmit it to the background backbone network server or relevant observers .

One of the key issues in wireless sensor networks is the design of media access control, because a large amount of node energy is consumed in media access control. Although the media access control mechanism of time division multiple access essentially solves the collision problem, it has poor scalability. The tree-based TDM access mechanism is more scalable than the traditional TDM access mechanism, but it will introduce interference problems when there are overlapping areas between clusters in the same area.

There are many methods for solving interference at present, one method is CSMA access method based on contention, time slot allocation method and frequency hopping method based on TDMA, and so on. A relatively simple and effective method is to use collision detection multiple access or frequency division multiplexing LEACH and HEED for inter-cluster communication, and use an independent time division multiplexing access mechanism in each cluster. Although this method can effectively reduce interference, it increases spectrum usage cost and complexity of network interface.

The second method is that each cluster maintains a local time-division multiplexed media access control frame. In order to avoid time slot allocation overlap with other nodes in the neighbor cluster overlap area, the node first performs carrier sense to determine whether data is being transmitted in the channel, and if the channel is idle, data is transmitted, otherwise the data packet is buffered until the next allocated time slot. However, this method of detecting the carrier by the member nodes in the cluster will cause a lot of energy consumption.

The third method is shown in Figure 1 and Figure 2. This method defines two different types of sensor nodes according to the location information of the sensor network nodes: the first type of sensor nodes are nodes in non-overlapping areas between clusters, using The time-division multiplexing mechanism communicates with the cluster head; the second type of sensor node is a node in the overlapping area between clusters, and uses a contention-based media access mechanism to communicate with the cluster head. Therefore, its detailed process can also be divided into two parts: inter-cluster scheduling and network-wide signaling transmission. This method defines the following relevant parameters:

CH: cluster head node, that is, select the appropriate sensor node as the cluster head according to different cluster selection methods;

GW: Nodes within one hop range of two or more nodes selected according to a certain algorithm;

BS: A node that connects to the backbone network in a wired manner and manages the wireless sensor network;

TN: In the non-overlapping area, use the TDMA method to perform medium access and communicate with the cluster head;

CN: In the overlapping area, use the CSMA method to perform medium access and communicate with the cluster head;

BTP: during the beacon transmission period used for downlink transmission between the base station and the cluster head;

BRP: Beacon forwarding period for gateway downlink transmission.

The details of the intra-cluster scheduling process are as follows:

1) The cluster head node sends beacons and queries to the nodes in the overlapping area and the nodes in the non-overlapping area through the gateway. The cluster head node notifies the nodes in the non-overlapping area of the time-division multiplexing time slots according to the time-slot allocation information of the nodes in each non-overlapping area in the time-division multiplexing subframe.

2) The nodes in the non-overlapping area adopt the medium access mechanism of time division multiplexing to communicate with the cluster head node in the time division multiplexing subframe.

3) During beacon forwarding, the gateway forwards the beacons and queries received from the cluster-head nodes to neighboring cluster-head nodes. The beacon forwarding period is used for the gateway's downlink transmissions.

4) The nodes in the overlapping area use the contention-based (CSMA/CA) media access method to communicate with the cluster head node.

The signaling transmission of the base station assisting cluster scheduling is as follows:

1) The base station connected to the backbone network in a wired manner and manages the wireless sensor network sends beacons and query requests to all gateways, non-overlapping area nodes and overlapping area nodes in the same cluster.

2) After receiving the beacon and query request from the base station, the intra-cluster gateway forwards it to the neighboring cluster head node.

3) After receiving the beacon and query from the gateway, the neighbor cluster head node sends it to all gateways, overlapping area nodes and non-overlapping area nodes in its cluster during the beacon transmission of the second frame.

4) After receiving the beacon and query from the cluster head node, these gateways send it to its neighbor cluster head nodes during the beacon forwarding of the second frame.

