CN104684047A - Method and device for discovering small cell in heterogeneous communication network - Google Patents

Abstract

The present invention provides a solution for discovering/identifying small cells in a heterogeneous communication network. The macro base station judges whether the user equipment is approaching based on the location range information of each small cell in the macro cell and the estimated location information of the user equipment. One or more small cells, if yes, send a dedicated signaling to the user equipment, and the user equipment triggers a search based on the dedicated signaling to periodically search for the one or more small cells. The present invention also provides another solution for discovering small cells. The user equipment judges the user equipment based on the received position range information of the warning area of each small cell broadcast by the macro base station and the estimated position information of the user equipment. Whether one or more small cells are approached, and if yes, a search is triggered to periodically search for the one or more small cells. The present invention can more efficiently discover/identify the small cell in the heterogeneous communication network while saving the power consumption of the user equipment.

Description

Method and device for discovering small cells in a heterogeneous communication network

This application is a divisional application of the patent application with the application number 201110190014.0 filed on July 7, 2011, entitled "Method and Device for Discovering Small Cells in a Heterogeneous Communication Network".

technical field

The present application relates to a heterogeneous communication network (HetNet), and in particular to a method and device for discovering a small cell in a heterogeneous communication network.

Background technique

The existing closed subscriber group (CGS) cell discovery/identification scheme is based on the mechanism of autonomous search function (ASF) and proximity indication (proximity indication). One of its important goals is Reduce power consumption of user equipment. In this scheme, a white list (white list) is stored on the user equipment side, and the cell identification (cell ID) of a limited number of CGS cells associated with it is included on the white list. Information about a limited number of associated CGS cells, such as location range information, radio fingerprint information, and the like. The user equipment determines whether the user equipment is close to one or more CGS cells on its white list according to the stored location range information of a limited number of CGS cells associated with it and the estimated location information of the user equipment, if If yes, trigger a search to periodically search all CGS cells on the white list. During the search process, the user equipment determines the cell with the strongest measured signal strength on the white list as the target CGS cell, and sends a proximity indication to the macro base station to trigger the macro base station to prepare for handover, wherein the proximity indication Include the cell identity of the target CSG cell.

Existing CGS cell discovery/identification methods are based on the fact that user equipment is only associated with a limited number of CGS cells. Therefore, the user equipment can memorize the information of its associated CGS cell, such as location information, wireless footprint information, and the like. However, due to the large number of public pico cells, it is impossible for the user equipment to store the information of all these public pico cells. Therefore, the existing CGS cell discovery scheme is not suitable for the discovery of public pico cells. /identify.

At present, the discovery/identification of public picocells is only implemented through an exhaustive search method, which leads to relatively high power consumption of the user equipment. Therefore, it is necessary to provide a solution capable of solving this technical problem.

Contents of the invention

In view of the above problems, in the first aspect of the present invention, a method for assisting user equipment in discovering small cells in a macro base station of a heterogeneous communication network is provided, wherein the method includes the following steps: a. Based on the stored location range information of all small cells in the macro cell and the estimated location information of the user equipment, judging whether the user equipment has approached an area including one or more small cells; b. If the user equipment is close to the area, send dedicated signaling to the user equipment to inform the user equipment that it is close to the area, wherein the dedicated signaling includes all c. receiving an acknowledgment indication from the user equipment used to trigger the macro base station to prepare for handover, and perform handover preparation based on the acknowledgment indication, wherein the acknowledgment indication includes a target A cell identifier of a small cell, where the target small cell is a small cell with the strongest signal strength measured by the user equipment among the one or more small cells in the area.

And a method for discovering a small cell in a user equipment of a heterogeneous communication network is provided, wherein the method includes the following steps: A. receiving a message from the macro base station for informing the user equipment of its Dedicated signaling that has approached an area including one or more small cells, wherein the dedicated signaling includes cell identities of one or more small cells in the area; B. Based on the dedicated signaling, trigger Searching to periodically search for the one or more small cells in the area; C. Sending an acknowledgment indication to the macro base station to trigger the macro base station to prepare for handover, wherein the acknowledgment indication includes A cell identifier of the target small cell, where the target small cell is the small cell with the strongest signal strength measured by the user equipment among the one or more small cells in the area.

