TW201403943A - Method and system of utilizing smart antennas in establishing a backhaul network - Google Patents

Abstract

A method and system for utilizing smart antenna in transmission of messages between nodes are disclosed. A wireless communication system includes a plurality of nodes, and each node is capable of being connected to each other node. At least a portion of the nodes are provided with a smart antenna configured to generate a plurality of directional beams. Each node maintains a list of other nodes and beam configuration information to be used in transmission of messages to other nodes. When a source node is required to transmit to a target node, the source node retrieves the beam configuration information and transmits with a directional beam directed to the target node.

Description

Method and system for establishing a smartback antenna to establish a backhaul network

The present invention relates to a wireless communication, and more particularly to a method and system for using a smart antenna to establish a backhaul network.

One of the most important issues in wireless communication systems is to increase system capacity by reducing interference. Array antennas (also known as smart antennas) have been developed to improve capacity and reduce interference. Smart antennas use a plurality of antenna elements to produce a directional beam that only transmits signals to a particular orientation. With smart antennas, wireless communication systems increase capacity and reduce interference because signals are sent to a narrow area within the coverage area. Since the transmitter can increase the transmission power level of the pointing beam without causing excessive interference to other transmitters or receivers, such as WTRUs and base stations, the overall system capacity is increased.

A wireless communication system usually includes a plurality of nodes, such as a base station and a wireless network controller, etc., and the nodes are typically connected to each other in a wired manner, such as a mesh network or a cellular network, and nodes communicate with each other and transmit messages. , such as a return message.

However, the disadvantage of wired connections in establishing backhaul networks is that they are too expensive, time consuming, and inflexible or modified by the network. In particular, the mesh network must require nodes to be connected to each other. When a new node joins the mesh network, it is a heavy load (in terms of cost and time) to establish a new connection to the new node for the backhaul.

There is therefore a need for an efficient use of cost, less time consuming, and flexible methods and systems to establish a backhaul network.

The present invention is an apparatus and system for utilizing a smart antenna to establish a backhaul network. The present invention directly uses smart antennas to improve intra-cell communication, increase throughput, and form at least a portion of a flexible backhaul network to transmit backhaul data. The present invention is used in a wireless communication system including a plurality of nodes, wherein each node is connected together in a mesh network, and at least a portion of the nodes provide one or more smart antennas configured to generate a plurality of Each pointing beam, each node with one or more smart antennas maintains a table containing other nodes with smart antennas, beam directions, and configuration information for transmitting messages to other nodes. When the source node needs to transmit the backhaul data to the target node, the source node retrieves the beam direction and configuration information of the target node, and transmits the message to the pointing beam directed to the target node.

100‧‧‧Network

102a-n‧‧‧ plural nodes

109a-h‧‧ beam

110‧‧‧ core network

A-F‧‧‧ link

WTRU‧‧‧Wireless Transmission/Reception Unit

1 is a block diagram of a plurality of nodes in accordance with the present invention; FIG. 2 is a block diagram of a node for fabricating in accordance with the present invention; and FIG. 3 is a diagram showing the use of a smart antenna between nodes in accordance with the present invention. A flowchart of a program for transmitting a message; and FIG. 4 is an exemplary diagram of a beam pattern generated by a node in accordance with the present invention.

The present invention is applicable to any wireless communication system including, but not limited to, time division duplex (TDD), frequency division duplex (FDD), and time division synchronous code division multiple access (TD-SCDMA), and is equally applicable to Global System for Mobile Communications (UMTS), CDMA 2000, general CDMA, Global System for Mobile Communications (GSM), Integrated Packet Radio System (GPRS), and Enhanced Data Rate GSM Evolution (EDGE).

Hereinafter, the term "WTRU" includes, but is not limited to, a User Equipment (UE), a mobile station, a fixed or mobile subscriber unit, a pager, or any form of device operable in a wireless environment. The term "Node B" is used hereinafter to include, but is not limited to, a base station, a station controller, an access point, or any acquaintance in a wireless environment. Interface device.

Figure 1 is a block diagram of a network 100 of a plurality of nodes 102a-n in accordance with the present invention. At least one of the nodes, 102n shown, is coupled to a core network 110. The operation of the core network of a wireless communication system is well known to those skilled in the art and is not an important aspect of the present invention, so the core network 110 will not be explained in detail herein.

Each node 102a-n serves one or more WTRUs (not shown) that are located within the coverage area of the nodes 102a-n, which may be a mesh network or a cellular network. In the context of the present invention, both the mesh network and the cellular network transmit backhaul information, but the base is different. The cellular network generally has a fixed network infrastructure and a backhaul connection, and these connections are generally point-to-point connections. Without change, a node transmits backhaul data to another node in another location on the network and only to that location.

