WO2011085541A1

WO2011085541A1 - Method and apparatus for handover between cells

Info

Publication number: WO2011085541A1
Application number: PCT/CN2010/070140
Authority: WO
Inventors: 蒋琦; 沈钢; 张凯宾
Original assignee: 上海贝尔股份有限公司; 阿尔卡特朗讯
Priority date: 2010-01-12
Filing date: 2010-01-12
Publication date: 2011-07-21
Also published as: CN102598791A; CN102598791B

Abstract

For solving the Ping-Pong effect potentially generated by the cell handover in a heterogeneous network with different coverage of cells, the invention provides a method and an apparatus for handover between cells. When a User Equipment (UE) or a base station, based on the signal quality of the current cell and the signal quality of the neighboring cell during a handover detection time period (T_reselection), makes an initial determination that the UE should perform a handover to a neighboring cell, after a delay for a handover double check time window (T_check), the UE or the base station then, based on the signal quality of the current cell and the signal quality of the neighboring cell after the double check time window, determines whether the UE should perform a handover to the neighboring cell. The invention avoids unnecessary frequent handover generated in a heterogeneous network, especially when a UE moves rapidly in the heterogeneous network, improves the work efficiency of a home station, and has the compatibility to the existing UE or base station without the need of improving on both the UE and the base station.

Description

Method and device for inter-cell handover

The present invention relates to wireless communications, and more particularly to inter-cell handover techniques. Background technique

Currently, the LET-A standard has considered Heterogeneous Networks (HTN) technology to be considered within the scope of research. For the HTN system, an important application is to introduce a Home eNodeB (HeNB) into a traditional cell to support hot zone or hot spot, and indoor coverage. In this system, as shown in FIG. 1, a plurality of home base stations HeNB 1 and HeNB 2 services are usually present in a cell served by a macro base station (Macro eNodeB, MeNB for short) (the largest elliptical area in FIG. 1). The cells (two smaller elliptical regions in Figure 1). Since the transmission power of the home base station is low, the service area of the home base station is much smaller than the macro base station of the cell. When a User Equipment (UE) moves in a cell, it may traverse the cell served by the macro base station and the cell served by the home base station. When the user equipment moves fast, as shown in Figure 1, the user equipment may quickly pass through the cell served by the home base station from the cell served by the macro base station and return to the cell served by the macro base station.

In the current communication system, in order to improve the overall performance of the wireless communication, when the user equipment moves from the own cell to a neighboring cell, it usually switches from the base station jurisdiction of the own cell to the base station of the neighboring cell. Generally, the user equipment measures the signal quality of the reference signal (Preference) or the preamble (Preamble) of the received base station from the cell and the neighboring cell, respectively, and the signal quality of the signal from the base station of the neighboring cell. After a period of time is better than that from the local cell, the user equipment judges that it should switch to the neighboring cell, and then sends a handover request including the measurement result back to the base station of the local cell. The base station of the cell will perform subsequent handover processing according to the handover request, for example, determining whether the user equipment is handed over, issuing handover signaling, and the like.

In heterogeneous networks, especially when the user equipment moves very fast, the current switching method will produce a more serious Ping-Pong effect. As shown in Figure 1, first, at At time t!, the user equipment UE is in the cell served by the MeNB, and is served by the MeNB. The user equipment UE is moving in the direction of the arrow line in the figure. Next, at time t _2, the user equipment UE moves to a nearby cell and services HeNB 1, and the signal quality of the detected signal from the HeNB 1 to a continuously good quality of a signal from the MeNB to time t _3. Thus, at time t _3, the UE determines that it should switch to the HeNB 1 cell service, and sends back a handover request MeNB. MeNB permit a user equipment UE handover, the user equipment UE for the corresponding switching operation, and switches to 1 at time t ₄ by a service HeNB. However, since the moving speed of the user equipment (UE) fast, at time t ₄ it has moved out of range of a cell HeNB 1 and services, too late served by the HeNB 1. The signal quality of the signal it receives from the MeNB will continue to be better than the signal quality of the signal from the HeNB 1, so the user equipment UE will initiate a new handover procedure again, requesting handover back to be served by the MeNB. In this way, the ping-pong effect has taken place. These two handovers are not necessary as a whole, and will waste more signaling resources, and the services that the user equipment is performing may also be interrupted.