In the second aspect of the present invention, a method for assisting user equipment in discovering small cells in a macro base station of a heterogeneous communication network is provided, wherein the user equipment stores information of all frequently visited small cells Cell identity and location range information, the method includes the following steps: m. Based on the stored location range information of all small cells in the macro cell and the estimated location information of the user equipment, determine the user equipment Whether it has approached an area including one or more small cells; n. If the user equipment has approached the area, then determine whether the one or more small cells in the area all belong to the user equipment frequently The visited small cell; o. If not, send a dedicated signaling to the user equipment to inform the user equipment that it is close to the area, wherein the dedicated signaling includes Cell identities of one or more non-frequently visited small cells other than the small cells frequently visited by the user equipment; p. receiving an acknowledgment indication from the user equipment for triggering the handover preparation of the macro base station, and based on the acknowledgment Instructing to prepare for handover, wherein the acknowledgment indication includes a cell identity of a target small cell, and the target small cell is the one with the strongest signal strength measured by the user equipment among the one or more small cells in the area small community.

And a method for discovering small cells in a user equipment of a heterogeneous communication network is provided, wherein the user equipment stores cell identities and location range information of all frequently visited small cells, and the method The method includes the following steps: M. Based on the stored location range information of the frequently visited small cells and the estimated location information of the user equipment, determine whether the user equipment is close to one or more frequently visited small cells; N. If the user equipment is close to the one or more frequently visited small cells, trigger the search to periodically search for all the frequently visited small cells; O. Send an acknowledgment indication to the macro base station for triggering The macro base station prepares for handover, wherein the acknowledgment indication includes the cell identity of the target small cell, and the target small cell is the small cell with the strongest signal strength measured by the user equipment among all the frequently visited small cells .

Optionally, before the step O, the following step is also included: receiving a dedicated signaling from the macro base station for informing the user equipment that it has approached an area including one or more small cells, wherein the dedicated signaling The command includes the cell identities of one or more non-frequently visited small cells in the area except the small cell frequently visited by the user equipment; based on the dedicated signaling, a search is triggered to periodically search for the The one or more infrequently visited small cells in the area; wherein the step O includes: sending an acknowledgment indication to the macro base station for triggering the macro base station to prepare for handover, wherein the acknowledgment indication includes a target The cell identifier of the small cell, the target small cell is the small cell with the strongest signal strength measured by the user equipment among all the frequently visited small cells and the one or more non-frequently visited small cells in the area district.

In a third aspect of the present invention, a method for discovering small cells in a user equipment of a heterogeneous communication network is provided, wherein the method includes the following steps: i. Based on all the obtained small cells The location range information of the warning area and the estimated location information of the user equipment to determine whether the user equipment is close to an area including one or more small cells, wherein the coverage of the warning area of the small cell is greater than or equal to the the normal coverage of the small cell; ii. if the user equipment is close to the area, trigger a search to periodically search for the one or more small cells in the area; iii. send an acknowledgment indication to the macro base station, configured to trigger the macro base station to prepare for handover, wherein the acknowledgment indication includes the cell identity of the target small cell, and the target small cell is the user equipment in the one or more small cells in the area The small cell with the strongest measured signal strength.

And a method for assisting user equipment in discovering small cells in a macro base station of a heterogeneous communication network is provided, wherein the method includes the following steps: 1. broadcasting all activated cells within the coverage of the macro base station The location range information of the warning area of the small cell, wherein the coverage of the warning area of the small cell is greater than or equal to the normal coverage of the small cell; II. receiving a message from the user equipment used to trigger the macro base station to prepare for handover and perform handover preparation based on the confirmation indication, wherein the confirmation indication includes a cell identity of a target small cell, and the target small cell is the user in the one or more small cells in the area The small cell with the strongest signal strength measured by the device.

