KR100276722B1 - Grouping and Ungrouping of Micro-Cells Using Dividers in Cellular Systems - Google Patents

Abstract

Disclosed are a method of grouping and ungrouping micro-cells using a distributor in a cellular system. When the service area of the base station is divided into a plurality of micro-cells each having a unique pilot signal, the base station uses a splitter that connects a path between the sector interface unit and the transceiver and the micro-cell to be grouped with the pilot signal of the reference micro-cell. Through their transceivers and relay stations. The micro-cells to be grouped then all have the same pilot signal, resulting in one omni-cell. Since the mobile phone recognizes the omni-cell as one cell, handoff between cells does not occur while moving in the omni-cell.

In addition, when the micro-cells of the base station service area are grouped using the reference pilot signal, the base station transmits a unique pilot signal corresponding to each micro-cell through the transceiver and the relay station of each micro-cell. Therefore, the grouped micro-cells each have a unique pilot signal. If the omni-cell has too many subscribers, the base station can accommodate many subscribers by ungrouping the omni-cell.

Description

Grouping and Ungrouping of Micro-Cells Using Dividers in Cellular Systems

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cellular mobile telecommunication system. In particular, a splitter is additionally installed in a base station of a micro-cell structure, and then a plurality of micro-cells are used by using a splitter. In a method for grouping and ungrouping micro-cells using a divider in a cellular system, grouping the groups into one omni-cell, and ungrouping the omni-cell into the original micro-cell. It is about.

The cellular mobile communication system divides the entire service area into a plurality of base station areas and constitutes cells, which are small service areas, and centrally controls these base stations to the mobile switching center so that subscribers can continue communication while moving between cells. do. In cellular systems, a handoff function allows a call to continue when the mobile phone leaves the area of one base station and enters the area of another base station.

1 illustrates a schematic diagram of a cellular system using Code Division Multiple Access (CDMA) technology. As shown, a base station transceiver subsystem (BTS) 20, 30, 40 that provides a mobile communication service to a mobile telephone (MT) 10, and a plurality of base stations are public switched telephones. It consists of a Mobile Switching Center (MSC) 50 that connects to a Public Switched Telephone Network (PSTN) 60.

Cellular mobile communication systems improve the efficiency of use of scarce frequencies, allowing more users to use them. The concept introduced to further increase the frequency efficiency is a cell division technique, and one of such cell division techniques is a micro-cell. The micro-cell means an area that can be serviced by a relay station connected to a base station, and one base station may be connected to a plurality of relay stations by using a cable or an optical cable. Therefore, one cell is composed of a plurality of micro-cells.

Since the radius of a micro-cell is about 200 m and much smaller than a normal cell, the micro-cellular system can divide the same area into more areas (micro-cells). Therefore, the micro-cellular system can increase the frequency capacity compared to the general cellular system, but instead, the handoff between micro-cells increases, which causes unnecessary call processing from the standpoint of the base station.

The base station must perform a stable handoff so that the call of the mobile telephone traveling between the micro-cells is not disconnected. The mobile phone uses a pilot signal to recognize that it has entered a different micro-cell. The pilot signal is an identification signal for distinguishing different service areas (or micro-cells) in a cellular system.

Handoff requires a lot of work, which places a heavy load on the base station. Furthermore, even when operating a base station designed with a micro-cell structure to increase the frequency utilization efficiency, even if the number of subscribers is reduced and no cell division is required, the base station is still maintained because of the micro-cell structure. Handoffs between micro-cells frequently occur.

In the prior art operating as described above, many unnecessary handoffs occur when the mobile phone moves between micro-cells, and this handoff causes a call breakup or a base station overload, which degrades the call quality and There was a problem of reducing the efficiency.

Accordingly, an object of the present invention, which was devised to solve the problems of the prior art operating as described above, is that in a base station having a structure of a micro-cell for distributing signals to a plurality of relay stations, the signal of one micro-cell is changed to another. A method of grouping micro-cells using a splitter in a cellular system is provided in which a splitter connecting to a micro-cell is mounted on a base station and the plurality of micro-cells are grouped into one omni-cell using the splitter. It aims to do it.

Another object of the present invention is to provide a method of ungrouping micro-cells using a divider in a cellular system, which ungroups omni-cells into a plurality of micro-cells using a distributor mounted at a base station. It is done.

Other objects and advantages of the present invention will become more apparent from the following detailed description of the invention and the accompanying drawings.

