CN107135497B

CN107135497B - Hidden node discovery method, base station and terminal

Info

Publication number: CN107135497B
Application number: CN201610113721.2A
Authority: CN
Inventors: 柯颋; 侯雪颖; 刘建军; 王锐; 沈晓冬
Original assignee: China Mobile Communications Group Co Ltd
Current assignee: China Mobile Communications Group Co Ltd
Priority date: 2016-02-29
Filing date: 2016-02-29
Publication date: 2020-12-15
Anticipated expiration: 2036-02-29
Also published as: CN107135497A

Abstract

The invention discloses a hidden node discovery method, a base station and a terminal, which comprise the following steps: a base station receives a first hidden node list and/or a first active node list sent by a terminal; and the base station calculates a second hidden node list aiming at the terminal according to the first hidden node list and/or the first active node list sent by the terminal.

Description

Hidden node discovery method, base station and terminal

Technical Field

The present invention relates to wireless communication technologies, and in particular, to a hidden node discovery method, a base station, and a terminal.

Background

Referring to fig. 1, when two stations are close to each other and transmit signals simultaneously, strong interference may be caused to data communication of a terminal (UE) covering an overlapping area.

In order to solve the above problem, the licensed spectrum and the unlicensed spectrum use different processing strategies.

All sites belong to the same mobile operator on a particular licensed spectrum. The mobile operator reduces the above mentioned adverse effects by interference suppression techniques. The specific technical means comprises: reducing the overlapping coverage area of the adjacent cells by a station address optimization and power control technology; and/or improving the Interference bearing capacity of a few marginal users in the overlapping coverage area of the adjacent region by advanced Interference suppression technologies, such as Inter Cell Interference Coordination (ICIC), Enhanced Inter Cell Interference Coordination (eICIC), and the like.

On the unlicensed spectrum, since the unlicensed frequency band is open to all Radio Access Technologies (RATs) and all operators, different operators have the same right to deploy their respective RAT systems on the unlicensed frequency band, such as Wireless Fidelity (WIFI) and Long Term Evolution (LTE) of the unlicensed spectrum. Due to lack of coordination between different operators, the neighboring working nodes may be in close proximity, resulting in uncontrolled neighboring overlapping coverage areas. In order to suppress the problem of communication interference of users in coverage overlapping areas, the unlicensed spectrum requires that the operating node follows a Listen Before Talk (LBT) mechanism, that is, Before data transmission is performed each time, a period of time is reserved to sense a carrier, a Clear Channel Assessment (CCA) process is performed, and data transmission is started when the carrier is sensed to be available. Therefore, in the scenario shown in fig. 1, when two Access Points (APs) are close to each other and are within the CCA listening range of each other, the two APs occupy channel resources in a time-sharing manner through an LBT mechanism, so that adverse effects of the site overlapping coverage problem on UE communication can be effectively suppressed.

However, referring to fig. 2, when two stations are a little far away, that is, outside the CCA listening range of each other, and there is a certain overlapping coverage area between the two stations, the communication performance of the UE in the overlapping coverage area may still be greatly affected. In particular, for any station (e.g., eNB1), other stations (e.g., APs) that are outside of its CCA listening range_hiden) Referred to as hidden nodes. And vice versa.

There are two main hidden node discovery techniques.

A first hidden node discovery technique: when both the source node and the hidden node belong to the WIFI system, a Request To Send (RTS)/Clear To Send (CTS) technique is widely adopted to solve the hidden node problem.

The RTS/CTS technique principle is briefly described below. It should be noted that the RTS/CTS technology is unique to WIFI, and it is difficult to implement a mutual identification function across RAT hidden nodes (i.e., letting Licensed-Assisted Access (LAA) systems and WIFI systems identify hidden nodes of each other). Since the basis of the RTS/CTS technique is to communicate a protocol between a plurality of devices. Due to the difference of communication systems (for example, the sampling rates of LAA and WIFI devices are different, and the widths of subcarriers of Orthogonal Frequency Division Multiplexing (OFDM) modulation schemes are also different), LAA devices are difficult to detect bit (bit) information carried in WIFI signals and send signals that WIFI can demodulate; and vice versa. Therefore, the RTS/CTS technique cannot implement a mutual identification function of hiding nodes across RATs.

Fig. 3 is a schematic diagram of RTS/CTS technology. Referring to fig. 3, node 1 and node 3 are hidden nodes from each other. While node 2 and node 3 can listen to each other. Now, node 1 needs to send data to node 2.

In the RTS/CTS process flow, node 1 and node 2 need to do 4-way handshake.

Step 1: node 1 sends an RTS message.

The RTS message contains an explicit destination address, which in this example is node 2. In addition to the destination node, other nodes may also receive and demodulate the RTS message.

The RTS message includes a Network Allocation Vector (NAV) field, and the unit of the NAV field is milliseconds (ms) to indicate the duration of the channel occupation that the node 1 needs to reserve. As with fig. 4, the NAV field included in the RTS message indicates a duration covering the entire RTS/CTS interaction process, as well as the data transmission and Acknowledgement (ACK) feedback process.

When other WIFI nodes except the destination node receive the RTS message, the NAV field contained therein is demodulated, and the contention channel access opportunity is abandoned within the reserved duration indicated by the NAV field.

It should be noted that node 3 cannot receive and correctly demodulate the RTS message sent by node 1 because node 1 and node 3 are far apart.

Step 2: node 2 sends a CTS message.

Node 2 listens and demodulates the RTS message that was heard. When node 2 finds itself as the destination node, it sends a CTS message along with it.

The CTS message also contains a NAV field. The node 2 sets the NAV field in the CTS message sent by itself according to the NAV field in the RTS message. Referring to fig. 4, the NAV field included in the CTS message indicates a duration covering only the data transmission and ACK feedback process.

It should be noted that

nodes

2 and 3 are close together and can listen to each other. After node 3 listens to the CTS message sent by node 2, node 3 discards the contention channel access opportunity for the reserved duration indicated by the NAV field contained in the CTS message. I.e. node 3 will not send data during the period that node 2 receives data, node 3 will not affect the data transmission from node 1 to node 2. Namely, the CTS/RTS technique can effectively solve the hidden node problem.

And step 3: and (5) data transmission.

And 4, step 4: and (6) ACK feedback.

A second hidden node discovery technique: the hidden node discovery technology is based on the simultaneous energy detection of the transmitting end and the receiving end.