In a fourth aspect of the present invention, there is provided a method for discovering a small cell in a user equipment of a heterogeneous communication network, characterized in that the method includes the following steps: x. receiving the broadcast by the macro base station The location range information of the warning areas of all enabled small cells within the coverage of the macro base station, wherein the coverage of the warning areas of the small cells is greater than or equal to the normal coverage of the small cells; y. Based on all received The location range information of the warning area of the activated small cell triggers a search to periodically search for all activated small cells within the coverage of the macro base station.

It should be noted that, the small cell (small cell) in this paper includes but not limited to: pico cell (pico cell), femto cell (femto cell).

By applying the technical solution of the present invention, it is possible to more efficiently discover/identify small cells in a heterogeneous communication network while saving power consumption of user equipment. In addition, compared with the technical solution of the first aspect above, the above technical solution of the second aspect can save signaling overhead to a certain extent.

In addition, in an embodiment of the present invention, a device for assisting user equipment in discovering a small cell in a macro base station of a heterogeneous communication network is provided, wherein the device includes: a first judging device configured by Based on the stored location range information of all small cells in the macro cell and the estimated location information of the user equipment, judging whether the user equipment has approached an area including one or more small cells; the second A sending device, configured to send dedicated signaling to the user equipment if the user equipment is close to the area, for informing the user equipment that it is close to the area, wherein the dedicated signaling includes Cell identities of the one or more small cells in the area; first receiving means, configured to receive an acknowledgment indication from the user equipment for triggering the handover preparation of the macro base station, and based on the acknowledgment indication performing handover preparation, wherein the acknowledgment indication includes a cell identity of a target small cell, and the target small cell is a small cell with the strongest signal strength measured by the user equipment among the one or more small cells in the area district.

In one embodiment of the present invention, a device for discovering a small cell in a user equipment of a heterogeneous communication network is provided, wherein the device includes: a second receiving device, configured to receive the Dedicated signaling of the macro base station for informing the user equipment that it is approaching an area including one or more small cells, wherein the dedicated signaling includes cell identities of one or more small cells in the area; The first searching means is configured to trigger a search based on the dedicated signaling to periodically search for the one or more small cells in the area; the second sending means is configured to send an acknowledgment indication to the macro base station, configured to trigger the macro base station to prepare for handover, wherein the acknowledgment indication includes the cell identity of the target small cell, and the target small cell is the user equipment in the one or more small cells in the area The small cell with the strongest measured signal strength.

In another embodiment of the present invention, a device for assisting user equipment in discovering small cells in a macro base station of a heterogeneous communication network is provided, wherein the user equipment stores all frequently visited small cells cell identity and location range information, the device includes: a second judging device, configured to judge based on the stored location range information of all small cells in the macro cell and the estimated location information of the user equipment Whether the user equipment has approached an area including one or more small cells; third judging means, for if the user equipment has approached the area, judge whether the one or more small cells in the area Whether all the cells belong to the small cells frequently visited by the user equipment; the third sending means is used to send dedicated signaling to the user equipment if not, to inform the user equipment that it is close to the area, wherein The dedicated signaling includes cell identities of one or more infrequently visited small cells in the area other than the frequently visited small cells by the user equipment; a third receiving means is configured to receive An acknowledgment indication used to trigger the macro base station to prepare for handover, and prepare for handover based on the acknowledgment indication, wherein the acknowledgment indication includes the cell identity of the target small cell, and the target small cell is the A small cell with the strongest signal strength measured by the user equipment among one or more small cells.