1 is a schematic diagram of a cellular system employing code division multiple access (CDMA) technology.

2 is an embodiment of a micro-cellular system configuration to which the present invention is applied.

3 is an embodiment of a micro-cell base station configuration using a distributor according to the present invention;

4 is a diagram for one embodiment of a connection between a sector interface unit, a distributor, and a transceiver according to the present invention;

Figure 5 is an embodiment of the internal configuration of the dispenser according to the present invention.

6 is a flowchart illustrating a method of grouping micro-cells in accordance with the present invention.

7 is a flowchart illustrating a method for ungrouping micro-cells in accordance with the present invention.

<Explanation of symbols for the main parts of the drawings>

10: mobile phone 20, 30, 40: base station

50: mobile switching center 60: public switched telephone network

70,80,90: Relay station 102,104,106: Channel card

112, 114, 116: summer 122, 124, 126: sector interface unit

130,131,132,133: Splitter

141,142,143,144,145,146,147,148,149: transceiver

1,2: Internal path of the distributor 3,4: Switch for switching

A preferred embodiment of the method of grouping micro-cells using a divider in the cellular system according to the present invention, which is designed to achieve the above object, consists of a plurality of micro-cells each having a unique pilot signal, A cellular system comprising a base station providing a mobile communication service to a mobile telephone in a cell,

Mounting, by the base station, a distributor connecting the path between the transceiver and the sector interface for all micro-cells for grouping of the micro-cells;

The pilot signal (first pilot signal) of the reference micro-cell (first micro-cell) on which the base station is to be grouped, through the transceiver and the relay station of the micro-cell (second micro-cell) to be grouped by the base station Sending a;

A first mobile phone that detects a pilot signal (second pilot signal) of a second micro-cell transmitted through a transceiver and a relay station of a second micro-cell is transmitted through a transceiver and a relay station of a second micro-cell. Detecting a new pilot signal and reporting the detection of the first pilot signal to the base station;

Allocating a traffic channel corresponding to the first pilot signal to the mobile phone by the base station that has received the detection of the first pilot signal;

The mobile telephone recognizing the allocation of the traffic channel, connecting the channel simultaneously with the traffic channel corresponding to the second pilot signal and the traffic channel corresponding to the first pilot signal, and communicating with the base station through two channels;

The base station communicating with the mobile phone over two channels, gradually decreasing the strength of the second pilot signal transmitted through the transceiver and the relay station of the second micro-cell;

Detecting, by the mobile telephone communicating with the base station via the two channels, a decrease in the strength of the second pilot signal and reporting a change in strength of the pilot signal to the base station;

Receiving a change in the strength of the pilot signal by the base station, instructing the mobile phone to disconnect the traffic channel corresponding to the second pilot signal and to maintain only the traffic channel corresponding to the first pilot signal; And

The mobile telephone, instructed by the base station, disconnects the traffic channel corresponding to the second pilot signal and communicates with the base station using only the traffic channel corresponding to the first pilot signal.

A preferred embodiment of the method of ungrouping micro-cells using a divider in the cellular system according to the present invention, which was devised to achieve the above object, is a reference micro-cell (first micro-cell) sent out through the dispenser. A cellular system comprising a base station providing a mobile communication service to a mobile telephone in an omni-cell grouped using a first pilot signal of

Transmitting, by the base station, a unique pilot signal (second pilot signal) through a transceiver and a relay station of a second micro-cell constituting the grouped omni-cell;

The mobile telephone detecting the first pilot signal transmitted through the transceiver of the second micro-cell and the relay station newly detects the second pilot signal transmitted through the transceiver and relay station of the second micro-cell, and transmits the signal to the base station. Reporting the detection of two pilot signals;

Allocating a traffic channel corresponding to the second pilot signal to the mobile phone by the base station, which has received the detection of the second pilot signal;

The mobile telephone recognizing the allocation of the traffic channel, connecting the channel simultaneously with the traffic channel corresponding to the first pilot signal and the traffic channel corresponding to the first pilot signal, and communicating with the base station through two channels;

The base station communicating with the mobile phone over two channels, gradually decreasing the strength of the first pilot signal transmitted through the transceiver and the relay station of the second micro-cell;

Detecting, by the mobile telephone communicating with the base station via the two channels, a decrease in the strength of the first pilot signal and reporting a change in the strength of the pilot signal to the base station;

Receiving a change in the strength of the pilot signal by the base station, instructing the mobile phone to disconnect the traffic channel corresponding to the first pilot signal and to maintain only the traffic channel corresponding to the second pilot signal; And

The mobile telephone commanded by the base station disconnects the traffic channel corresponding to the first pilot signal and communicates with the base station using only the traffic channel corresponding to the second pilot signal.