Referring to fig. 5, with respect to the eNB, a is a hidden node, B is a non-hidden node, and a and B cannot hear each other. Assuming that the eNB and the UE agree to perform channel occupancy measurement at the same time, the UE reports the measurement result to the eNB. And the eNB deduces whether the UE accessory has a hidden node or not by combining the channel occupation situation measured by the eNB side at the same time and the channel occupation situation reported by the UE.

Observation time	Transmission node	RSSI@UE	RSSI@eNB	Whether a hidden node exists on the UE side
					T1	Is free of	0	0	-
T2	A	P_A→UE	0	Y
					T3	B	P_B→UE	P_B→eNB	-
T4	A+B	P_A→UE+P_B→UE	P_B→eNB	-

TABLE 1

Table 1 is an interference signal observation table of the UE side and the eNB side, and referring to table 1, the eNB can assert that a hidden node exists on the UE side only when the UE side perceives that a channel is occupied and the eNB side does not perceive that the channel is occupied at a corresponding time. Under other conditions, for example, when the UE side and the eNB side simultaneously perceive that the channel is occupied, or the UE side and the eNB side simultaneously cannot perceive that the channel is occupied, the eNB cannot determine that the hidden node exists on the UE side.

For the scenario shown in table 1, the eNB can only assert the presence of a hidden node on the UE side if a (hidden node) transmits a signal and B (other non-hidden node) does not transmit a signal, and the UE and eNB just make channel occupancy measurements in this case.

In a congested network environment, a large number of non-hidden nodes exist in the eNB, and these non-hidden nodes and the eNB alternately occupy channel resources. There is rarely the occurrence of all hidden nodes near the eNB "silent" and non-hidden nodes near the UE just "sound".

Further, the eNB and UE probing for channel occupancy is overhead. Specifically, to reduce signaling overhead, the eNB needs to configure a periodic sounding window for the UE in advance. The period of the detection window cannot be too short, otherwise the UE needs to report the detection result frequently. Therefore, the eNB generally configures a large-period detection window for the UE, and the UE performs measurement and reporting of the channel occupancy in the detection window.

In the detection window, only when the eNB does not send data, the UE does not send data, the non-hidden node does not send data, and the hidden node has sent data, the eNB can determine whether the hidden node exists near the UE based on the UE report information. Obviously, the hidden node discovery technology based on simultaneous energy detection of the originating end and the receiving end has a low discovery probability for the hidden node due to a long probing period and too many constraints.

In summary, the existing hidden node discovery technology has the problems of insufficient universality and/or low probability of discovering hidden nodes.

Disclosure of Invention

In order to solve the above technical problem, embodiments of the present invention provide a hidden node discovery method, a base station, and a terminal.

The hidden node discovery method provided by the embodiment of the invention comprises the following steps:

a base station receives a first hidden node list and/or a first active node list sent by a terminal;

and the base station calculates a second hidden node list aiming at the terminal according to the first hidden node list and/or the first active node list sent by the terminal.

In this embodiment of the present invention, the calculating the second hidden node list for the terminal includes:

the base station builds and maintains a first non-hidden node list;

the base station calculates a second hidden node list aiming at the terminal according to the first non-hidden node list and the first hidden node list sent by the terminal; or, according to the first non-hidden node list, a first hidden node list and a first active node list sent by the terminal, calculating a second hidden node list for the terminal;

when the terminal sending information only comprises a first hidden node list, the second hidden node list is the first hidden node list; or,

when the terminal sending information only comprises a first active node list, the second hidden node list is a first active node list-a first non-hidden node list; or,

when the terminal sends information and simultaneously comprises a first hidden node list and a first active node list, the second hidden node list is the first hidden node list, the first active node list and a first non-hidden node list;

wherein in the above operation, + represents set addition, -represents set subtraction.

the base station builds and maintains a first non-hidden node list, a third hidden node list aiming at the terminal, and a third hidden node list aiming at the terminal;

the base station updates the third hidden node list into a second hidden node list according to the first non-hidden node list, a first hidden node list sent by the terminal and/or a first active node list;

when the terminal sending information only comprises the first hidden node list, the second hidden node list is a third hidden node list plus the first hidden node list; or,

when the terminal sending information only comprises a first active node list, the second hidden node list is a third hidden node list, a first active node list and a first non-hidden node list; or,

when the terminal sends information and simultaneously comprises a first hidden node list and a first active node list, the second hidden node list is a third hidden node list, a first active node list and a first non-hidden node list;

In the embodiment of the present invention, the method further includes:

the base station constructs and maintains a first potential hidden node list;

and the base station sends all or part of configuration information in the first potential hidden node list to the terminal.

In the embodiment of the present invention, the method further includes:

the base station configures a group of common channel monitoring windows for the terminal and indicates the terminal to monitor active nodes in the common channel monitoring windows; and/or the base station configures one or more groups of special channel monitoring windows for the terminal according to all or part of configuration information in a first potential hidden node list sent to the terminal, and indicates the terminal to monitor a specific potential hidden node in the special channel monitoring windows in a targeted manner.

In the embodiment of the present invention, the first and second substrates,

constructing and maintaining a first list of non-hidden nodes includes:

the base station builds and maintains a second active node list;

the base station monitors the received signal power of all or part of nodes in a second active node list;

updating a first non-hidden node list when the received power of the node is greater than or equal to a first power threshold, wherein the new first non-hidden node list is the old first non-hidden node list + the node, or,

when the receiving power of the node is less than or equal to a first power threshold and greater than or equal to a second power threshold, updating a first non-hidden node list, wherein the new first non-hidden node list is an old first non-hidden node list-the node;

In the embodiment of the present invention, constructing and maintaining the first potential hidden node list includes:

the base station builds and maintains a second active node list;

updating a first list of potential hidden nodes when the received power of the node is greater than or equal to a first power threshold, wherein the new first list of potential hidden nodes is an old first list of potential hidden nodes-the node; or,

when the receiving power of the node is less than or equal to a first power threshold and greater than or equal to a second power threshold, updating a first potential hidden node list, wherein a new first potential hidden node list is an old first potential hidden node list plus the node;

In this embodiment of the present invention, the constructing and maintaining the second active node list includes:

the base station obtains a third active node list through self detection; and/or the presence of a gas in the gas,

the base station obtains configuration information of an adjacent base station through inter-station communication, and a fourth active node list is determined according to the configuration information of the adjacent base station; and/or the presence of a gas in the gas,

the base station obtains second active node list information of an adjacent base station through inter-station communication to be used as a fifth active node list; and/or the presence of a gas in the gas,

the base station obtains a sixth active node list according to the first active node list and/or the first hidden node list sent by the terminal;

the base station updates a second active node list, wherein the new second active node list is equal to the sum of one or more node sets in an old second active node list, a third active node list, a fourth active node list, a fifth active node list and a sixth active node list;

in the above operation, + represents set addition.