The current standard does not give a technical solution to solve this technical problem. Summary of the invention

The present invention is directed to addressing the ping-pong effect that may result from cell handover in a heterogeneous network.

According to a first aspect of the present invention, there is provided a method for initiating a cell handover in a user equipment, the user equipment measuring a first signal quality of a signal from a base station of a cell to which it belongs and a signal from a base station of a neighboring cell a second signal quality, the method comprising the steps of: determining whether a switching condition is satisfied according to the first and second signal quantities in a switching detection period; delaying a switching rechecking time when the switching condition is satisfied a window, and determining, according to the first and second signal qualities after the time window, whether a recheck condition is satisfied; when the recheck condition is satisfied, sending a handover request to the base station of the cell to which the handover request includes the first sum A second signal quality related signal quality measurement report.

Meanwhile, the present invention also provides an apparatus for initiating a cell handover in a user equipment, the user equipment measuring a first signal quality of a signal from a base station of a cell to which it belongs and a second signal of a signal of a base station from a neighboring cell Quality, the device comprises: a judging device, configured to determine a switch according to the first and second signal qualities in a handover detection period Whether the condition is satisfied; determining means, configured to determine whether a recheck condition is satisfied according to the first and second signal qualities after a switching recheck time window is satisfied when the switching condition is satisfied; and the transmitter is used for the rechecking When the condition is satisfied, a handover request is sent to the base station of the cell to which the signal includes a signal quality measurement report related to the first and second signal qualities.

The present invention also provides a user equipment comprising the above apparatus for initiating cell handover in a user equipment.

The first aspect of the present invention proposes a handover mechanism for performing double check on a cell handover in a user equipment, which avoids unnecessary frequent handover in a heterogeneous network and improves the working efficiency of the home base station. Moreover, the first aspect of the present invention only requires improvement of existing user equipment, without requiring any changes to existing home base stations and macro base stations, and compatibility with existing base stations.

According to a second aspect of the present invention, there is provided a method for initiating cell handover processing for a user equipment under control in a base station, the user equipment measuring a first signal quality of a signal from the base station and from a phase The second signal quality of the signal of the base station of the neighboring cell, the method includes the following steps: receiving a first handover request sent by the user equipment, where the first handover request is performed by the user equipment according to a first sum in a handover detection period The second signal quality is determined to be sent after the handover condition is satisfied; delaying a handover recheck time window, determining whether the second handover request sent by the user equipment is still received after the time window expires, the second handover request being The first and second signal quality after the time period determine that a handover condition is satisfied, and when the second handover request is received, start cell handover processing for the user equipment to the neighboring cell.

Meanwhile, the present invention also provides an apparatus for initiating cell handover processing for a user equipment under control in a base station, the user equipment measuring a first signal quality of a signal from the base station and a base station from a neighboring cell The second signal quality of the signal, the device includes: a receiver, configured to receive a first handover request and a second handover request sent by the user equipment, where the first handover request is performed by the user equipment according to a handover detection period Transmitting, by the user equipment, that a switching condition is satisfied according to the first and second signal qualities after the time period is determined by the first and second signal quality determining that the switching condition is satisfied; Used to determine whether the receiver is receiving the first cut Receiving the second handover request after a handover recheck time window after the request is changed; the processor, configured to: when the receiver receives the second handover request, perform the user equipment to the cell of the neighboring cell Switch processing.

The present invention also provides a base station comprising the above apparatus for initiating cell handover processing for a user equipment under jurisdiction in a base station.