In another embodiment of the present invention, a device for discovering small cells in a user equipment of a heterogeneous communication network is provided, wherein the user equipment stores cell identities of all frequently visited small cells and location range information, the device includes: a fourth judging device, configured to judge whether the user equipment is close to a location based on the stored location range information of the frequently visited small cell and the estimated location information of the user equipment or a plurality of frequently visited small cells; the second searching means is configured to trigger a search if the user equipment is close to the one or more frequently visited small cells, so as to periodically search for all the frequently visited small cells cell; a fourth sending device, configured to send an acknowledgment indication to the macro base station, and trigger the macro base station to prepare for handover, wherein the acknowledgment indication includes a cell identity of a target small cell, and the target small cell is the Among all the above-mentioned frequently visited small cells, the small cell with the strongest signal strength measured by the user equipment is selected.

In another embodiment of the present invention, a device for discovering a small cell in a user equipment of a heterogeneous communication network is provided, wherein the device includes: a fifth judging device, configured to The location range information of the warning areas of all small cells and the estimated location information of the user equipment, to determine whether the user equipment is close to an area including one or more small cells, wherein the coverage of the warning areas of the small cells The range is greater than or equal to the normal coverage range of the small cell; the third searching means is configured to trigger a search if the user equipment is close to the area, so as to periodically search for the one or more small cells in the area cell; the fifth sending device is configured to send an acknowledgment instruction to the macro base station, and is used to trigger the macro base station to prepare for handover, wherein the acknowledgment instruction includes a cell identifier of a target small cell, and the target small cell is the area The small cell with the strongest signal strength measured by the user equipment among the one or more small cells.

In another embodiment of the present invention, a device for assisting user equipment in discovering a small cell in a macro base station of a heterogeneous communication network is provided, wherein the device includes: a broadcasting device for broadcasting the The position range information of the warning areas of all activated small cells within the coverage of the macro base station, wherein the coverage of the warning areas of the small cells is greater than or equal to the normal coverage of the small cells; the fourth receiving device is used to receive information from The acknowledgment indication of the user equipment used to trigger the macro base station to prepare for handover, and perform handover preparation based on the acknowledgment indication, wherein the acknowledgment indication includes the cell identity of the target small cell, and the target small cell is the area The small cell with the strongest signal strength measured by the user equipment among the one or more small cells.

In yet another embodiment of the present invention, a device for discovering a small cell in a user equipment of a heterogeneous communication network is provided, wherein the device includes: a fourth receiving device, configured to receive The location range information of the warning areas of all enabled small cells within the coverage area of the macro base station broadcast by the station, wherein the coverage area of the warning area of the small cell is greater than or equal to the normal coverage area of the small cell; the fourth search means, The method is used for triggering a search based on the received location range information of warning areas of all enabled small cells, so as to periodically search for all enabled small cells within the coverage of the macro base station.

Various aspects of the present invention will be clarified through the description of specific embodiments below.

Description of drawings

These and other features of the present invention will become clearer by reading the detailed description of non-limiting embodiments made with reference to the following drawings:

FIG. 1 is a network topology diagram of a heterogeneous communication network according to an embodiment of the present invention;

Fig. 2 shows a flowchart of a method for discovering a small cell in a heterogeneous communication network according to an embodiment of the first aspect of the present invention;

Fig. 3 shows a flowchart of a method for discovering a small cell in a heterogeneous communication network according to an embodiment of the second aspect of the present invention;

Fig. 4 shows a flowchart of a method for discovering a small cell in a heterogeneous communication network according to an embodiment of the third aspect of the present invention;

FIG. 5 is a network topology diagram of a heterogeneous communication network according to another embodiment of the present invention;

Fig. 6 shows a flowchart of a method for discovering a small cell in a heterogeneous communication network according to an embodiment of the fourth aspect of the present invention.

The same or similar reference signs in the drawings indicate the same or similar components.

Detailed ways

It should be noted that, the small cell (small cell) in this paper includes but not limited to: pico cell (pico cell), femto cell (femto cell).