In the case of a mesh network, the links between nodes change, and therefore the backhaul data can be transmitted to different nodes in another route at different times, especially in a mesh network, since the backhaul link can be over time. It is important to change the smart antenna so that it can be connected to different nodes without excessive interference to other nodes.

At least a portion of the nodes 102a-n provide at least one smart antenna (described in more detail below) and, in addition to the general download transmission to and from the WTRUs, the smart antenna is used to transmit the backhaul data to the other nodes 102a. n, these nodes 102a-n have the ability to generate a plurality of pointing beams and direct the beam to the azimuth direction.

The network 100 is expected to include nodes with wired connections, as well as nodes using wireless backhaul connections with smart antennas, which can be reconfigured and point to different nodes since the connections established using smart antennas increase the flexibility of the system. However, at least one node will have a wired connection to the core network 110 and wirelessly to other nodes to provide a connection between the wireless node group and the substantially wired core network, at least a portion of the nodes 102a-n The ability to transmit backhaul information over a wired or private connection is also provided. Nodes with wired and wireless backhaul connections (shown as 102n, hereinafter referred to as a hybrid node) will be connected to the wired core network 110. In other words, when the node wirelessly transmits the backhaul information via the help of the smart antenna, the backhaul information will eventually be routed to the core network through the hybrid node 102n, so the hybrid node 102n can receive and send backhaul information through the wireless backhaul link. Node, which can also receive and send backhaul information to the core network Road 110, thereby forming a bridge.

In one embodiment, nodes 102a-n have a plurality of predetermined beams 109a-h as shown in FIG. 4, and one of a plurality of beams 109a-h is selected to point to a transmission or reception. The eight squares shown in Figure 4 are beams, which can be generated by each node 102a-n. It is worth noting that the beam shown in Figure 4 is just an example, any number of beams, beam patterns or any form of mode. All can be executed.

In another embodiment, each beam 109a-h can be generated and pointed at once without having to pick from a preset set of locations.

Nodes 102a-n can select beams 109a-h direction dynamically or from a plurality of valid locations, which provides optimal performance in terms of system capacity, data throughput, interference, and the like. The nodes 102a-n are typically fixed at a particular location, so once the two nodes 102a-n have set a beam 109a-h and configuration, the pointing and configuration are stored and can be used without modification. Because the wireless environment and traffic load may change over time, each node 102a-n needs to be able to provide more than one beam 109a-h to link to other nodes 102a-n, so each node 102a-n monitors receipts from other The signals of nodes 102a-n are used to determine the wireless environment and dynamically adjust the beam pointing and signal configuration to achieve system performance optimization.

One embodiment of the operation of the system is as follows: a first selection node, such as node 102a, generates a beam and directs it toward other selection nodes, such as 102b, which can be achieved by adjusting the composite weights for the antenna array elements. As is typically done by a beamforming antenna array. At the same time, node 102a measures the quality of link A to node 102b, and the quality of link A can be measured by signal noise ratio, bit or frame error rate, or other measurement quality indicator. The transmitting node 102a finds the optimal antenna beam pointing, optimal weight combination to maximize the link quality, and stores the link quality measurement and corresponding beam pointing (weight). The transmitting node 102a does these things for all neighboring nodes and stores the corresponding quality and beam information.

Any of the nodes 102a-n can be flexibly and wirelessly connected or disconnected from other nodes 102a-n by selecting one or more beams directed to the other nodes 102a-n. In FIG. 1, the first node 102a uses the pointing beam A to transmit a message to the second node 102b, and uses the pointing beam B to transmit a message to the fourth node 102d. The pointing beam A and the pointing beam B are independently controlled and can simultaneously Transmission, since each pointing beam A and pointing beam B are transmitted only in a specific direction, Therefore, it does not cause excessive interference to other nodes 102a-n or WTRUs.

Figure 2 is a block diagram of a node 202 in accordance with the present invention. The node 202 includes a smart antenna 204, a controller 206, a memory 208, and a non-essential wired link 210. The wired link 210 can be linked to the core network 110 or other nodes. The node 202 performs a signal processing algorithm to accommodate user movement, changes in the radio frequency environment, and multipath of common channel interference. A Radio Resource Management (RRM) function is executed by the controller 206 to determine how the radio resources are configured in the node 202.

The smart antenna 204 includes a plurality of antenna elements (not shown) to generate a plurality of pointing beams under the control of the controller 206, each beam acting as a wireless link between the node 202 and other nodes, as above Since the node 202 is typically fixed at a particular location, the beam pointing and configuration between the two nodes can be pre-set and stored in the memory 208. The memory 208 maintains a table containing configuration information of other nodes, beam pointers, and each of the other nodes. When the node 202 needs to transmit a message to other nodes, such as backhaul data, the controller 206 will be in the memory 208. The corresponding beam pointing and configuration information is captured, and a pointing beam is directed to a specific direction, and the beam is transmitted using the beam.