In the embodiment of the present invention, the method further includes:

the base station periodically and/or aperiodically updates one or more of a second active node list, a first potential hidden node list, a first non-hidden node list and a second hidden node list;

the triggering conditions of the aperiodic update comprise: and the base station updates one or more of a first hidden node list sent by the terminal, a first active node list sent by the terminal, a second active node list sent by an adjacent base station and an associated node list, wherein the first hidden node list, the first active node list, the second active node list and the associated node list are received by the base station at random.

In this embodiment of the present invention, the configuration information included in the node list includes:

when the active node is a site of the same operator and/or a different LAA operator, the configuration information includes: one or more of a same/different operator tag, an operator identity, a cell identity (cell ID), and common reference signal configuration information; or,

when the active node is a wireless fidelity access point (WIFI AP), the configuration information includes: one or more of device identification information, and beacon frame configuration information; wherein, the beacon frame configuration information may optionally include a beacon frame period, and/or optionally include intra-period start offset information; or,

when the active node is a wireless fidelity station (WIFI STA), the configuration information includes: device identification information.

In the embodiment of the present invention, the method further includes:

the base station transmits the configuration Information to the terminal through one or more of a Downlink Control Information (DCI) signaling and a Radio Resource Control (RRC) signaling.

Another embodiment of the present invention provides a hidden node discovery method, including:

the terminal sends a first hidden node list and/or a first active node list discovered by the terminal to the base station.

In this embodiment of the present invention, the discovering, by the terminal, the first hidden node list includes:

the terminal receives a potential hidden node list sent by a base station;

the terminal determines a channel monitoring window according to the received configuration information in the potential hidden node list and monitors potential hidden nodes in the channel monitoring window;

when the existence of all or part of hidden nodes in the potential hidden node list is confirmed, the terminal sends a first hidden node list to the base station.

the terminal receives a potential hidden node list and one or more groups of special channel monitoring windows sent by a base station;

the terminal monitors specific potential hidden nodes in one or more groups of dedicated channel monitoring windows in a targeted manner according to the received configuration information in the potential hidden node list;

In this embodiment of the present invention, the discovering, by the terminal, the first active node list includes:

the terminal receives a group of common channel monitoring windows sent by a base station;

the terminal monitors and discovers surrounding active nodes in the universal channel monitoring window;

when an active node is found, the terminal sends a first active node list to the base station.

The base station provided by the embodiment of the invention comprises:

the receiving unit is used for receiving a first hidden node list and/or a first active node list sent by the terminal;

and the calculating unit is used for calculating a second hidden node list aiming at the terminal according to the first hidden node list and/or the first active node list sent by the terminal.

In the embodiment of the present invention, the base station further includes:

the building unit is used for building and maintaining a first non-hidden node list;

the computing unit is further configured to compute a second hidden node list for the terminal according to the first non-hidden node list and the first hidden node list sent by the terminal; or, according to the first non-hidden node list, a first hidden node list and a first active node list sent by the terminal, calculating a second hidden node list for the terminal;

In the embodiment of the present invention, the base station further includes:

the building unit is used for building and maintaining a first non-hidden node list and a second hidden node list aiming at the terminal;

the computing unit is further configured to update the third hidden node list to a second hidden node list according to the first non-hidden node list, and the first hidden node list and/or the first active node list sent by the terminal;

In the embodiment of the present invention, the base station further includes:

the building unit is used for building and maintaining a first potential hidden node list;

a first sending unit, configured to send, by the base station, all or part of configuration information in a first potential hidden node list to the terminal.

In the embodiment of the present invention, the base station further includes:

the configuration unit is used for configuring a group of universal channel monitoring windows for the terminal and indicating the terminal to carry out active node monitoring in the universal channel monitoring windows; and/or configuring one or more groups of dedicated channel listening windows for the terminal according to all or part of configuration information in a first potential hidden node list sent to the terminal, and indicating the terminal to listen to a specific potential hidden node in the dedicated channel listening windows in a targeted manner.

In the embodiment of the present invention, the constructing unit is further configured to construct and maintain a second active node list; the base station monitors the received signal power of all or part of nodes in a second active node list; when the received power of the node is greater than or equal to a first power threshold, updating a first non-hidden node list, wherein a new first non-hidden node list is an old first non-hidden node list + the node, and/or updating a first potential hidden node list, wherein the new first potential hidden node list is an old first potential hidden node list-the node; or when the receiving power of the node is less than or equal to a first power threshold and greater than or equal to a second power threshold, updating a first potential hidden node list, wherein a new first potential hidden node list is an old first potential hidden node list + the node, and/or updating a first non-hidden node list, wherein the new first non-hidden node list is an old first non-hidden node list-the node; wherein in the above operation, + represents set addition, -represents set subtraction.

In the embodiment of the present invention, the constructing unit is further configured to obtain, by the base station through self detection, a third active node list; and/or the base station obtains configuration information of an adjacent base station through inter-station communication, and determines a fourth active node list according to the configuration information of the adjacent base station; and/or the base station obtains second active node list information of an adjacent base station through inter-station communication to be used as a fifth active node list; and/or the base station obtains a sixth active node list according to the first active node list and/or the first hidden node list sent by the terminal; and the base station updates a second active node list, wherein the new second active node list is equal to the sum of one or more node sets in the old second active node list, the third active node list, the fourth active node list, the fifth active node list and the sixth active node list.

The terminal provided by the embodiment of the invention comprises:

a second sending unit, configured to send, to the base station, the first hidden node list and/or the first active node list discovered by the terminal.

In the embodiment of the present invention, the terminal further includes:

a discovery unit, configured to receive a potential hidden node list sent by a base station; according to the received configuration information in the potential hidden node list, a channel monitoring window is determined by self, and potential hidden nodes are monitored in the channel monitoring window; when the existence of all or part of hidden nodes in the potential hidden node list is confirmed, the terminal sends a first hidden node list to the base station.