The second aspect of the present invention proposes a handover mechanism for performing double check on a cell handover in a base station, which avoids unnecessary frequent switching in a heterogeneous network and improves the working efficiency of the home base station. Moreover, the second aspect of the present invention only needs to improve the existing base station, and does not need to make any changes to the existing user equipment, and has compatibility with the existing user equipment. DRAWINGS

The above and other features, objects, and advantages of the present invention will become more apparent from the detailed description of the accompanying drawings.

1 is a schematic diagram of a user equipment moving between a cell under the jurisdiction of a macro base station of a heterogeneous network and a cell under the jurisdiction of a home base station;

2 is a schematic diagram of a user equipment moving between a cell under the jurisdiction of a macro base station of a heterogeneous network and a cell under the jurisdiction of a home base station according to an embodiment of the present invention;

3 is a flowchart of a method for initiating cell switching in a user equipment according to a first embodiment of the present invention;

4 is a flow chart of a method for initiating cell handover processing for a user equipment under the jurisdiction in a base station according to a first embodiment of the present invention.

In the figures, the same or similar reference numerals denote the same or similar components. detailed description

This detailed description describes the inventive concept of the present invention by taking the heterogeneous network to which the present invention is applied to the LTE-A standard as an example. It will be understood that the present invention is not limited thereto, and the present invention is also applicable to switching between cells of any heterogeneous network or homogeneous network.

As shown in FIG. 2, the user equipment UE is in a cell managed by the macro base station MeNB1. (larger elliptical area on the left side in Figure 2). The user equipment UE moves in the direction indicated by the arrow, and first passes through the cell under the jurisdiction of the home base station HeNB 1 (the smaller elliptical region below the cell under the jurisdiction of the macro base station MeNB 1) and returns to the macro base station MeNB 1 Next, it moves from the cell under the jurisdiction of the macro base station MeNB 1 to the cell under the jurisdiction of the macro base station MeNB 2 (the larger elliptical area on the right side in Fig. 2).

The user equipment UE measures the signal quality of the reference signal or the preamble signal transmitted by all base stations received in each subframe. In this embodiment, the signal quality can be Reference Signal Receving Power (RSRP) or Reference Signal Receving Quality (RSRQ).

First embodiment

In the first embodiment, the user equipment UE performs repeated detection on whether or not to switch. The user equipment UE in the first embodiment includes a judging device, a determining device and a transmitter.

Referring to FIG. 2, first, at time ^, the user equipment UE is in the cellular cell served by the MeNB 1, and is served by the MeNB 1.

Then, at time t ₂ , the user equipment UE moves to the vicinity of the cell served by the HeNB 1, and it receives the reference signals respectively transmitted by the MeNB 1 and the HeNB 1. The user equipment UE measures the first signal quality 0_ of the reference signal transmitted by the MeNB 1, and measures the received second signal quality of the HeNB 1 to transmit the reference signal.

As shown in FIG. 3, in step S30, the determining means of the user equipment UE determines whether a switching condition is satisfied _according to the first signal quality 2 .. and the second signal quality Q within a handover detecting period T _lection .

Specifically, in an embodiment similar to the prior art, the user equipment UE calculates the first indicator R at time t ₂ using the following formula (1):

Where Q is the hysteresis factor specified in an existing standard for avoiding ping-pong effects. And, the user equipment UE calculates the second indicator R _n at time t ₂ using the following formula (2):

^υ , ( 2 ) where is the offset used to control frequency or cell characteristics as specified in an existing standard Coefficient.

The user equipment UE compares the sizes of the first indicator and the second indicator. Since the user equipment UE is closer to HeNB 1, the second indicator at time t _{2 is} greater than the first indicator. In this case, the user equipment UE initiates a timing of the handover detection period T.