The above process is repeated until all nodes in the sensor network receive the beacon and query request sent by the base station, as shown in Figure 3. The frame format of the subframe in the above solution is shown in FIG. 4 . In this traditional method for solving interference, the nodes in the overlapping area adopt the medium access method of CSMA/CA, which can eliminate part of the inter-cluster interference. However, when the sensor network is widely distributed and dense or a certain cluster is far away from the base station, the signaling process will be very long. Because the base station needs to periodically send beacons and queries to schedule nodes in the entire network, while the cluster head nodes and gateways need to continuously send and forward beacons and queries, it will cause a lot of signaling overhead and energy consumption; on the other hand, When there are a large number of nodes in the overlapping area, this method cannot effectively avoid packet collisions. The above three methods cannot solve the interference problem between sensor network clusters very well. Therefore, how to use cellular resources to solve the inter-cluster interference based on the TDMA mechanism in the tree topology sensor network A key issue in network convergence.

Contents of the invention

In view of the shortcomings of the prior art described above, the purpose of the present invention is to provide a method for eliminating inter-cluster interference in a TDMA-based heterogeneous fusion network, which is used to solve the problem of inter-cluster interference based on the TDMA mechanism in the existing wireless sensor network .

To achieve the above object and other related objects, the present invention provides a TDMA-based method for eliminating inter-cluster interference in a heterogeneous converged network.

A method for eliminating interference between clusters in a TDMA-based heterogeneous fusion network, the method comprising: assigning TDMA frames to clusters in a wireless sensor network according to a TDMA allocation table; the TDMA allocation table includes a cluster head identity, including a start time and duration TDMA frames, overlapping subframes allocated to nodes in overlapping regions between clusters; overlapping subframes are a period of duration in the TDMA frame.

Preferably, the TDMA allocation table is maintained by the base station.

Preferably, when the base station cannot distinguish whether a node is in an inter-cluster overlapping area, the implementation process of the TDMA-based heterogeneous fusion network inter-cluster interference elimination method is as follows:

S11, when the member nodes in the cluster have data to send to the cluster head node, the cluster head node sends a TDMA frame request to the mobile gateway;

S12. After receiving the TDMA frame request, the mobile gateway sends a TDMA frame allocation request to the base station through the cellular network link;

S13, the base station judges whether the cluster where the cluster head node is located has an overlapping area with other clusters, if there is an overlapping area, allocate a TDMA frame completely different from the overlapping cluster to the cluster head node according to the TDMA allocation table; otherwise, the base station randomly assigning a TDMA frame to the cluster head node;

S14, the base station sends the TDMA allocation information of the cluster head node to the mobile gateway; the TDMA allocation information includes the TDMA frame allocated to the cluster head node and the identity information of the cluster head node;

S15, the mobile gateway sends the TDMA allocation information to the cluster head node through the wireless sensor network interface;

S16. The cluster head node schedules member nodes according to the TDMA frame allocated by the base station.

Preferably, when the base station can distinguish whether a node is in an inter-cluster overlapping area, the implementation process of the TDMA-based heterogeneous fusion network inter-cluster interference elimination method is as follows:

S21, when the member nodes in the cluster have data to send to the cluster head node, the cluster head node sends a TDMA frame request to the mobile gateway;

S22. After receiving the TDMA frame request, the mobile gateway sends a TDMA frame allocation request to the base station through the cellular network link;

S23. The base station judges whether the cluster where the cluster head node is located has an overlapping area with other clusters. If there is an overlapping area, the base station determines whether the member nodes in the cluster under the cluster head node are in the overlapping area; The node is in the overlapping area, then the base station distributes a TDMA frame to the cluster head node, and the overlapping subframe of the TDMA frame is different from the overlapping subframe of the TDMA frame used by the cluster with the overlapping area of the cluster where the cluster head node is located;

S24, the base station sends the TDMA allocation information of the cluster head node to the mobile gateway; the TDMA allocation information includes the TDMA frame allocated to the cluster head node and the identity information of the cluster head node;

S25, the mobile gateway sends the TDMA allocation information to the cluster head node through the wireless sensor network interface;

S26. The cluster head node schedules member nodes according to the TDMA frame allocated by the base station.