In the following description of the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted. Terms to be described later are terms defined in consideration of functions in the present invention, and may be changed according to intentions or customs of users or operators. Therefore, the definition should be made based on the contents throughout the specification. Hereinafter, with reference to the accompanying drawings will be described in detail the operating principle of the preferred embodiment of the present invention.

The present invention provides a method in which multiple micro-cells having different pilot signals all have the same pilot signal. If multiple micro-cells all have the same pilot signal, the mobile phone recognizes multiple micro-cells with the same pilot signal as one cell. Therefore, even if a mobile phone moves between the micro-cells, no handoff occurs, and the mobile phone can be provided with a stable communication service like a mobile phone moving in one cell.

In a system using code division multiple access technology, each micro-cell is separated from each other using a PN offset of a unique Pseudo Noise (PN) code, so that the base station transmits a pilot signal to a mobile phone. Send information about PN offset in. The mobile phone can analyze the sensed pilot signal to determine which micro-cell it is located in and request a handoff.

In order to make multiple micro-cells that had a unique PN offset all have the same PN offset, the present invention uses a divider. Hereinafter, with reference to the accompanying drawings will be described in detail the operating principle of the preferred embodiment of the present invention.

2 is a block diagram of a micro-cellular system to which the present invention is applied, and as shown, the base station 20 and the first to third relay stations 70 and 80 connected to the base station 20 through an optical cable. 90).

A base station using a technique using a code division multiple access technique spreads a signal transmitted from a mobile switching center by multiplying a long code and a Walsh code, and then distinguishes each micro-cell from the spread signal. Multiply by the unique signal for the transmission through the transceiver to the corresponding relay station. The channel card of the base station includes four, eight, or sixteen channel elements. Since each channel element has three paths, the channel card combines the output of each channel element for each path and delivers the signal to the antenna.

The base station of the micro-cellular structure combines three paths output from each channel card and delivers them to a plurality of relay stations. Therefore, the present invention uses a splitter that combines the paths of three signals output from each channel card of the base station, thereby changing the pilot signal (PN offset) of other micro-cells based on the desired micro-cell. You can operate a cell as if it were a single cell.

Figure 3 illustrates one embodiment of a micro-cell base station configuration with a distributor according to the present invention.

As shown in the drawing, the first to third signals are composed of four channel elements, three modulators (Mods) and three digital to analog converters (D / A) to generate signals corresponding to three paths. Third channel card (102) (104) (106); First to third summers 112, 114, and 116 for summing signals of respective paths transmitted from each channel card; First to third sector interface units 122, 124 and 126 for generating signals transmitted from the adder as signals for each micro-cell, and a divider for connecting signals transmitted from each sector interface unit to other micro-cells ( 130); First to ninth transceivers 141, 142, 143, 144 that convert signals transmitted from the splitter into radio frequency signals (RF signals) and transmit them to each relay station through an optical cable. 145, 146, 147, 148, 149.

The distributor 130 is configured to connect a signal of one micro-cell to a transceiver of another micro-cell. FIG. 4 illustrates in detail the connection between the sector interface unit 126 and the distributor 130 and the transceiver according to the present invention. As shown, the third sector interface unit 126 outputs three signals Tx # 7 and Tx # 8 and Tx # 9 corresponding to three micro-cells. The Tx # 7 is divided into three signals Tx '# 7 by the seventh splitter 137 and transmitted to the seventh transceiver 147, the eighth transceiver 148, and the ninth transceiver 149, respectively. Like Tx # 7, Tx # 1 to Tx # 9 are also transmitted to the first transceiver 141 through the ninth transceiver 149 by the distributor. Divider 130 therefore allows the transceiver to be coupled with the signals of all micro-cells.

Since the distributor connects the sector interface unit and the transceiver, an abnormality in the internal path may have a fatal effect on the provision of the mobile communication service. Therefore, as shown in Fig. 5, the inside of the distributor 137 is duplexed into two paths (1) and (2), and if an abnormality occurs in one path, the switch (3) and (4) is used to switch to another path. This ensures that the normal path is always used.