In the embodiment of the present invention, the terminal further includes:

the discovery unit is used for receiving a potential hidden node list and one or more groups of special channel monitoring windows sent by a base station; according to the received configuration information in the potential hidden node list, specific potential hidden nodes are monitored in a targeted mode in one or more groups of dedicated channel monitoring windows; when the existence of all or part of hidden nodes in the potential hidden node list is confirmed, the terminal sends a first hidden node list to the base station.

In the embodiment of the present invention, the terminal further includes:

a discovery unit, configured to receive a set of common channel monitoring windows sent by a base station; monitoring and discovering active nodes around in the universal channel monitoring window; when an active node is found, the terminal sends a first active node list to the base station.

In the technical solution of the embodiment of the present invention, the terminal sends the first hidden node list and/or the first active node list discovered by the terminal to the base station. A base station receives a first hidden node list and/or a first active node list sent by a terminal; and the base station calculates a second hidden node list aiming at the terminal according to the first hidden node list and/or the first active node list sent by the terminal. Therefore, the embodiment of the invention belongs to a hidden node discovery technology universal for LAA/WIFI; and through the assistance of the eNB, the UE can effectively discover the hidden nodes around with lower power consumption and technical implementation complexity. The embodiment of the invention is particularly suitable for application scenes deployed by the same LAA operator and application scenes coexisting by different LAA operators.

Drawings

FIG. 1 is a schematic diagram of inter-station overlap coverage;

FIG. 2 is a schematic diagram of a hidden node;

FIG. 3 is a diagram of RTS/CTS architecture;

FIG. 4 is a schematic diagram of RTS/CTS processing flow;

FIG. 5 is a schematic diagram of hidden node discovery based on simultaneous energy detection;

fig. 6 is a flowchart illustrating a hidden node discovery method according to a first embodiment of the present invention;

fig. 7 is a flowchart illustrating a hidden node discovery method according to a second embodiment of the present invention;

fig. 8 is a schematic structural diagram of a base station according to an embodiment of the present invention;

fig. 9 is a schematic structural component diagram of a terminal according to an embodiment of the present invention;

fig. 10 is a schematic diagram of each node list according to the embodiment of the present invention.

Detailed Description

So that the manner in which the features and aspects of the embodiments of the present invention can be understood in detail, a more particular description of the embodiments of the invention, briefly summarized above, may be had by reference to the embodiments, some of which are illustrated in the appended drawings.

The embodiment of the invention takes an LAA system as an example, and researches the discovery and identification technology of peripheral hidden nodes. When the interfered system is an LAA system, its hidden nodes may be from other LAA nodes (including enbs and/or UEs) deployed by the same LAA operator, LAA nodes (including enbs and/or UEs) deployed by different LAA operators, and WIFI nodes (including APs and/or STAs). Based on the above, the embodiment of the invention provides a hidden node discovery technology universal for LAA/WIFI.

Fig. 6 is a schematic flow chart of a hidden node discovery method according to an embodiment of the present invention, where the hidden node discovery method in this example is applied to a base station, and as shown in fig. 6, the hidden node discovery method includes the following steps:

step 601: and the base station receives the first hidden node list and/or the first active node list sent by the terminal.

Step 602: and the base station calculates a second hidden node list aiming at the terminal according to the first hidden node list and/or the first active node list sent by the terminal.

Referring to fig. 10, in fig. 10, 1) a diamond shape, a square shape, and a triangle all represent nodes in the eNB-side second active node list, that is, active node information grasped by the eNB in advance; wherein, the square represents a non-hidden node, the triangle represents a potential hidden node, and the diamond represents other active nodes which are not concerned about; 2) the circle represents an active node that is discovered by the UE and not known a priori by the eNB; 3) blue indicates a hidden node or an active node that a specific UE finds and reports.

A specific implementation of the embodiment of the present invention is described in detail below with reference to fig. 10.

the base station builds and maintains a first non-hidden node list;

In the embodiment of the present invention, the method further includes:

the base station constructs and maintains a first potential hidden node list;

Here, the first hidden node is a subset of the first potential hidden node.

Here, the base station (eNB) first screens the range of the potential hidden node according to the relative spatial location information of the terminal (UE) and the potential hidden node (e.g. the eNB determines the approximate location of the UE/node based on the measurement parameters such as the azimuth, RSRP, RSSI, etc. of the UE/node), so as to reduce the communication overhead and the overhead of UE detection.

The method further comprises the following steps: the base station configures a group of common channel monitoring windows for the terminal and indicates the terminal to monitor active nodes in the common channel monitoring windows; and/or the base station configures one or more groups of special channel monitoring windows for the terminal according to all or part of configuration information in a first potential hidden node list sent to the terminal, and indicates the terminal to monitor a specific potential hidden node in the special channel monitoring windows in a targeted manner.

In the embodiment of the present invention, constructing and maintaining the first non-hidden node list and the first potential hidden node list includes:

the base station builds and maintains a second active node list;

when the received power of the node is greater than or equal to a first power threshold, updating a first non-hidden node list, wherein a new first non-hidden node list is an old first non-hidden node list + the node, and/or updating a first potential hidden node list, wherein the new first potential hidden node list is an old first potential hidden node list-the node; or,

when the receiving power of the node is less than or equal to a first power threshold and greater than or equal to a second power threshold, updating a first potential hidden node list, wherein a new first potential hidden node list is an old first potential hidden node list + the node, and/or updating a first non-hidden node list, wherein the new first non-hidden node list is an old first non-hidden node list-the node;

Here, the second power threshold is smaller than the first power threshold, and the first power threshold is a CCA energy detection threshold for LBT operation, and the second power threshold is a detection threshold implemented by the manufacturer of the master device, in order to extend the listening range.

In the embodiment of the present invention, constructing and maintaining the second active node list includes:

in the above operation, + represents set addition.

Here, the second active node is a superset of all nodes, where different node importance is different.

In particular, it is not important to exclude nodes of the third type from the first list of potential hidden nodes and the first list of non-hidden nodes.

And the information exchange between the base stations is mainly the third type node. Therefore, in order to improve the processing efficiency, the second active node list should be slimmed, that is, the third type node should be periodically deleted, so as to reduce the processing overhead.

The information exchange modes between base stations comprise push and pull. The push type is that the adjacent base station broadcasts the second active node information to the surrounding base stations periodically or aperiodically (namely, triggered by the condition); by pull, it is meant that the current base station actively requests information from neighboring base stations.