Preferably, said TDMA allocation table is maintained by a gateway.

Preferably, when the gateway cannot distinguish whether a node is in an overlapping area between clusters, the gateway allocates different TDMA frames for clusters with overlapping areas.

Preferably, when the gateway can distinguish whether a node is in an inter-cluster overlap area, the gateway allocates the same TDMA frame to the clusters with the overlap area, but allocates different overlapping subframes to the nodes in the inter-cluster overlap area.

As mentioned above, the TDMA-based heterogeneous fusion network inter-cluster interference elimination method of the present invention has the following beneficial effects:

The present invention uses the TDMA mechanism of time slot allocation to eliminate the inter-cluster interference of the sensor network through the assistance of the base station, reduces energy loss and unnecessary signaling interaction in routing reconstruction, avoids energy consumption caused by retransmission, and reduces It reduces the packet loss rate, signaling overhead and delay, improves the throughput of the network system, prolongs the life cycle of the WSN network, and improves energy efficiency.

Description of drawings

Fig. 1 shows a schematic diagram of a cluster overlapping scenario in a typical wireless sensor network.

Fig. 2 is a schematic diagram showing the process of node application processing in the cluster overlapping part in the wireless sensor network.

Fig. 3 shows a schematic diagram of an inter-cluster interference scenario in a cluster overlapping part in a wireless sensor network.

Figure 4 shows a schematic diagram of the format of the frame structure.

Fig. 5 is a schematic diagram of an application scenario of the present invention.

FIG. 6 is a schematic flowchart of a method for eliminating interference between clusters in a TDMA-based heterogeneous converged network according to the first embodiment.

FIG. 7 is a schematic flow chart of the TDMA-based method for eliminating inter-cluster interference in a heterogeneous converged network described in the second embodiment.

Detailed ways

Embodiments of the present invention are described below through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation modes, and various modifications or changes can be made to the details in this specification based on different viewpoints and applications without departing from the spirit of the present invention.

Please refer to attached picture. It should be noted that the diagrams provided in this embodiment are only schematically illustrating the basic idea of the present invention, and only the components related to the present invention are shown in the diagrams rather than the number, shape and shape of the components in actual implementation. Dimensional drawing, the type, quantity and proportion of each component can be changed arbitrarily during actual implementation, and the component layout type may also be more complicated.

The invention discloses a method for eliminating interference between heterogeneous fusion network clusters based on Time Division Multiple Access (TDMA), wherein the heterogeneous fusion network is composed of wireless sensor networks and cellular networks (Wireless SensorNetworks, WSNs) The utility model is formed by fusion and belongs to the technical field of wireless communication. The method described in the present invention can be applied to the wireless sensor self-organizing network system, and the sensor node sends the detected data to the background through the mobile phone network (including mobile network, China Unicom network, 2G/3G network, WiFi network, etc.) The server, wherein the mobile phone is a dual-mode sensor network communication module and a cellular network communication module; the invention can monitor, perceive and collect information of various monitoring environments and objects in real time, and can be widely used in military and civilian fields.

The premise of the application of the present invention is: under the framework of the fusion of the cellular network and the wireless sensor network heterogeneous network, the mobile terminal is monitored by the base station of the cellular network, and there is a wireless sensor network consisting of a group of wireless sensor nodes within the coverage of the cellular network. network. The cellular network mobile terminal acts as a mobile gateway and provides access to the backhaul wireless sensor nodes, that is, the mobile terminal is dual-mode and has a cellular network and a wireless sensor network interface. Assume that when the mobile gateway enters the wireless sensor network area, it can monitor or detect the channel of the wireless sensor network, and then the mobile gateway can collect the monitored data from the sensor nodes and forward them to the base station. In addition, the base station can determine the location of the node through network deployment or network node information reporting; and the base station needs to maintain the communication radius of each cluster head node, and learn whether there is an inter-cluster overlap area and duplicate nodes according to the communication radius information.