A base station including a distributor configured as described above may connect a signal of one micro-cell to another desired micro-cell. Therefore, in order to group a plurality of micro-cells into one omni-cell using a base station having the above configuration, a micro-cell that is a grouping standard is selected, and a pilot signal (PN offset) of another micro-cell is referenced. Convert to a micro-cell pilot signal. The conversion can be performed by applying a handoff between micro-cells.

6 is a flowchart illustrating a method of grouping micro-cells according to the present invention. Hereinafter, a grouping method according to the present invention will be described with reference to FIG. 6.

First, a reference micro-cell, which is a reference for grouping, is selected. Herein, the operation of the present invention will be described using an embodiment of grouping a second micro-cell into a first micro-cell based on the first micro-cell. do. However, the reference micro-cell may be any micro-cell that can be serviced by one base station.

In step s110, the base station of the micro-cell structure mounts a divider for grouping the micro-cells, and selects a reference micro-cell that is the basis of the grouping. Given that the first micro-cell selected as the reference for grouping has a first pilot signal, and the other micro-cell to be grouped (second micro-cell) has a second pilot signal, in step s120, the base station A splitter is used to send the pilot signal of the first micro-cell through the transceiver and the relay station of the second micro-cells. Since the pilot signals all have different PN offsets, they can be distinguished from each other.

The first pilot signal is sent out through the transceivers of all the micro-cells to be grouped (eg the second micro-cell) to the relay station antennas of the micro-cells to be grouped. At this time, the transceiver of the micro-cell to be grouped transmits only the signal for the micro-cell to be grouped and the signal for the reference micro-cell to the relay station. That is, the second splitter connected to the transceiver of the second micro-cell blocks the signal of the other micro-cell and transfers only the signal of the first micro-cell, which is the reference for grouping with the signal of the second micro-cell, to the second transceiver. do. By the operation of the distributor as described above, the transceiver and the relay station of the second micro-cell simultaneously transmit the first pilot signal and the second pilot signal.

In step s130, the mobile phone, which has detected the pilot signal (second pilot signal) of the corresponding micro-cell in the second micro-cell, newly detects the first pilot signal transmitted through the antenna of the same relay station, and the base station. Report a new pilot signal.

In step s140, the base station, which has received the detection of the first pilot signal from the mobile phone, sets the idle channel as a traffic channel having the first pilot signal, assigns the set traffic channel to the mobile phone, and then sends the mobile phone to the mobile phone. Signals that a traffic channel has been allocated. Then, in step s150, the mobile phone connects the channel simultaneously with the traffic channel of the second pilot signal originally communicating with the traffic channel of the newly allocated first pilot signal, and communicates with the base station through the two channels.

For grouping the micro-cells, in step S160, the base station gradually decreases the strength of the second pilot signal transmitted through the transceiver and the relay station of the second micro-cell. In step s170, the mobile telephone in the micro-cell to be grouped senses a decrease in the second pilot strength and reports the decrease in pilot strength to the base station. If the strength of the second pilot signal detected by the mobile phone decreases below a certain level, in step S180, the base station disconnects the traffic channel of the second pilot signal to the mobile phone, and only the traffic channel of the first pilot signal. Command to keep

In step S190, the mobile phone receiving the command of the base station stops receiving the second pilot signal to disconnect the traffic channel of the second pilot signal, and communicates with the base station using only the traffic channel of the first pilot signal.

When the above process is repeated for each micro-cell to be grouped, each micro-cell of the base station having different pilot signals has the same pilot signal (pilot signal of the reference micro-cell). Therefore, no handoff occurs even if the mobile phone moves between grouped micro-cells. In this case, the base station may select as many micro-cells as desired for grouping, and connect the pilot signals of the reference micro-cells to the transceivers of the micro-cells to be grouped. Therefore, the grouping method according to the present invention can operate as an omni-cell by grouping a desired number of micro-cells.

Since the micro-cell is divided to provide more subscribers, the grouped omni-cell structure of base stations cannot provide as many subscribers as the base station of the micro-cell structure. Therefore, if the number of subscribers located in the omni-cell increases and the omni-cell structure cannot provide services to all subscribers, the base station ungroups the omni-cell. Therefore, a method of ungrouping omni-cells according to the present invention will be described.

7 is a flowchart illustrating a method for ungrouping micro-cells according to the present invention. Hereinafter, the ungrouping method according to the present invention will be described with reference to FIG. 7.