In particular, for push processing, in order to reduce communication overhead, information needs to be compressed; or incremental information may be transmitted only when a change in information occurs.

In the embodiment of the present invention, the base station periodically and/or aperiodically updates one or more of the second active node list, the first potential hidden node list, the first non-hidden node list, and the second hidden node list;

The updating process of the node list comprises the following steps:

step 1: the UE feeds back a first active node list;

step 2: the eNB updates the second active node;

and step 3: the eNB updates the first non-hidden node list;

and 4, step 4: the eNB updates the second hidden node list;

and 5: the eNB updates the first list of potential hidden nodes.

when the active node is a site of the same LAA operator and/or a site of a different LAA operator, the configuration information includes: one or more of a same/different operator tag, an operator identification, a cell ID, and common reference signal configuration information; or,

when the active node is a WIFI AP, the configuration information includes: one or more of device identification information, and beacon frame configuration information; wherein, the beacon frame configuration information may optionally include a beacon frame period, and/or optionally include intra-period start offset information; or,

when the active node is a WIFI STA, the configuration information includes: device identification information.

In the embodiment of the invention, the base station sends the configuration information to the terminal through one or more of DCI signaling and RRC signaling.

In the embodiment of the present invention, the base station is assumed to be eNB 1. The eNB1 maintains a first list of non-hidden nodes, a first list of potential hidden nodes, and a second list of active nodes. Wherein the second active node list comprises the first non-hidden node list, the first potential hidden node list and some other nodes, and is a superset of all nodes. It should be noted that the importance of different nodes is different. In particular, it is not important to exclude nodes of the third type from the first list of potential hidden nodes and the first list of non-hidden nodes.

Here, the node activity level may be different on different Component Carriers (CCs). A set of node lists may be maintained for each CC on which the eNB1 operates; or in the entry of each node in the maintained node list, distinguish CC information in the embodiment of the present invention, it is assumed that the terminal is UE 1.

First, the eNB1 updates the first non-hidden node list and the first potential hidden node list according to a signal power detection method on the basis of the second active node list. The specific method comprises the following steps: eNB1 listens for its received signal power for all or some of the nodes in the second list of active nodes. When the received power of the node is greater than or equal to a first power threshold, updating a first non-hidden node list, wherein a new first non-hidden node list is an old first non-hidden node list + the node, and/or updating a first potential hidden node list, wherein the new first potential hidden node list is an old first potential hidden node list-the node; or when the receiving power of the node is less than or equal to a first power threshold and greater than or equal to a second power threshold, updating a first potential hidden node list, wherein a new first potential hidden node list is an old first potential hidden node list + the node, and/or updating a first non-hidden node list, wherein the new first non-hidden node list is an old first non-hidden node list-the node; wherein in the above operation, + represents set addition, -represents set subtraction. Here, the second power threshold is smaller than the first power threshold, and the first power threshold is a CCA energy detection threshold for LBT operation, and the second power threshold is a detection threshold implemented by the manufacturer of the master device, in order to extend the listening range.

Second, the eNB1 sends all or part of the configuration information in the first list of potential hidden nodes to the UE1 through one or more of DCI signaling and RRC signaling to assist the UE1 to monitor and discover the first list of hidden nodes according to the configuration information. By sending only partial configuration information, the eNB1 screens and reduces the range of the first potential hidden node list to be sent to the UE1 in advance according to the relative spatial location information of the UE1 and the potential hidden nodes (for example, the eNB1 determines the approximate location of the UE1 based on the measurement parameters such as the azimuth, RSRP, RSSI, and the like of the UE 1), so as to reduce the communication overhead and the overhead detected by the UE 1.

Optionally, the eNB1 may also configure the UE1 with one or more sets of dedicated channel listening windows for all or part of the configuration information in the first list of potential hidden nodes sent to the UE1, indicating that the UE1 is to listen to a particular potential hidden node within the dedicated channel listening windows.

Optionally, the eNB1 may also configure a set of common channel listening windows for all UEs, and instruct the UEs to perform active node monitoring within the common channel listening windows.

The method for the UE1 to listen to the active node or the hidden node comprises the following steps: alternatively, the UE1 decides a channel monitoring window by itself and listens for potential active or hidden nodes within the decided channel monitoring window by itself; or the UE1 listens to the active node within the received common channel listening window, and determines the channel listening window of the hidden node according to the configuration information in the received potential hidden node list; alternatively, the UE1 listens for active nodes within the received general channel listening window and listens for specific potential hidden nodes within the received set or sets of dedicated channel listening windows.

When the eNB1 discovers the active nodes, and/or when the UE1 confirms the presence of all or part of the hidden nodes in the potential list of hidden nodes, the UE1 reports its detected first list of active nodes, and/or first list of hidden nodes, to the eNB1 periodically or aperiodically. Specifically, 1) the periodic reporting means that the eNB1 configures a static or semi-static periodic reporting window for the UE1 through RRC signaling. The periodic reporting window includes information such as a period length and/or an initial offset time in a period. 2) There are two implementation forms for aperiodic reporting: aperiodic reporting mode triggered by eNB: namely, the eNB1 temporarily instructs the UE1 to complete reporting through RRC signaling and/or DCI signaling; the UE triggered aperiodic reporting mode: when the UE1 discovers a new hidden node, and/or an active node, and/or discovers a change in active node information, the UE1 requests the eNB1 to allocate UL reporting resources and then report in the UL resources allocated by the eNB 1.

Again, the eNB1 builds or updates a second hidden node list for the UE1 from the first hidden node list detected by the UE1 and/or the first active node list detected by the UE1 sent by the UE1, the first hidden node list being a subset of the second hidden node list.

Specifically, the method for constructing the second hidden node list includes: when the information sent by the UE1 includes only the first hidden node list, the second hidden node list is the first hidden node list; alternatively, when the information sent by the UE1 includes only the first active node list, the second hidden node list is the first active node list — the first non-hidden node list; or, when the UE1 sends information including both the first hidden node list and the first active node list, the second hidden node list is the first hidden node list + the first active node list-the first non-hidden node list; wherein in the above operation, + represents set addition, -represents set subtraction.