Through the integration of the cellular network and the wireless sensor network, the application service and coverage of the wireless sensor network can be expanded. An application scenario of the present invention is shown in Figure 5, in which there are 3 clusters, cluster 1 and cluster 2 have Overlapping area, cluster 2 and cluster 3 have an overlapping area, that is, sensor nodes belonging to cluster 1 and cluster 2 are arranged in the overlapping area of cluster 1 and cluster 2, and sensor nodes belonging to cluster 2 and cluster 3 are arranged in the overlapping area of cluster 2 and cluster 3 2 and cluster 3 sensor nodes. When cluster 1 nodes and cluster 2 nodes in the overlapping area use the same time slot, interference occurs and causes collisions. Therefore, how to use cellular resources to solve the inter-cluster interference based on the TDMA mechanism in the tree topology sensor network is the technical problem to be solved by the present invention.

In order to achieve the above purpose of eliminating inter-cluster interference, the main implementation process of the TDMA-based heterogeneous fusion network inter-cluster interference elimination method of the present invention is as follows: first, the base station (Base Station, BS) judges whether the sensor nodes are in overlapping Regions have different TDMA allocations to the clusters they are in. Secondly, the base station assists in implementing inter-cluster interference, which completes the TDMA scheduling of the entire network by maintaining a TDMA table of each cluster in the sensor network. The TDMA table includes three parts: cluster head identity, TDMA frame and overlapping subframe. Then, the present invention completes the information transmission between the cluster head node, the mobile gateway, and the base station by using an additional TDMA frame allocation method and signaling interaction, thereby effectively eliminating inter-cluster interference, avoiding retransmission caused by interference, and greatly saving nodes energy, reduce transmission delay, increase the throughput of the network system, and prolong the network life cycle.

The present invention will be described in detail below in conjunction with the embodiments and the accompanying drawings.

Embodiment one

This embodiment provides a method for eliminating inter-cluster interference in a TDMA-based heterogeneous converged network. The method is a method for eliminating inter-cluster interference in a converged network based on a tree-like sensor network topology and a time-division multiplexing access mechanism, wherein the base station It cannot distinguish whether a node is in the inter-cluster overlap region or not. The specific implementation process of this implementation is shown in Figure 6, including the following steps:

S11, when the member nodes in the cluster have data to send to the cluster head node, the cluster head node sends a TDMA frame request to the mobile gateway.

S12. After receiving the TDMA frame request, the mobile gateway sends a TDMA frame allocation request to the base station through the cellular network link.

S13, the base station checks the database and determines whether the cluster where the cluster head node is located has an overlapping area with other clusters; if there is an overlapping area, allocate an overlapping cluster (that is, the same as the cluster head node) according to the TDMA allocation table The cluster where the cluster head node is located has a completely different TDMA frame; otherwise, the base station randomly assigns a TDMA frame to the cluster head node.

The TDMA allocation table in this step is used to solve the intercluster interference of the overlapping region nodes, and this table includes three parts: the identity of the cluster head, including the TDMA frame of start time and duration, and the overlapping subframes assigned to the overlapping region nodes; An overlapping subframe is a period of time in a TDMA frame.

S14, the base station sends the TDMA allocation information of the cluster head node to the mobile gateway; the TDMA allocation information includes the TDMA frame allocated to the cluster head node and the identity information of the cluster head node.

S15. The mobile gateway sends the TDMA allocation information to the cluster head node through the wireless sensor network interface.

S16, the cluster head node schedules member nodes using a TDMA scheme according to the TDMA frame allocated by the base station; each member node in the cluster sends data to the cluster head node within the allocated time slot.