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

Fig. 1 shows a network topology diagram of a heterogeneous communication network according to an embodiment of the present invention. The big ellipse in the figure is the coverage area of the macro cell MC, that is, the macro base station (macro eNodeB) 10. Multiple pico cells (pico cells) are deployed in the macro cell MC, for example, the small elliptical pico cells PC1, pico cells PC2, and pico cells PC3 shown in the figure. Also shown in the figure is a user equipment 20 moving in the macro cell MC, handover between the macro cell and the pico cells.

It should be noted that in FIG. 1, although only three pico cells PC1, PC2, and PC3 are shown in the macro cell MC, those skilled in the art can understand that in practical applications, the pico cells in the macro cell MC The number of cells is not limited to three, in addition, the macro cell MC may also include multiple femtocells. Another thing to be noted is that in practical applications, the number of user equipments in the macro cell MC is not limited to one. Therefore, FIG. 1 is only an exemplary object, and does not constitute a limitation to the protection scope of the present invention.

Fig. 2 shows a flowchart of a method for discovering small cells in a heterogeneous communication network according to an embodiment of the first aspect of the present invention. The method for discovering a small cell according to the first aspect of the present invention will be described below with reference to FIG. 2 and in combination with FIG. 1 .

In this embodiment, the macro base station 10 stores cell identities, location range information, and the like of all the pico cells PC1, PC2, and PC3 in the macro cell MC. In addition, the macro base station 10 has the ability to locate the user equipment 20 , that is, to estimate the location information of the user equipment 10 .

2, first, in step S21, the macro base station 10 judges whether the user equipment 20 is based on the stored location range information of all the pico cells PC1, PC2 and PC3 in the macro cell MC and the estimated location information of the user equipment 20. Having approached an area including one or more pico cells, for example, the macro base station 10 may perform this determination periodically.

If the judgment result shows that the user equipment 20 is close to such an area, for example, the user equipment 20 has moved close to the area where the pico cells PC1 and PC2 are located, then in step S22, the macro base station 10 sends dedicated signaling to the user equipment 20, for notifying the user equipment 20 that it is approaching the area where the pico cells PC1 and PC2 are located. The dedicated signaling includes the cell identities of the pico cells PC1 and PC2.

Next, in step S23, the user equipment 20 receives the dedicated signaling from the macro base station 10, and based on the cell identities of the pico cells PC1 and PC2 included in the dedicated signaling, triggers a search to periodically search for the pico cells PC1 and PC2 PC2.

That is to say, the user equipment 20 periodically measures the strength of the signals from the pico cells PC1 and PC2, for example, performing reference signal receiving power (reference signal receiving power, RSRP) measurement, and the pico cell with the strongest signal strength, such as the pico cell The cell PC1 serves as the target pico small cell to be handed over.

Then, in step S24, the user equipment 20 sends an acknowledgment indication (acknowledge indication) to the macro base station 10 for triggering the macro base station 10 to prepare for handover. The acknowledgment indication includes the cell identity of the target small cell, that is, the pico cell PC1.

Next, in step S25, the macro base station 10 receives an acknowledgment indication from the user equipment 20, and performs handover preparation based on the acknowledgment indication.

Fig. 3 shows a flowchart of a method for discovering small cells in a heterogeneous communication network according to an embodiment of the second aspect of the present invention. The method for discovering a small cell according to the second aspect of the present invention will be described below with reference to FIG. 3 and in combination with FIG. 1 .

In this embodiment, at the user equipment 20 side, the user equipment 20 stores cell identities and location range information of all pico cells that it frequently visits. For example, the pico cell PC1 and the pico cell PC3 are pico cells frequently visited by the user equipment 20 , therefore, information such as cell identifiers and location range information of the pico cells PC1 and PC3 are stored in the user equipment 20 . Furthermore, the user equipment 20 has the ability to estimate its own location information.

On the macro base station 10 side, the macro base station 10 stores the cell identities and location range information of all the pico cells PC1, PC2 and PC3 in the macro cell MC, and knows the cell identities of the pico cells that the user equipment 20 frequently visits. In addition, the macro base station 10 has the ability to locate the user equipment 20 , that is, to estimate the location information of the user equipment 10 .