Specifically, the updating method of the second hidden node list includes: when the information sent by the UE1 includes only the first hidden node list, the second hidden node list is the third hidden node list + the first hidden node list; alternatively, when the information sent by the UE1 includes only the first active node list, the second hidden node list is the third hidden node list + the first active node list-the first non-hidden node list; alternatively, when the UE1 sends information including both the first hidden node list and the first active node list, the second hidden node list is the third hidden node list + the first active node list-the first non-hidden node list. Wherein in the above operation, + represents set addition, -represents set subtraction.

Then, the update method of the second active node list in the lower eNB1 is introduced. In particular, the new second active node list is equal to the sum of one or more node sets in the old second active node list, the third active node list, the fourth active node list, the fifth active node list and the sixth active node list. The eNB1 obtains a third active node list through self detection; and/or the eNB1 obtains configuration information of a neighboring base station through inter-station communication, and determines a fourth active node list according to the configuration information of the neighboring base station; and/or the eNB1 obtains second active node list information of the neighboring base station as a fifth active node list through inter-station communication; and/or the eNB1 receives the first active node list and/or the first hidden node list sent by all terminals, and obtains a sixth active node list.

Specifically, the information exchange modes between the base stations include push and pull. The push type is that the adjacent base station broadcasts the second active node information to the surrounding base stations periodically or aperiodically (namely, triggered by the condition); by pull, it is meant that the current base station actively requests information from neighboring base stations. In particular, for push processing, in order to reduce communication overhead, information needs to be compressed; or incremental information may be transmitted only when a change in information occurs.

Finally, some additions to the above description are made.

1) In an embodiment of the present invention, the eNB1 updates one or more of the second active node list, the first potential hidden node list, the first non-hidden node list, and the second hidden node list periodically and/or aperiodically; the triggering conditions of the aperiodic update comprise: and the base station updates one or more of a first hidden node list sent by the terminal, a first active node list sent by the terminal, a second active node list sent by an adjacent base station and an associated node list, wherein the first hidden node list, the first active node list, the second active node list and the associated node list are received by the base station at random.

2) In the embodiment of the present invention, the configuration information included in the node list where the neighboring base station eNB1 and the eNB2 interact includes:

when the active node is a site of the same LAA operator and/or a site of a different LAA operator, the configuration information includes: one or more of a co/co-carrier tag, a carrier identification, a cell ID, and common reference signal configuration information. Specifically, (1) the common reference signals comprise all or part of PSS, and/or SSS, and/or CRS, and/or CSI-RS, and/or DRS; (2) for the periodic signals such as the PSS/SSS/DRS, the configuration information includes the period length of the periodic signal and/or the offset of the start time in the period. The offset of the start time in the period may be calibrated with the time system of eNB2, in this case, eNB1 needs to measure the offset of both eNB1 and eNB2 in the time system, and calibrate the offset of the start time in the period to its own time system. Or, the start time offset in the period may be calibrated by using a time system of the eNB1, and at this time, the eNB2 is required to calibrate the obtained start time offset in the period; (3) for PSS and SSS signals, their signal sequence can be uniquely determined by the cell ID. In addition, since the transmission periods of the PSS and SSS signals are fixed and small, it is possible to choose whether to include or not include an indication of a start offset within a period in the configuration information; (4) for CRS signals, the inclusion or exclusion of frequency shift (frequency shift) indications and/or the inclusion or exclusion of antenna port indications may be selected; (5) for the CSI-RS signal, the CSI-RS pattern indication can be selected to be contained or not contained, and/or the antenna port indication can be selected to be contained or not contained; (6) for a Discovery Reference Signal (DRS), a DRS period indication may be optionally included or not included, and/or a start time offset indication within a DRS period may be optionally included or not included, and/or some other parameter configuration information in the DRS may be optionally included or not included, such as whether a CSI-RS Reference Signal is included in the DRS Signal.

Or, when the active node is a WIFI AP, the configuration information includes: one or more of device identification information (such as BSS identification (BSS ID), and/or MAC address), and beacon frame (beacon) frame configuration information; wherein, the beacon frame configuration information may optionally include a beacon frame period, and/or optionally include intra-period start offset information; or,

when the active node is a WIFI STA, the configuration information includes: device identification information (e.g., STA identification, and/or MAC address).

3) In this embodiment of the present invention, the configuration information included in the first potential hidden node list sent by the eNB1 to the UE1 includes:

when the active node is a site of the same LAA operator and/or a site of a different LAA operator, the configuration information includes: one or more of a co/co-carrier tag, a carrier identification, a cell ID, and common reference signal configuration information. Specifically, (1) the common reference signals comprise all or part of PSS, and/or SSS, and/or CRS, and/or CSI-RS, and/or DRS; (2) for the periodic signals such as the PSS/SSS/DRS, the configuration information includes the period length of the periodic signal and/or the offset of the start time in the period. Wherein the start time offset in the period is calibrated by the time system of the eNB 1; for example: assuming that the transmission period of the reference signal is P ms and the start time offset in the period is X ms, the UE expects to observe the reference signal in a subframe where (10 × SFN + subframe offset + OFDM shift + sample shift) mod P is X. Wherein SFN represents the current radio frame number, subframe offset represents the current subframe offset (0 is equal to or less than subframe offset <10) in the radio frame, OFDM shift represents the current OFDM symbol offset (0 is equal to or less than OFDM shift <1ms) in the current subframe, sample shift represents the current sampling point offset (0 is equal to or less than sample shift <1OFDM symbol length) in the current OFDM symbol, and x mod y represents x modulo y. (3) For PSS and SSS signals, it may be chosen to include or not include an indication of a start offset within a period in the configuration information. (4) For CRS signals, the inclusion or non-inclusion of a frequency shift (frequency shift) indication and/or the inclusion or non-inclusion of an antenna port indication may be selected. (5) For the CSI-RS signal, the CSI-RS pattern indication may be optionally included or not included, and/or the antenna port indication may be optionally included or not included. (6) For the DRS signal (discovery reference signal), it may be selected to include or not include a DRS period indication, and/or to include or not include a DRS period start time offset indication, and/or to include or not include some other parameter configuration information in the DRS, such as whether the DRS signal includes a CSI-RS reference signal, or not.