The present invention completes the information transmission between the cluster head node, the mobile gateway, and the base station by using an additional TDMA frame allocation method and signaling interaction, and uses different TDMA frame allocation methods for the position information of the node, especially when the node is located in In non-overlapping areas, time slot multiplexing is used to improve transmission efficiency. The present invention uses the TDMA mechanism of time slot allocation to eliminate the inter-cluster interference of the sensor network through the assistance of the base station, reduces energy loss and unnecessary signaling interaction in routing reconstruction, avoids energy consumption caused by retransmission, and reduces It reduces the packet loss rate, signaling overhead and delay, improves the throughput of the network system, prolongs the life cycle of the WSN network, and improves energy efficiency.

Embodiment two

This embodiment provides a method for eliminating inter-cluster interference in a TDMA-based heterogeneous converged network. The difference between it and Embodiment 1 is that the base station can distinguish whether a node is in an inter-cluster overlapping area. The specific implementation process of this implementation is shown in Figure 7, including the following steps:

S21. When the member nodes in the cluster have data to send to the cluster head node, the cluster head node sends a TDMA frame request to the mobile gateway.

S22. After receiving the TDMA frame request, the mobile gateway sends a TDMA frame allocation request to the base station through the cellular network link.

S23, the base station checks the database and determines whether the cluster where the cluster head node is located has an overlapping area with other clusters; if there is an overlapping area, the base station determines whether the member nodes in the cluster under the cluster head node are in the overlapping area; if The member nodes in the cluster are in the overlapping area, then the base station allocates a TDMA frame to the cluster head node, and the overlapping subframe of the TDMA frame is used with the overlapping cluster (that is, the cluster that has an overlapping area with the cluster where the cluster head node is located) The overlapping subframes of the TDMA frame are different.

In this step, nodes in different clusters and in overlapping areas are assigned different time slots by overlapping subframes, so as to ensure that nodes in overlapping areas communicate at different time points, thereby avoiding interference. When the base station can distinguish whether a node is in an overlapping area, the base station allocates TDMA frames with different time slots to nodes in the overlapping area. That is, if different TDMA frames are allocated to overlapping clusters, nodes in the overlapping area are naturally allocated to different time slots; or the same TDMA frame is allocated to overlapping clusters, but different overlapping subframes are allocated to overlapping area nodes.

S24, the base station sends the TDMA allocation information of the cluster head node to the mobile gateway; the TDMA allocation information includes the TDMA frame allocated to the cluster head node, overlapping subframes and identity information of the cluster head node.

S25. The mobile gateway sends the TDMA allocation information to the cluster head node through the wireless sensor network interface.

S26, the cluster head node uses the TDMA scheme to schedule member nodes according to the TDMA frame allocated by the base station; the time slot specified by the base station BS is allocated to the member nodes in the overlapping area, and the remaining time slots are allocated to other member nodes by the cluster head node.

Embodiment three

This embodiment provides a TDMA-based method for eliminating inter-cluster interference in a heterogeneous converged network, which is different from Embodiments 1 and 2 in that: the TDMA allocation table is maintained by a gateway.

When the gateway cannot distinguish whether a node is in an inter-cluster overlapping area, the gateway allocates different TDMA frames for clusters with overlapping areas.

When the gateway can distinguish whether a node is in the inter-cluster overlap region, the gateway allocates the same TDMA frame to the clusters with the overlap region, but assigns different overlapping subframes to the nodes in the inter-cluster overlap region.

The invention is suitable for urban hotspot areas where people are relatively concentrated, that is, areas where sensor networks and cellular networks cover relatively dense areas. In this area, there are a large number of mobile terminals that can become gateways. That is to say, the method described in the present invention is suitable for dense sensor networks, because the dense distribution of nodes will lead to overlapping between clusters, resulting in a large number of overlapping areas between clusters, and the access method based on TDMA cannot solve the problem well. Inter-cluster interference, so the TDMA-based heterogeneous fusion network inter-cluster interference elimination method provided by the present invention can well suppress and reduce inter-cluster interference, reduce energy consumption and transmission delay caused by sensor network nodes due to collisions, Very good to extend the network cycle.

To sum up, the present invention effectively overcomes various shortcomings in the prior art and has high industrial application value.