In the detection period 7 _eie/ec ^, the first signal quality 0_..,., and the HeNB 1 of the reference signal transmitted by the MeNB 1 measured by the user equipment UE in each subframe are transmitted by the reference signal. Second signal quality. After the signal quality is obtained for each measurement, the user equipment UE calculates the first index R _s and the second index R _n at that moment. The judging device judges whether the second index is greater than the first index? ,. If it is greater, it will continue to judge the next measurement and calculation result; if it is less than, it will end.

The detection period is 7 ^^. "After the time t ₃ to time. Analyzing apparatus according to the detection period r _{rae / ecri"} second duration greater than the first index index?.,., Determined that the switching condition is satisfied.

The process of determining whether the handover condition is satisfied is similar to whether the existing user equipment determines whether to perform cell handover. It can be understood that the specific manner of the determining step is not limited thereto, and those skilled in the art can use other user equipments to initially determine whether the user equipment should be performed based on the received signal quality of the base station of the local cell and the neighboring cell. The technical solution of switching is used instead of the above specific method. These solutions for preliminarily determining whether the user equipment should be handed over are within the scope of the claims of the present invention.

After the time t ₃ the user equipment UE judges that the switching condition is satisfied, the UE starts a time window of 7 review / ^ timing.

After the recheck time window 7 / ^, the time comes to t ₄ time. Due to the fast moving speed of the user equipment UE, it has actually moved out of the cell range governed by the HeNB 1. In this case, it is not necessary for the user equipment UE to handover to the HeNB 1, and it is also immediately switched back to the MeNB 1.

At time t _4, in step S31, the user equipment UE is determined according to the means 7 / ^ the first and second signal quality after the time window, determining a re-inspection condition is satisfied.

Specifically, in an embodiment similar to the existing mode, the user equipment UE determines the first indicator R _x at time t ₄ using the foregoing formula (1), and uses the foregoing formula (2) calculating a second index of time t _4.

At time t _4, at the moment, the user equipment UE far away from the HeNB l, less than the first indicator has a second index, the user equipment UE retest determination condition is not satisfied.

In this case, the user equipment UE does not send a handover request to the MeNB 1, and does not initiate the handover procedure. In this way, unnecessary switching between the MeNB 1 and the HeNB 1 is avoided, and the working efficiency of the home base station is improved.

Next, at time t _5, the user equipment UE moves to a nearby cell 2 MeNB and services, it receives the MeNB MeNB. 1 and 2 the reference signal transmitted from each. The user equipment UE measures the first signal quality 0_. of the reference signal transmitted by the MeNB 1, and measures the received second signal quality of the MeNB 2 to transmit the reference signal.

In step S32, the determining means of the user equipment UE determines whether a switching condition is satisfied according to the first signal quality and the second signal quality ^ within a handover detecting period 7^^^.

Specifically, the user equipment UE calculates the first indicator R _n at time t ₅ using the foregoing formula (1), and calculates the second indicator at time t ₅ using the following formula (3).

Rn ~ Qmeas.n + Qojfset (3) where is the offset coefficient specified in an existing standard for controlling frequency or cell characteristics.

The user equipment UE compares the sizes of the first indicator and the second indicator. Since the user equipment UE from the MeNB 2 close, at time t ₅ a second indicator /? Is greater than the first index. In this case, the user equipment UE initiates a handover detection period 7^ _e/ ^. „ Timing.

During the detection period T _resekcii . "The ή ^1, the signal quality of the first reference signal is a user equipment UE in each subframe are measured MeNB 1 transmission, and transmits the reference signal MeNB 2 a second signal quality Q _mca,". After the signal quality is obtained for each measurement, the user equipment UE calculates the first indicator R _s and the second indicator R at the moment. The determining device determines whether the second indicator is greater than the first indicator. If it is greater, it will continue to judge the next measurement and calculation result; if it is less than, it will end.

After the detection period ^^^, the time t ₆ to time. Judging device based During the detection period 7^ _e/erti . The second indicator is continuously larger than the first indicator, and the switching condition is judged to be satisfied.