In the case of the hybrid node 102n, this procedure is followed by a wireless connection with other nodes with the help of the smart antenna 204. When the hybrid node 102n establishes a backhaul connection to the core network 110 or other nodes, no configuration information or beam selection is required because the wired link 210 is physically fixed and always provides a link between the two nodes. .

In accordance with the present invention, smart antenna 204 preferably has multiple beam capabilities in which each beam can be used independently, and a node 202 generates more than one pointing beam to simultaneously transmit backhaul data to a plurality of other nodes. Since more than one pointing beam may use the same frequency in the same coverage area, the system capacity is also substantially increased.

Several nodes with several beams can be coupled together, which makes changing connections and dynamically adapting changes in the wireless environment very common. For example, two beams may be provided between two nodes for connection. If one beam is excessively interfered, the node may switch to another beam to transmit a message.

The use of smart antennas makes the backhaul link between nodes flexible, because each node is configured to generate a plurality of pointing beams and can direct the pointing beam to any orientation. Therefore, when a new node is added to the network 100, the existing node can establish a new beam direction by simply setting a new beam direction, and establishing a link to the new node for the new node, in addition, when When the existing node is removed by the network 100, the node can also easily delete the beam pointing and configuration information of the removed node by the memory 208. The present invention enables the establishment or removal of links between nodes without the need for additional setup or deletion of devices, notably the present invention can be implemented in a mesh network or a cellular network.

One of the strengths of mesh networks is their ability to generate new links and remove other links between nodes, relying on a number of factors, including traffic load, interference, and individual node performance. As shown in Fig. 1, a plurality of nodes 102a-n are coupled to each other using smart antennas. The line between nodes 102a-n in Fig. 1 indicates possible links AF, and control can be concentrated, whereby at least one node acts as The control node controls the connections between the nodes, and the control can also be dispersed, whereby the control can be distributed over several nodes or all nodes. If a node is designated as a control node, the control node collects information about the traffic status and the performance of each node, and determines the traffic route that is optimally transmitted by one node to another.

Each node 102a-n preferably transmits one or more beacon signals in one or more of its beams, which provides information useful for the operation of the network. For example, the beacon signal can transmit current power levels, traffic levels, interference levels, and other parameters. Beacon signals may also include access, priority, security, identification, and other forms of access control and security control information. The beacon signal is a periodic or aperiodic measurement and is used as a basis for adjusting the inter-node connections to find the most efficient flow path. The use of a smart antenna to form at least a portion of a wireless backhaul link in accordance with the present invention provides flexibility in establishing and adjusting connections between nodes and reduces unnecessary costs.

For example, as shown in FIG. 1, if the traffic load between the second node 102b and the fourth node 102s is too heavy, the other nodes know the two nodes 102b, 102d by reading the signal signals of the nodes 102b, 102d. The flow condition between them, which will be described below. If the first node 102a wants to queue traffic to the fifth node 102e, the second and fourth nodes 102b, 102d will be avoided, if feasible, and will be routed through the Nth node 102n.

The present invention not only has the advantage of providing a resilient, wireless mesh network, but it is now also possible to have backhaul information (typically transmitted over a wireline) via the same elastic link through the smart antenna. According to the present invention, the form of the dual-use smart antenna mechanism is also significantly improved. The advantages of current wireless communication systems.

Figure 3 is a flow chart showing a procedure 300 for transmitting inter-node messages using a smart antenna in accordance with the present invention. At least a portion of the nodes provide at least one smart antenna configured to generate a plurality of pointing beams and then independently direct the orientation (step 302). Each beam is used as a wireless link to other nodes in addition to the traffic typically downloaded to the WTRUs and the traffic uploaded by the WTRUs. Each node maintains a table containing other nodes and beam pointing and configuration information for transmission to other nodes (step 304). It must be noted that steps 320 and 304 are typically performed according to a set system or a reconfiguration system to perform actions to accept or delete nodes, and typically will not need to be formed under normal operation. When a source node needs to transmit to the target node, the source node retrieves the beam pointing and configuration information of the target node from the memory, and uses the beam pointing and configuration information to generate a pointing beam (step 306). Once a node is selected for transmission of backhaul data, based on link quality and other considerations such as traffic density, the transmitting node selects the beam pointing (weight) from the table and will use it on the antenna.

Because the environment may change, procedures for measuring link quality and storing relevant information may require periodic execution, and beam pointing adjustments are also necessary. The source node then transmits to the target node with the generated directed beam (step 308).