Fig. 7 is a schematic flowchart of a hidden node discovery method according to a second embodiment of the present invention, and as shown in fig. 7, the hidden node discovery method includes the following steps:

step 701: the terminal sends a first hidden node list and/or a first active node list discovered by the terminal to the base station.

the terminal receives a potential hidden node list sent by a base station;

The terminal discovering the first hidden node list comprises:

The terminal discovering the first active node list comprises:

Fig. 8 is a schematic structural diagram of a base station according to an embodiment of the present invention, and as shown in fig. 8, the base station includes:

a receiving unit 81, configured to receive a first hidden node list and/or a first active node list sent by a terminal;

a calculating unit 82, configured to calculate a second hidden node list for the terminal according to the first hidden node list and/or the first active node list sent by the terminal.

In an embodiment of the present invention, the base station further includes:

a constructing unit 83, configured to construct and maintain a first non-hidden node list;

the calculating unit 82 is further configured to calculate a second hidden node list for the terminal according to the first non-hidden node list and the first hidden node list sent by the terminal; or, according to the first non-hidden node list, a first hidden node list and a first active node list sent by the terminal, calculating a second hidden node list for the terminal;

In another embodiment of the present invention, the base station further includes:

a constructing unit 83 configured to construct and maintain a first non-hidden node list and a second hidden node list for the terminal;

the calculating unit 82 is further configured to update the third hidden node list to a second hidden node list according to the first non-hidden node list, and the first hidden node list and/or the first active node list sent by the terminal;

a building unit 83, configured to build and maintain a first potential hidden node list;

a first sending unit 84, configured to send all or part of the configuration information in the first potential hidden node list to the terminal by the base station.

a configuration unit 85, configured to configure a group of common channel monitoring windows for a terminal, and instruct the terminal to perform active node monitoring in the common channel monitoring windows; and/or configuring one or more groups of dedicated channel listening windows for the terminal according to all or part of configuration information in a first potential hidden node list sent to the terminal, and indicating the terminal to listen to a specific potential hidden node in the dedicated channel listening windows in a targeted manner.

The constructing unit 83 is further configured to construct and maintain a second active node list; the base station monitors the received signal power of all or part of nodes in a second active node list; when the received power of the node is greater than or equal to a first power threshold, updating a first non-hidden node list, wherein a new first non-hidden node list is an old first non-hidden node list + the node, and/or updating a first potential hidden node list, wherein the new first potential hidden node list is an old first potential hidden node list-the node; or when the receiving power of the node is less than or equal to a first power threshold and greater than or equal to a second power threshold, updating a first potential hidden node list, wherein a new first potential hidden node list is an old first potential hidden node list + the node, and/or updating a first non-hidden node list, wherein the new first non-hidden node list is an old first non-hidden node list-the node; wherein in the above operation, + represents set addition, -represents set subtraction.

The constructing unit 83 is further configured to obtain a third active node list by the base station through self detection; and/or the base station obtains configuration information of an adjacent base station through inter-station communication, and determines a fourth active node list according to the configuration information of the adjacent base station; and/or the base station obtains second active node list information of an adjacent base station through inter-station communication to be used as a fifth active node list; and/or the base station obtains a sixth active node list according to the first active node list and/or the first hidden node list sent by the terminal; and the base station updates a second active node list, wherein the new second active node list is equal to the sum of one or more node sets in the old second active node list, the third active node list, the fourth active node list, the fifth active node list and the sixth active node list.

an updating unit 86, configured to periodically and/or aperiodically update one or more of the second active node list, the first potential hidden node list, the first non-hidden node list, and the second hidden node list;

The configuration information included in the node list includes:

Those skilled in the art will understand that the implementation functions of each unit in the base station shown in fig. 8 can be understood by referring to the related description of the hidden node discovery method. The functions of the units in the base station shown in fig. 8 may be implemented by a program running on a processor, or may be implemented by specific logic circuits.

Fig. 9 is a schematic structural composition diagram of a terminal according to an embodiment of the present invention, and as shown in fig. 9, the terminal includes:

a second sending unit 91, configured to send the first hidden node list and/or the first active node list discovered by the terminal to the base station.

In an embodiment of the present invention, the terminal further includes:

a discovery unit 92, configured to receive a potential hidden node list sent by a base station; according to the received configuration information in the potential hidden node list, a channel monitoring window is determined by self, and potential hidden nodes are monitored in the channel monitoring window; when the existence of all or part of hidden nodes in the potential hidden node list is confirmed, the terminal sends a first hidden node list to the base station.

In another embodiment of the present invention, the terminal further includes:

a discovery unit 92, configured to receive a list of potential hidden nodes sent by a base station, and one or more groups of dedicated channel listening windows; according to the received configuration information in the potential hidden node list, specific potential hidden nodes are monitored in a targeted mode in one or more groups of dedicated channel monitoring windows; when the existence of all or part of hidden nodes in the potential hidden node list is confirmed, the terminal sends a first hidden node list to the base station.

In another embodiment of the present invention, the terminal further includes:

a discovery unit 92, configured to receive a set of common channel listening windows transmitted by a base station; monitoring and discovering active nodes around in the universal channel monitoring window; when an active node is found, the terminal sends a first active node list to the base station.

Those skilled in the art will understand that the implementation functions of the units in the terminal shown in fig. 9 can be understood by referring to the related description of the hidden node discovery method. The functions of the units in the terminal shown in fig. 9 may be implemented by a program running on a processor, or may be implemented by specific logic circuits.

The technical schemes described in the embodiments of the present invention can be combined arbitrarily without conflict.

In the embodiments provided in the present invention, it should be understood that the disclosed method and intelligent device may be implemented in other ways. The above-described device embodiments are merely illustrative, for example, the division of the unit is only a logical functional division, and there may be other division ways in actual implementation, such as: multiple units or components may be combined, or may be integrated into another system, or some features may be omitted, or not implemented. In addition, the coupling, direct coupling or communication connection between the components shown or discussed may be through some interfaces, and the indirect coupling or communication connection between the devices or units may be electrical, mechanical or other forms.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, that is, may be located in one place, or may be distributed on a plurality of network units; some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, all the functional units in the embodiments of the present invention may be integrated into one second processing unit, or each unit may be separately regarded as one unit, or two or more units may be integrated into one unit; the integrated unit can be realized in a form of hardware, or in a form of hardware plus a software functional unit.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention.

Claims

1. A hidden node discovery method, the method comprising:

the base station calculates a second hidden node list aiming at the terminal according to a first hidden node list and/or the first active node list sent by the terminal;

the method further comprises the following steps:

the base station constructs and maintains a first potential hidden node list;

the base station sends all or part of configuration information in a first potential hidden node list to the terminal; the first list of hidden nodes is a subset of the first list of potential hidden nodes.