The base station transmits pilot signals (first pilot signals) of the reference micro-cells (first micro-cells) through transceivers and relay stations of all grouped micro-cells (second micro-cells). Therefore, the grouped micro-cell transceiver and the relay station are transmitting only the first pilot signal, and in step s210, the mobile telephone in the second micro-cell uses the splitter through the transceiver and the relay station of the second micro-cell. The first pilot signal of the transmitted reference micro-cell (first micro-cell) is used to communicate with the base station.

For ungrouping of the grouped omni-cells, in step 220 the base station transmits a unique pilot signal (second pilot signal) corresponding to that micro-cell before being grouped through the transceiver and the relay station of the second micro-cell. Start sending. The transceiver of the grouped second micro-cell and the relay station then transmit the first pilot signal and the second pilot signal simultaneously.

In step s230, the mobile phone in communication using the first pilot signal in the second micro-cell newly detects the second pilot signal and reports to the base station that it has detected a new pilot signal.

In step s240, the base station that has received the detection of the new pilot signal from the mobile phone sets the idle channel to the traffic channel corresponding to the second pilot signal, assigns the set traffic channel to the mobile phone, and then sends the mobile phone to the mobile phone. Signals that a traffic channel has been allocated. Then, in step S250, the mobile phone simultaneously connects the channel with the traffic channel of the first pilot signal that was originally communicating with the traffic channel of the newly detected second pilot signal, and communicates with the base station through the two channels.

To remove the grouped micro-cells, the base station gradually decreases the strength of the first pilot signal transmitted through the transceiver and the relay station of the second micro-cell in step s260.

In step s270, the mobile telephone in the second micro-cell senses the strength reduction of the first pilot signal and reports the change in pilot strength to the base station. If the strength of the first pilot signal detected by the mobile phone decreases below a certain level, in step s280, the base station disconnects the traffic channel of the first pilot signal to the mobile phone, and only the traffic channel of the second pilot signal. Command to keep

In step s290, the mobile phone disconnects the traffic channel of the first pilot signal and communicates with the base station using only the second pilot signal. In this step, since the base station transmits only the second pilot signal through the transceiver of the second micro-cell and the relay station, the distributor of the base station blocks the first pilot signal connected to the transceiver of the second micro-cell.

Repeating the above ungrouping method for the grouped micro-cells, the grouped micro-cells only transmit pilot signals each having a unique PN offset, so that the mobile phone can distinguish each micro-cell. do.

The present invention can be variously modified and can take various forms and only the specific embodiments thereof are described in the detailed description of the invention. It is to be understood, however, that the present invention is not limited to the specific forms mentioned in the detailed description of the invention, but rather includes all modifications, equivalents, and substitutions within the spirit and scope of the invention as defined by the appended claims. It should be understood to do.

In the present invention operating as described in detail above, the effects obtained by the representative ones of the disclosed inventions will be briefly described as follows.

The grouping method according to the present invention can reduce the load of the base station by suppressing the incidence of handoff, which occurs particularly in a micro-cell environment, and provide a subscriber with high quality service without disconnection of calls. By increasing the actual distance between the co-channel group to improve the signal interference ratio (Signal Interference Ratio), and also has the effect that each relay station can act as a distributed antenna to obtain spatial diversity.

In addition, the ungrouping method according to the present invention, when the number of subscribers in the grouped omni-cell increases to increase the frequency capacity of the base station, to return to the original micro-cell structure, and facilitates the location of the subscribers There is an effect that can be grasped.

Claims (8)