After the time t ₆ the user equipment UE judges that the switching condition is satisfied, the UE starts a time window of 7 review / ^ timing.

After the recheck time window T _eheek , the time comes to time t ₇ . The user equipment UE has moved out of the cell range governed by the MeNB 1 and entered the range of the cell under the jurisdiction of the MeNB 2. In this case, it is necessary for the user equipment UE to handover to the MeNB 2.

At time t _7, in step S33, the user equipment UE determining means 0 _.,., And determining a second signal quality review condition is satisfied after the first signal quality in accordance with the time window.

Specifically, the user equipment UE determines the first indicator R _S at time t ₇ using the foregoing formula (1), and calculates the second indicator at time t ₇ using the foregoing formula (3).

At time t _7, the user equipment UE far away MeNB 1, 2 closer from the MeNB, the second index _Rn 'is still greater than the first index R _S, the determination means determines review condition is satisfied.

In step S34, the transmitter of the user equipment UE sends a handover request to the associated MeNB 1, the handover request including a signal quality measurement report related to the first signal quality Q and the second signal quality C, and the handover procedure is initiated.

After receiving the handover request, the MeNB 1 comprehensively determines whether the user equipment UE performs handover and sends corresponding signaling. The operations performed by the MeNB 1 are all existing in the prior art, and the present invention will not be described herein.

In the first embodiment, only the existing user equipment UE needs to be improved, and there is no need to make any changes to the existing home base station HeNB and the macro base station MeNB, and compatibility with the existing base station eNB.

The user equipment UE moves from the cell range governed by the home base station HeNB 1 to the cell range governed by the home base station HeNB 1 and returns to the cell range governed by the MeNB 1 and moves from the cell range governed by the MeNB 1 to the macro base. The first aspect of the present invention is described by taking two cases of the cell range governed by the station MeNB 2. It will be understood that the present invention is not limited thereto, and the present invention is equally applicable in the case where the user equipment UE moves from the range under the jurisdiction of a home base station to the range governed by a macro base station, and in other cases. Second embodiment

In the first embodiment, whether or not the handover is repeated detection is performed by the base station _e NB . The macro base station MeNB in the second embodiment includes a receiver, a judging device, and a processor.

Still referring to FIG. 2, first, at time ^, the user equipment UE is in the cell served by the MeNB 1, and is served by the MeNB 1.

Then, at time t ₂ , the user equipment UE moves to the vicinity of the cell served by the HeNB 1, and it receives the reference signals respectively transmitted by the MeNB 1 and the HeNB 1. The user equipment UE measures the first signal quality 0_.,. of the reference signal transmitted by the MeNB 1, and measures the received second signal shield amount β of the HeNB 1 to transmit the reference signal.

The user equipment UE determines whether a handover condition is satisfied according to the first signal quality 2 and the second signal shield amount in a handover detection period Τ.

Specifically, in a preferred embodiment with the conventional embodiment in a similar manner, the UE user equipment (2) a second time t ₂ is calculated using the above equation (1) calculates the time t ₂ of the first index, and using the above equation index.

In the detection period T _reselection , the user equipment UE measures the first signal quality of the reference signal transmitted by the MeNB 1 and the second signal quality Q of the HeNB 1 transmission reference signal in each subframe. After the signal quality is obtained for each measurement, the user equipment UE calculates the first indicator and the second indicator at the moment. The user equipment UE determines whether the second indicator is greater than the first indicator, if it is greater than, then continues to determine the next measurement and calculation result; if not, it ends.

After the detection period T _selection, time t ₃ to time. The user equipment UE is based on the detection period 7 _{ee /} ^. If the second indicator is continuously greater than the first indicator?, and the handover condition is satisfied, the user equipment UE directly sends a handover request to the associated MeNB 1, the handover request including the first signal quality Q and the second signal quality. Q related signal quality measurement report, start the switching process. The above techniques for the user equipment UE to perform signal quality detection, determine and initiate the handover procedure are known in the prior art. Moreover, any other technical solution that the user equipment UE initiates the handover procedure is applicable to the second embodiment.