The above-mentioned embodiments only illustrate the principles and effects of the present invention, but are not intended to limit the present invention. Anyone skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those skilled in the art without departing from the spirit and technical ideas disclosed in the present invention shall still be covered by the claims of the present invention.

Claims (7)

1. an interference elimination method between the isomery UNE based on TDMA bunch, is characterized in that, between the described isomery UNE based on TDMA bunch, interference elimination method comprises: according to a TDMA allocation table, be bunch distribution T DMA frame in wireless sense network; Described TDMA allocation table comprises a bunch identity, the tdma frame that comprises initial time and lasting duration, the overlapping subframe of the overlapping region node between distributing to bunch; Overlapping subframe is one period of duration in tdma frame.

2. interference elimination method between the isomery UNE based on TDMA according to claim 1 bunch, is characterized in that: described TDMA allocation table is by base station maintenance.

3. interference elimination method between the isomery UNE based on TDMA according to claim 2 bunch, it is characterized in that: when base station can not distinguish node whether in bunch between during overlapping region, between the described isomery UNE based on TDMA bunch, the implementation procedure of interference elimination method is:

S11, when bunch in member node while having data to send to leader cluster node, leader cluster node sends tdma frame request to mobile gateway;

S12, mobile gateway receives after described tdma frame request, sends tdma frame distribute request by Cellular Networks chain road direction base station;

S13, whether what base station judged described leader cluster node place bunch there is overlapping region with other bunches, if there is overlapping region, according to TDMA allocation table give described leader cluster node distribute one with overlapping bunch of diverse tdma frame; Otherwise tdma frame of described leader cluster node Random assignment is given in base station;

S14, base station sends to mobile gateway by the TDMA assignment information of described leader cluster node; Described TDMA assignment information comprises tdma frame and the described leader cluster node identity information of distributing to described leader cluster node;

S15, mobile gateway sends to described leader cluster node by wireless sensing network interface by TDMA assignment information;

S16, described leader cluster node is according to the tdma frame scheduling member node of base station assigns.

4. interference elimination method between the isomery UNE based on TDMA according to claim 2 bunch, it is characterized in that: when base station can distinguish node whether in bunch between during overlapping region, between the described isomery UNE based on TDMA bunch, the implementation procedure of interference elimination method is:

S21, when bunch in member node while having data to send to leader cluster node, leader cluster node sends tdma frame request to mobile gateway;

S22, mobile gateway receives after described tdma frame request, sends tdma frame distribute request by Cellular Networks chain road direction base station;

S23, whether what base station judged described leader cluster node place bunch there is overlapping region with other bunches, if having that ，Ze base station, overlapping region determines that described leader cluster node has under its command bunch in member node whether in overlapping region; If member node is in overlapping region in this bunch, base station assigns is given tdma frame of described leader cluster node, and the overlapping subframe of this tdma frame is different from the overlapping subframe of the tdma frame of bunch use that bunch has overlapping region with described leader cluster node place;

S24, base station sends to mobile gateway by the TDMA assignment information of described leader cluster node; Described TDMA assignment information comprises tdma frame and the described leader cluster node identity information of distributing to described leader cluster node;

S25, mobile gateway sends to described leader cluster node by wireless sensing network interface by TDMA assignment information;

S26, described leader cluster node is according to the tdma frame scheduling member node of base station assigns.

5. interference elimination method between the isomery UNE based on TDMA according to claim 1 bunch, is characterized in that: described TDMA allocation table is safeguarded by gateway.

6. interference elimination method between the isomery UNE based on TDMA according to claim 5 bunch, is characterized in that: when gateway can not distinguish node whether in bunch between during overlapping region, gateway is the different tdma frame that bunch distributes with overlapping region.

7. interference elimination method between the isomery UNE based on TDMA according to claim 5 bunch, it is characterized in that: when gateway can distinguish node whether in bunch between during overlapping region, gateway is the identical tdma frame that bunch distributes with overlapping region, but in bunch between node in overlapping region distribute different overlapping subframes.

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