A cellular system comprising a plurality of micro-cells each having a unique pilot signal, the cellular system including a base station providing a mobile communication service to a mobile telephone in the micro-cell, A base station connecting a divider between the transceiver and the sector interface for all micro-cells, and selecting a reference micro-cell (first micro-cell) as a reference for grouping; Transmitting, by the base station, a pilot signal (first pilot signal) of the first micro-cell to a relay station and a transceiver station of the micro-cell (second micro-cell) to be grouped using the distributor; The mobile telephone communicating with the transceiver of the second micro-cell using the pilot signal (second pilot signal) of the second micro-cell transmitted through the relay station is transmitted through the transceiver of the second micro-cell and the relay station. Newly detecting the first pilot signal and reporting the detection of the first pilot signal to the base station; Allocating a traffic channel corresponding to the first pilot signal to the mobile phone by the base station that has received the detection of the first pilot signal; The mobile telephone recognizing the allocation of the traffic channel, connecting the channel simultaneously with the traffic channel corresponding to the second pilot signal and the traffic channel corresponding to the first pilot signal, and communicating with the base station through two channels; The base station communicating with the mobile phone over two channels, gradually decreasing the strength of the second pilot signal transmitted through the transceiver and the relay station of the second micro-cell; Detecting, by the mobile telephone communicating with the base station via the two channels, a decrease in the strength of the second pilot signal and reporting a change in strength of the pilot signal to the base station; Receiving a change in the strength of the pilot signal by the base station, instructing the mobile phone to disconnect the traffic channel corresponding to the second pilot signal and to maintain only the traffic channel corresponding to the first pilot signal; And The mobile telephone commanded by the base station disconnects the traffic channel corresponding to the second pilot signal and communicates with the base station using only the traffic channel corresponding to the first pilot signal. Method of grouping micro-cells using The method of claim 1, wherein the transmitting of the first pilot signal through a transceiver of a second micro-cell comprises: A method of grouping micro-cells using a divider in a cellular system, wherein a transceiver of a second micro-cell and a relay station transmit a second pilot signal and a first pilot signal simultaneously. The method of claim 1, wherein the command to maintain only the traffic channel corresponding to the first pilot signal, The base station received the change in the strength of the pilot signal, when the strength of the second pilot signal decreases below a certain level, instructs to maintain only the traffic channel corresponding to the first pilot signal of the micro-cell using the splitter in the cellular system Grouping method. The method of claim 1, wherein the mobile telephone communicates with a base station using only a traffic channel corresponding to a first pilot signal. A method of grouping micro-cells using a divider in a cellular system, wherein both the reference micro-cell and the micro-cells to be grouped will have the same pilot signal (first pilot signal). A cellular system comprising a plurality of micro-cells each having a unique pilot signal, the cellular system including a base station providing a mobile communication service to a mobile telephone in the micro-cell, The first pilot of the reference micro-cell (first micro-cell), which is transmitted through the transceiver and the relay station of the second micro-cell, by the mobile telephone in the second micro-cell constituting the grouped omni-cell Communicating with a base station using a signal; Transmitting, by the base station, a unique pilot signal (second pilot signal) through the transceiver of the second micro-cell and the relay station; Detecting, by the mobile phone communicating using the first pilot signal, a second pilot signal transmitted through a relay station and a transceiver of the second micro-cell, and reporting the detection of the second pilot signal to the base station; Allocating a traffic channel corresponding to the second pilot signal to the mobile phone by the base station, which has received the detection of the second pilot signal; The mobile telephone recognizing the allocation of the traffic channel, connecting the channel simultaneously with the traffic channel corresponding to the first pilot signal and the traffic channel corresponding to the first pilot signal, and communicating with the base station through the two traffic channels; The base station communicating with the mobile phone over two channels, gradually decreasing the strength of the first pilot signal transmitted through the transceiver and the relay station of the second micro-cell; Detecting, by the mobile telephone communicating with the base station via the two channels, a decrease in the strength of the first pilot signal and reporting a change in the strength of the pilot signal to the base station; Receiving a change in the strength of the pilot signal by the base station, instructing the mobile phone to disconnect the traffic channel corresponding to the first pilot signal and to maintain only the traffic channel corresponding to the second pilot signal; And A cellular telephone using a splitter in a cellular system, the method comprising the steps of the mobile telephone commanded by the base station to disconnect the traffic channel corresponding to the first pilot signal and to communicate with the base station using only the traffic channel corresponding to the second pilot signal. How to ungroup cells. The method of claim 1, wherein transmitting the second pilot signal through the transceiver and the relay station of the second micro-cell, A method of ungrouping micro-cells using a divider in a cellular system, wherein the transceiver and the relay station of the micro-cells to be grouped simultaneously transmit a second pilot signal and a first pilot signal. The method of claim 1, wherein the step of instructing to maintain only the traffic channel of the second pilot signal is: Ungrouping of micro-cells using a splitter in a cellular system instructing the base station that is reported to change the strength of the pilot signal to maintain only the traffic channel of the second pilot signal when the strength of the first pilot signal decreases below a certain level. Way. The method of claim 1, wherein communicating with a base station using only a traffic channel corresponding to the second pilot signal, A method of ungrouping a micro-cell using a divider in a cellular system, wherein the reference micro-cell and the grouped micro-cell each have a unique pilot signal.