In step S40, the receiver of the base station MeNB 1 receives the handover request sent by the user equipment UE.

Preferably, in step S41, the base station MeNB 1 determines the base station HeNB 1 of the neighboring cell according to the handover request and the topology of the network where the base station is located, and then determines a recheck time window time window T _check

The base station MeNB 1 then initiates the timing of the recheck time window 7 during which the MeNB 1 does not send signaling to control the user equipment UE handover or non-handover to the user equipment UE.

Since the user equipment UE does not receive the signaling sent by the MeNB 1, the user equipment UE continues to measure the first signal quality Q and the second signal quality Q in each frame, and calculates the first indicator R _s and the second indicator R _{n at the} moment. And determine whether the second indicator is greater than the first indicator. If it is greater, the handover request is continued to be sent to the MeNB 1. If it is smaller, the handover request is not sent.

During the recheck time window, the user equipment UE moves quickly, and it has actually passed through the cell range governed by HeNB 1. In this case, the user equipment UE does not have to switch to the jurisdiction of the HeNB 1. After the second indicator of the user equipment UE has been calculated by the user equipment UE, the second indicator that is calculated by the user equipment UE is no longer sent to the MeNB 1 for the handover request.

After the time window T _check Zhong review, time to time t _4, in a step S42, the determination means determines the base station MeNB receiver is in the first window of time after receiving the re-examination handover request received after 7 _½ ^ Go to the switch request.

Since the user equipment UE has no longer transmitted the handover request, the determining means of the MeNB determines that the receiver has not received the handover request after the recheck time window 7 _{Arat has} elapsed. In this case, the base station MeNB 1 does not initiate the handover procedure. In this way, unnecessary handover between the MeNB 1 and the HeNB 1 is avoided, and the working efficiency of the home base station is improved.

Then, at time t ₅ , the user equipment UE moves to the cell of the cell served by the MeNB 2 Nearly, it receives the reference signals respectively transmitted by MeNB 1 and MeNB 2. The user equipment UE measures the first signal quality of the reference signal transmitted by the MeNB 1, and measures the received second signal shield quantity Q1 of the MeNB 2 to transmit the reference signal.

The user equipment UE determines whether a handover condition is satisfied _according to the first signal quality β and the second signal quality _∞ _在一 in a handover detection period T _eselection .

Specifically, in an embodiment similar to the existing mode, the user equipment UE calculates the first indicator at time t ₂ using the above formula (1), and calculates the second time at time t ₅ using the above formula (3). index.

The user equipment UE compares the sizes of the first indicator i? and the second indicator. Since the user equipment UE is closer to the MeNB 2, the second indicator at time t _{5 is} greater than the first indicator. In this case, the user equipment UE initiates a timing of the handover detection period 7^ _£/( ^.„.

During the detection period T _selection , the user equipment UE measures the first signal quality 0_ of the reference signal transmitted by the MeNB 1 in each subframe, and the second signal quality β of the reference signal transmitted by the MeNB 2, After each measurement obtains the signal quality, the user equipment UE calculates the first indicator R _x and the second indicator /? at the moment. The user equipment UE determines whether the second indicator is greater than the first indicator. If greater than, then Continue to judge the next measurement and calculation result; if it is less than, it ends.

After the detection period T _selection, the time t ₆ to time. The user equipment UE is based on the detection period r _{rae /} ^. Greater than the second index continuously "first index? ,, determines the switching condition is satisfied, the user equipment UE belongs directly to the MeNB 1 transmits a handover request, the handover request includes a first signal quality Q proposed _s, _x and Two signal quality related signal quality measurement reports initiate the switching process.

In step S43, the receiver of the base station MeNB 1 receives the handover request sent by the user equipment UE.