First, in step S31, the macro base station 10 judges whether the user equipment 20 has approached a user equipment 20 based on the stored location range information of all the pico cells PC1, PC2 and PC3 in the macro cell MC and the estimated location information of the user equipment 20. An area including one or more pico cells, for example, the macro base station 10 may periodically perform this determination.

If the judgment result shows that the user equipment 20 has approached such an area, for example, the user equipment 10 has moved close to the area where the pico cells PC1 and PC2 are located, then in step S32, the macro base station 10 judges whether the pico cells PC1 and PC2 in the area are All belong to pico cells frequently visited by the user equipment 20 .

At the same time, since the user equipment 20 has moved close to the area where the pico cells PC1 and PC2 are located, the user equipment 20 according to the stored location range information of all the pico cells that it frequently visits, that is, the pico cells PC1 and PC3 and the estimated According to the location information of the user equipment 20, it is determined that the user equipment 20 is close to the pico cell PC1 that it frequently visits, then at this time, in step S32', the user equipment 20 triggers the search to periodically search for all the frequently visited The pico cells, that is, the pico cells PC1 and PC3.

On the side of the macro base station 10, the above-mentioned step S32 is followed. In this embodiment, since the pico cell PC2 in this area does not belong to the pico cell frequently visited by the user equipment 20, in step S33, the macro base station 10 Sending dedicated signaling to the user equipment 20, the dedicated signaling only includes the cell identifiers of the infrequently visited pico cells PC2 in the area except the pico cells PC1 frequently visited by the user equipment 20, that is, the macro base station 10 Only cell identities belonging to infrequently visited pico cells in this area are sent to the user equipment 20 by dedicated signaling.

Next, in step S34, the user equipment 20 receives the dedicated signaling from the macro base station 10, and triggers a search based on the cell identity of the pico cell PC2 included in the dedicated signaling, so as to periodically search for the pico cell PC2.

Based on the triggering of the above two searches, the user equipment 20 searches for the pico cell PC2 and all its frequently visited pico cells at the same time, that is to say, the user equipment 20 periodically measures , that is, the signal strengths of pico cells PC1 and PC3, for example, perform reference signal receiving power (reference signal receiving power, RSRP) measurement, and use the pico cell with the strongest signal strength, such as pico cell PC1, as the target pico cell to be handed over small community.

Then, in step S35, the user equipment 20 sends an acknowledgment indication (acknowledge indication) to the macro base station 10 for triggering the macro base station 10 to prepare for handover. The acknowledgment indication includes the cell identity of the target small cell, that is, the pico cell PC1.

Next, in step S36, the macro base station 10 receives the acknowledgment indication from the user equipment 20, and performs handover preparation based on the acknowledgment indication.

It should be noted that, in this embodiment, if one or more pico cells included in the area close to the user equipment 20 all belong to the pico cells that they frequently visit, then the macro base station 10 will not send dedicated signaling, and the user equipment 20 will The device 20 then automatically triggers a search to periodically search for all picocells it frequently visits.

Fig. 4 shows a flowchart of a method for discovering a small cell in a heterogeneous communication network according to an embodiment of the third aspect of the present invention. The method for discovering a small cell according to the third aspect of the present invention will be described below with reference to FIG. 4 and in combination with FIG. 5 .

In this embodiment, at the user equipment 20 side, the user equipment 20 has the capability of estimating its own location information.

In addition, since the mobility of the user equipment 20 is generally fast, in this embodiment, an alert zone (alert zone) of the pico cell is set for each pico cell. Preferably, as shown in FIG. 5 , the alert zone of the pico cell The coverage of area AZ, that is, the area within the dotted line in FIG. 5 is larger than the normal coverage of the pico cell itself, so that the user equipment can be handed over to the pico cell more successfully when approaching the pico cell. Certainly, the coverage of the warning area of the pico cell may also be equal to the normal coverage of the pico cell itself.