2. The hidden node discovery method of claim 1, wherein said computing a second list of hidden nodes for said terminal comprises:

the base station builds and maintains a first non-hidden node list;

the base station calculates a second hidden node list aiming at the terminal according to the first non-hidden node list and the first hidden node list sent by the terminal; or, according to the first non-hidden node list, a first hidden node list sent by the terminal and a first active node list, calculating a second hidden node list for the terminal;

3. The hidden node discovery method of claim 1, wherein said computing a second list of hidden nodes for said terminal comprises:

the base station builds and maintains a first non-hidden node list and a third hidden node list aiming at the terminal;

4. The hidden node discovery method according to any of claims 1 to 3, wherein said method further comprises:

5. The hidden node discovery method of claim 4, wherein constructing and maintaining a first list of non-hidden nodes comprises:

the base station builds and maintains a second active node list;

6. The hidden node discovery method of claim 1, wherein constructing and maintaining a first list of potential hidden nodes comprises:

the base station builds and maintains a second active node list;

7. The hidden node discovery method according to claim 5 or 6, wherein said constructing and maintaining a second list of active nodes comprises:

and the base station updates a second active node list, wherein the new second active node list is equal to the sum of one or more node sets in the old second active node list, the third active node list, the fourth active node list, the fifth active node list and the sixth active node list.

8. The hidden node discovery method of claim 1, further comprising:

the base station periodically and/or aperiodically updates the following node list: a second active node list, and/or a first potential hidden node list, and/or a first non-hidden node list, and/or a second hidden node list;

9. The hidden node discovery method according to any of claims 1 to 3 or 6, wherein the configuration information included in each node list includes:

when the active node is a site of a co-authorized spectrum assisted access LAA operator and/or a different LAA operator, the configuration information includes: one or more of a same/different operator tag, an operator identifier, a cell identifier cellID, and common reference signal configuration information; or,

when the active node is a wireless fidelity (WIFI) Station (STA), the configuration information comprises: device identification information.

10. A hidden node discovery method, the method comprising:

a terminal receives all or part of configuration information in a first potential hidden node list sent by a base station;

the terminal sends a first hidden node list and/or a first active node list discovered by the terminal to a base station; the first list of hidden nodes is a subset of the first list of potential hidden nodes.

11. The hidden node discovery method according to claim 10, wherein the discovering of the first list of hidden nodes by the terminal comprises:

the terminal determines a channel monitoring window according to the received configuration information in the first potential hidden node list and monitors potential hidden nodes in the channel monitoring window;

when the existence of all or part of hidden nodes in the first potential hidden node list is confirmed, the terminal sends the first hidden node list to the base station.

12. The hidden node discovery method according to claim 10, wherein the discovering of the first list of hidden nodes by the terminal comprises:

the terminal receives one or more groups of special channel monitoring windows sent by the base station;

the terminal monitors specific potential hidden nodes in one or more groups of dedicated channel monitoring windows in a targeted manner according to the received configuration information in the first potential hidden node list;

13. The hidden node discovery method of claim 10, wherein said terminal discovering the first list of active nodes comprises:

14. A base station, characterized in that the base station comprises:

the computing unit is used for computing a second hidden node list aiming at the terminal according to the first hidden node list and/or the first active node list sent by the terminal;

a first sending unit, configured to send all or part of configuration information in the first potential hidden node list to the terminal; the first list of hidden nodes is a subset of the first list of potential hidden nodes.

15. The base station of claim 14, wherein the base station further comprises:

16. The base station of claim 14, wherein the base station further comprises:

the building unit is used for building and maintaining a first non-hidden node list and a third hidden node list aiming at the terminal;

17. The base station according to any of claims 15 to 16, wherein said constructing unit is further configured to construct and maintain a second active node list; the base station monitors the received signal power of all or part of nodes in a second active node list; when the received power of the node is greater than or equal to a first power threshold, updating a first non-hidden node list, wherein a new first non-hidden node list is an old first non-hidden node list + the node, and/or updating a first potential hidden node list, wherein the new first potential hidden node list is an old first potential hidden node list-the node; or when the receiving power of the node is less than or equal to a first power threshold and greater than or equal to a second power threshold, updating a first potential hidden node list, wherein a new first potential hidden node list is an old first potential hidden node list + the node, and/or updating a first non-hidden node list, wherein the new first non-hidden node list is an old first non-hidden node list-the node; wherein in the above operation, + represents set addition, -represents set subtraction.

18. The base station according to claim 17, wherein the constructing unit is further configured to obtain a third active node list by the base station through self detection; and/or the base station obtains configuration information of an adjacent base station through inter-station communication, and determines a fourth active node list according to the configuration information of the adjacent base station; and/or the base station obtains second active node list information of an adjacent base station through inter-station communication to be used as a fifth active node list; and/or the base station obtains a sixth active node list according to the first active node list and/or the first hidden node list sent by the terminal; and the base station updates a second active node list, wherein the new second active node list is equal to the sum of one or more node sets in the old second active node list, the third active node list, the fourth active node list, the fifth active node list and the sixth active node list.

19. A terminal, characterized in that the terminal comprises:

the discovery unit is used for receiving all or part of configuration information in a first potential hidden node list sent by a base station;

a second sending unit, configured to send, to the base station, the first hidden node list and/or the first active node list discovered by the terminal; the first list of hidden nodes is a subset of the first list of potential hidden nodes.

20. The terminal of claim 19, wherein the discovery unit is further configured to determine a channel monitoring window according to the received configuration information in the first list of potential hidden nodes, and monitor potential hidden nodes within the channel monitoring window; when the existence of all or part of hidden nodes in the first potential hidden node list is confirmed, the terminal sends the first hidden node list to the base station.

21. The terminal of claim 19, wherein the discovery unit is further configured to receive one or more sets of dedicated channel listening windows transmitted by a base station; according to the received configuration information in the first potential hidden node list, specific potential hidden nodes are monitored in a targeted mode in one or more groups of dedicated channel monitoring windows; when the existence of all or part of hidden nodes in the first potential hidden node list is confirmed, the terminal sends the first hidden node list to the base station.

22. The terminal of claim 19, wherein the discovery unit is further configured to receive a set of common channel listening windows transmitted by a base station; monitoring and discovering active nodes around in the universal channel monitoring window; when an active node is found, the terminal sends a first active node list to the base station.