Preferably, in step S44, the base station MeNB 1 determines the base station MeNB 2 of the neighboring cell according to the handover request and the topology of the network where the base station is located, and then determines a recheck time window time window T _eck

In step S45, the base station MeNB 1 starts a recheck time window 7; the timing of the ^, during which the MeNB 1 does not send signaling to control the handover or non-handover of the user equipment UE. User equipment UE.

Since the user equipment UE does not receive the signaling sent by the MeNB 1, the user equipment UE continues to measure the first signal quality Q and the second signal quality Q in each frame, and calculates the first indicator and the second indicator R _{n at the} moment, and Is the second indicator greater than the first indicator? ,. If it is greater, the handover request is continued to be sent to the MeNB 1. If it is smaller, the handover request is not sent.

Within the recheck time window T _aeck , it has moved to the cell range under the jurisdiction of the MeNB 2. In this case, the user equipment UE calculates the second index obtained:? Still greater than the first index R _x, it continues to send a handover request to the MeNB 1.

In the review time window Gamma] _{(after ί,} time to time T _7, in step S43, the base station MeNB determination means determines whether the receiver after receiving the first handover request review time windows 7;: ^ after Received a switch request.

Since the user equipment UE is still transmitting the handover request, the judgment means of the MeNB judges that the receiver receives the handover request after the recheck time window elapses. In this case, in step S46, the base station MeNB 1 initiates a handover procedure, and comprehensively determines whether the user equipment UE performs handover, and issues corresponding signaling. The operations performed by the MeNB 1 are all existing in the prior art, and the present invention will not be described herein.

In the above embodiments, preferably, the wider the coverage of the neighboring cells, or the larger the capacity of the neighboring cells, the shorter the time window. Specifically, the time window r corresponding to the MeNB 2 _{(the £} may be shorter than the time window r corresponding to the HeNB 1 ₍ this is because when the user equipment UE moves to a vicinity of a neighboring cell with a larger coverage area, it is more It is possible to be in the neighboring cell for a long time, then the waiting time for repeating detection can be appropriately shortened, and vice versa. When each base station is powered on, the time window corresponding to the base station can be broadcast to each adjacent one. The base station of the cell, so that each base station determines the time window in steps S41 and S44 above. It can be understood that the technical solution is not necessary, and the base station can also use a preset and unified recheck time for each neighboring base station. window.

The second embodiment only needs to improve the existing base station, and does not need to make any changes to the existing user equipment, and has compatibility with the existing user equipment.

The user equipment UE moves through the cell range governed by the macro base station MeNB 1 The cell range governed by the home base station HeNB 1 is returned to the cell range governed by the MeNB 1 and the cell range governed by the MeNB 1 is moved to the cell range governed by the macro base station MeNB 2 as an example. Two aspects are described. It will be understood that the present invention is not limited thereto, and the present invention is equally applicable in the case where the user equipment UE moves from the range under the jurisdiction of a home base station to the range governed by a macro base station, and in other cases. While the invention has been illustrated and described with reference to the particular embodiments

Other variations to the disclosed embodiments can be understood and effected by those skilled in the <RTIgt; In the claims, the <RTIgt; "comprising"</RTI> does not exclude other elements and steps, and the word "a" does not exclude the plural. In the practical application of the invention, a part may perform the functions of the plurality of technical features recited in the claims. Any reference signs in the claims should not be construed as limiting the scope.

Claims

Claim

CLAIMS 1. A method for initiating a cell handover in a user equipment, the user equipment measuring a first signal quality of a signal from a base station of a cell to which it belongs and a second signal quality of a signal from a base station of a neighboring cell, the method comprising The following steps:

- determining whether all of the replacement conditions are satisfied based on the first and second signal qualities within a handover detection period;

- when the switching condition is satisfied, delaying a switching recheck time window, and determining whether a rechecking condition is satisfied according to the first and second signal shields after the time window;

- When the recheck condition is satisfied, a handover request is sent to the base station of the cell to which it belongs, the handover request including a signal quality measurement report related to the first and second signal qualities.