On the side of the macro base station 10, the macro base station 10 stores the cell identities of all the pico cells in the macro cell MC and the position range information of the warning areas of these pico cells. The macro base station 10 will broadcast the location range information of the warning areas of the activated pico cells in the macro cell MC. For example, the macro base station 10 may broadcast periodically or whenever a new pico cell is activated.

Referring to Fig. 4, at first, in step S41, the macro base station 10 broadcasts the location range information of the warning areas of all enabled pico cells within the coverage of the macro base station 10, for example, the positions of the warning areas of the pico cells PC1, PC2 and PC3 scope information.

Next, in step S42, the user equipment 20 judges whether the user equipment 20 is close to a location including one or more The area of a picocell.

The judgment result shows that the user equipment 20 is close to such an area, for example, the user equipment 20 has moved close to the area where the pico cells PC1 and PC2 are located, then in step S43, the user equipment 20 triggers a search to periodically search for the pico cells PC1 and PC2.

That is to say, the user equipment 20 periodically measures the strength of the signals from the pico cells PC1 and PC2, for example, performing reference signal receiving power (reference signal receiving power, RSRP) measurement, and the pico cell with the strongest signal strength, such as the pico cell The cell PC1 serves as the target pico cell to be handed over.

Then, in step S44, the user equipment 20 sends an acknowledgment indication to the macro base station 10 for triggering the macro base station 10 to prepare for handover. The acknowledgment indication includes the cell identity of the target pico cell, that is, the pico cell PC1.

Next, in step S45, the macro base station 10 receives an acknowledgment indication from the user equipment 20, and performs handover preparation based on the acknowledgment indication.

It should be noted that, in an alternative embodiment, each pico cell may itself broadcast the location range information of the warning area of the pico cell.

Fig. 6 shows a flowchart of a method for discovering a small cell in a heterogeneous communication network according to an embodiment of the fourth aspect of the present invention. The method for discovering a small cell according to the fourth aspect of the present invention will be described below with reference to FIG. 6 and in conjunction with FIG. 5 .

In this embodiment, the user equipment 20 does not have the ability to estimate its own location information, or cannot estimate its own location information accurately, or cannot estimate its own location information in a power-saving manner, therefore, it cannot use the above third aspect The discovery/identification of the pico cell is performed in the same manner as in the embodiment.

In this embodiment, referring to FIG. 6 , first, in step S61, the macro base station 10 broadcasts the position range information of the warning areas of all activated pico cells within the coverage area of the macro base station 10, for example, the pico cells PC1, PC2 and The location range information of the warning area of PC3.

Next, in step S62 , the user equipment 20 receives the position range information of the warning areas of all enabled pico cells within the coverage of the macro base station 10 broadcast by the macro base station 10 .

Then, in step S63 , the user equipment 20 triggers a search based on the received location range information of warning areas of all activated pico cells, so as to periodically search for all activated pico cells within the coverage area of the macro base station 10 .

In this embodiment, since the user equipment 20 triggers the search only after receiving the location range information of the warning area of the pico cell broadcast by the macro base station, that is, when the user equipment 20 enters a small cell that is not deployed, For example, in the macro cells of pico cells and femto cells, since the macro base station in the macro cell will not broadcast the location range information of the warning area, the user equipment 20 will not trigger the search, thereby saving the user equipment 20 to a certain extent. power consumption.

It will be apparent to those skilled in the art that the invention is not limited to the details of the above-described exemplary embodiments, but that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be regarded as exemplary and not restrictive from all points of view, and any reference sign in a claim should not be construed as limiting the claim concerned. Furthermore, it is obvious that the word "comprising" does not exclude other elements or steps, and the word "a" preceding an element does not exclude the inclusion of "plurality" of such elements. Multiple elements stated in a product claim may also be realized by one element through software or hardware. The words first, second, etc. are used to denote names and do not imply any particular order.