In a non-essential step, network changes may occur, whereby a new node may be added to the network, an existing node may be removed from the network, or the wireless frequency or other status may have Changed. In response to these changes, other nodes will update the beam pointing and configuration information tables that reflect these changes (step 310).

Although the features and elements of the present invention are described in a particular combination of the embodiments, each feature or element of the embodiments can be used alone, without being combined with other features or elements, and/or without the present invention. Other features and components are combined differently.

Claims (27)

Using at least one smart antenna to establish a wireless communication method for a backhaul network, the wireless communication method includes: a plurality of nodes, each node being coupled to at least one neighboring node, each node comprising: a smart antenna configured to generate a plurality of a pointing beam; a memory configured to store a table having connected neighboring nodes, and beam configuration information for transmitting information to the neighboring node; and a controller configured to: monitor from Selecting a signal received by the neighboring node and determining a configuration for transmitting the data to the neighboring node to update the table stored in the memory, and selecting the specific one using the updated table stored in the memory The pointing beam transmits a specific message to another node, and at least one of the plurality of nodes is a hybrid node, and the hybrid node further includes a wired backhaul link to a core network. The system of claim 1, wherein the hybrid node of claim 1 further comprises a wired backhaul link to at least one of the neighboring nodes. The system of claim 1, wherein the plurality of generated beam systems are selected from a predetermined set of locations. The system of claim 1, wherein the plurality of generated beam systems are dynamically selected and immediately directed. The system of claim 1, wherein the pointing beam is configured to provide optimal performance in terms of system capacity, data throughput, and interference. The system of claim 1, wherein at least a portion of the node is configured to transmit backhaul information over the wired backhaul link. The system of claim 1, wherein the hybrid node is configured to receive and transmit backhaul information to another node by using a wireless backhaul link when the hybrid node receives and transmits backhaul information to the core network. . The system of claim 1, wherein the plurality of nodes comprise a mesh network. The system of claim 1, wherein the plurality of nodes comprise a cellular network. A wireless communication node for use in a wireless communication system, comprising: a smart antenna configured to generate a plurality of pointing beams; a memory configured to store a table of neighboring nodes and a message for use in the neighboring node Transmitted beam configuration information; and a controller configured to: update the memory stored in the memory by monitoring signals received from the neighboring node and determining an optimum configuration for transmitting data to the neighboring node The table, and the updated table stored in the memory, is used to select a particular pointing beam for transmitting a particular message to another node for establishing a backhaul network. The wireless communication node described in claim 10 of the patent application further includes a wired backhaul link to one of the core networks. The wireless communication node of claim 11, wherein when the node receives and transmits backhaul information to the core network, the node is configured to receive and transmit backhaul information to another node by using a wireless backhaul link. . The wireless communication node according to claim 10, further comprising a wired backhaul link to one of the at least one other node. The wireless communication node of claim 10, wherein the generated plurality of pointing beams are selected from a predetermined set of locations. The wireless communication node of claim 10, wherein the plurality of generated beam systems are dynamically selected and immediately directed. The wireless communication node of claim 15, wherein the pointing beam is selected to provide optimal performance in terms of system capacity, data throughput, and interference. The wireless communication node of claim 10, wherein the node is configured to transmit backhaul information through the wired backhaul link. The wireless communication node as described in claim 10 is configured for a wireless mesh network. The wireless communication node as described in claim 10 is configured for a cellular network. A method of using a smart antenna in a wireless communication system, the wireless communication system comprising a plurality of nodes, each of the at least two of the plurality of nodes having a smart antenna to generate at least one for linking to at least one neighboring node a pointing beam, the method comprising: each node transmitting a beacon signal with a beacon message to a neighboring node, wherein the beacon message includes configuration information; measuring and storing a neighboring node having a link and a beam direction And a configuration information for transmitting the message to the neighboring node; generating, according to the beam direction and the configuration information, transmitting a specific message to one of the target nodes to point to the beam; and generating the directed beam, Transfer the message to the target node. The method of claim 20, wherein each node is coupled by using more than one beam, whereby a beam is adaptively switched between the provided beams for the link. The method of claim 20, further comprising the step of updating the table reflecting changes or modifications of the network. The method of claim 20, further comprising obtaining information about the traffic load condition and the performance of the neighboring node, and the step of selecting an appropriate path for transmitting the message to another node based on the information. The wireless communication node of claim 20, wherein the plurality of nodes comprise a mesh network. The wireless communication node of claim 20, wherein the plurality of nodes comprise a cellular network. The wireless communication node of claim 20, wherein one of the plurality of nodes is assigned as a control node, and the control node collects information and control about traffic load conditions and performance of neighboring nodes. The path of the node is determined. A wireless communication node as claimed in claim 20, wherein each node uses the beacon message to select an appropriate path for transmitting a message to one of the other nodes.