2. The method according to claim 1, wherein the determining step comprises the following steps:

- Determine the first indicator R for the time period using the following formula:

R _x = Q w + Q _hy , , where Q is the first signal quality at each moment in the time period, β is a hysteresis coefficient;

- Use the following formula to determine the second indicator for the time period:

R _n = Q _m , where Q is the second signal quality at each moment in the time period, Q _nffic is an offset coefficient for controlling frequency or cell characteristics; - the switching condition is: at the time In the segment, the second indicator is continuously greater than the first indicator

The method according to claim 1 or 2, wherein the determining step comprises the following steps:

- Determine the first indicator R _x after the time window has elapsed using the following formula:

R _s = + a,, , where is the first signal quality after the time window is over, which is a hysteresis coefficient;

- Use the second indicator after the time window described in the following formula ^ :

R _n = Q + , where Q is the second signal after the time window has elapsed Quality, a biasing factor used to control frequency or cell characteristics;

- the re-inspection condition is: the second index ^ after the time window is greater than the first index R,.

4. Method according to claim 1, characterized in that the method is used for handover between heterogeneous network cells under the LTE-A standard.

5. A method for initiating cell handover processing for a user equipment under control in a base station, the user equipment measuring a first signal quality of a signal from the base station and a second signal from a base station of a neighboring cell Signal quality, the method includes the following steps:

Receiving a first handover request sent by the user equipment, the first handover request being sent by the user equipment according to the first and second signal qualities in a handover detection period determining that all the conditions are satisfied;

- delaying a handover recheck time window, determining whether the second handover request sent by the user equipment is still received after the time window expires, the second handover request being first and second by the user equipment according to the time period Signal quality is determined to be sent when a handover condition is satisfied;

- When receiving the second handover request, performing cell handover processing of the user equipment to the neighboring cell.

The method according to claim 5, wherein the method further comprises the following steps before the determining step:

Determining information of the neighboring cell according to the first handover request and a topology of the network where the base station is located;

- determining the time window based on the information of the neighboring cell.

The method according to claim 6, wherein the coverage area of the neighboring cell is wider, or the capacity of the neighboring cell is larger, and the time window is shorter.

8. Method according to claim 5, characterized in that the method is used to control the switching between heterogeneous network cells under the LTE-A standard.

9. A device for initiating a cell handover in a user equipment, the user equipment measuring a first signal quality of a signal from a base station of a neighboring cell and a second signal shield of a signal from a base station of a neighboring cell, the device Includes:

- judging means for using the first and second signals according to a switching detection period Quality, judge whether a switching condition is satisfied;

Determining means for determining whether a recheck condition is satisfied according to the first and second signal qualities after a switching recheck time window is satisfied when the switching condition is satisfied;

- a transmitter, configured to send a handover request to the base station of the cell to which the re-inspection condition is satisfied, the handover request including a signal quality measurement report related to the first and second signal shields.

A user equipment, comprising: means for initiating a cell handover in a user equipment according to claim 9.

11. A device in a base station for initiating cell handover processing for a user equipment under control, the user equipment measuring a first signal quality of a signal from a base station and a second signal from a base station of a neighboring cell Signal quality, the device includes:

a receiver, configured to receive a first handover request and a second handover request sent by the user equipment, where the first handover request is determined by the user equipment according to the first and second signal qualities in a handover detection period Transmitting, the second handover request is sent by the user equipment according to the first and second signal quality after the time period to determine that a handover condition is satisfied;

a determining device, configured to determine whether the receiver receives the second switching request after a switching recheck time window after receiving the first switching request;

a processor, configured to perform cell handover processing of the user equipment to the neighboring cell when the receiver receives the second handover request.

A base station, comprising: means for initiating cell handover processing for a user equipment under control in a base station according to claim 11.