Claims (6)

1. in the subscriber equipment of heterogeneous communications network for finding a method for small-cell, it is characterized in that, said method comprising the steps of:

I. based on the position range information in the warning region of obtained all small-cells and the positional information of this estimated subscriber equipment, judge whether this subscriber equipment has comprised the region of one or more small-cell close to one, the coverage in the warning region of wherein said small-cell is more than or equal to the normal coverage areas of described small-cell;

If ii. this subscriber equipment is close to described region, then triggering searches, periodically to search for the described one or more small-cell in described region;

Iii. send and confirm that instruction is to macro base station, switching preparation is carried out for triggering described macro base station, wherein saidly confirm that instruction comprises the cell ID of target small-cell, described target small-cell is the small-cell that signal strength signal intensity that in the described one or more small-cell in described region, this subscriber equipment measures is the strongest.

2. in the macro base station of heterogeneous communications network, find a method for small-cell for assisting user equipment, it is characterized in that, said method comprising the steps of:

I. broadcast the position range information in the warning region of all small-cells of having opened in this macro base station coverage, the coverage in the warning region of wherein said small-cell is more than or equal to the normal coverage areas of described small-cell;

II. the confirmation instruction carrying out switching preparation for triggering this macro base station from described subscriber equipment is received, and carry out switching preparation based on described confirmation instruction, wherein said confirmation instruction comprises the cell ID of target small-cell, the small-cell that the signal strength signal intensity that described target small-cell measures for subscriber equipment described in the described one or more small-cell in described region is the strongest.

3. in the subscriber equipment of heterogeneous communications network for finding a method for small-cell, it is characterized in that, said method comprising the steps of:

X. receive the position range information in the warning region of all small-cells of having opened in this macro base station coverage of being broadcasted by macro base station, the coverage in the warning region of wherein said small-cell is more than or equal to the normal coverage areas of described small-cell;

Y. based on the position range information in the warning region of received all small-cells of having opened, triggering searches, periodically to search for all small-cells of having opened in described macro base station coverage.

4. in the subscriber equipment of heterogeneous communications network for finding a device for small-cell, it is characterized in that, described device comprises:

5th judgment means, for the position range information in the warning region based on obtained all small-cells and the positional information of this estimated subscriber equipment, judge whether this subscriber equipment has comprised the region of one or more small-cell close to one, the coverage in the warning region of wherein said small-cell is more than or equal to the normal coverage areas of described small-cell;

3rd searcher, if for this subscriber equipment close to described region, then triggering searches, periodically to search for the described one or more small-cell in described region;

5th dispensing device, confirm that instruction is to macro base station for sending, switching preparation is carried out for triggering described macro base station, wherein saidly confirm that instruction comprises the cell ID of target small-cell, described target small-cell is the small-cell that signal strength signal intensity that in the described one or more small-cell in described region, this subscriber equipment measures is the strongest.

5. in the macro base station of heterogeneous communications network, find a device for small-cell for assisting user equipment, it is characterized in that, described device comprises:

Broadcaster, for broadcasting the position range information in the warning region of all small-cells of having opened in this macro base station coverage, the coverage in the warning region of wherein said small-cell is more than or equal to the normal coverage areas of described small-cell;

4th receiving system, for receiving the confirmation instruction carrying out switching preparation for triggering this macro base station from described subscriber equipment, and carry out switching preparation based on described confirmation instruction, wherein said confirmation instruction comprises the cell ID of target small-cell, the small-cell that the signal strength signal intensity that described target small-cell measures for subscriber equipment described in the described one or more small-cell in described region is the strongest.

6. in the subscriber equipment of heterogeneous communications network for finding a device for small-cell, it is characterized in that, described device comprises:

4th receiving system, for receiving the position range information in the warning region of all small-cells of having opened in this macro base station coverage of being broadcasted by macro base station, the coverage in the warning region of wherein said small-cell is more than or equal to the normal coverage areas of described small-cell;

4th searcher, for the position range information in the warning region based on received all small-cells of having opened, triggering searches, periodically to search for all small-cells of having opened in described macro base station coverage.