KR100529761B1 - Method of setting up a boundary between the coverage of each generation in mobile communication system - Google Patents

Abstract

The present invention relates to a method for setting an intergenerational service area in a mobile communication system, wherein a second generation (or 2.5 generation) base station in an intergenerational boundary area transmits radio waves of the same frequency band as that transmitted from an adjacent third generation base station. By effectively blocking the radio waves from the third generation base station, the DBDM terminal can smoothly transition between generations in the border area, thereby minimizing the quality defect caused by the ping-pong phenomenon.

Description

METHOOD OF SETTING UP A BOUNDARY BETWEEN THE COVERAGE OF EACH GENERATION IN MOBILE COMMUNICATION SYSTEM}

The present invention relates to a method for setting an intergenerational service area in a mobile communication system, and more particularly, to enable a dual band dual mode (DBDM) terminal to smoothly transition between generations in a boundary area between a third generation and a second generation mobile communication system. The present invention relates to a method for establishing a service area between generations in which coverage is adjusted to distinguish service area boundaries.

As is well known, the WCDMA (Wideband Code Division Multiple Access) system, the third generation mobile phone service, and the IS-95A / B, the second generation mobile phone service, and the CDMA2000 1X system, the 2.5th generation mobile phone service, have different frequency bands as well as technical methods. Do.

In addition, since the initial WCDMA system will start service in an area smaller than the existing 2G and 2.5G mobile phone service areas, WCDMA terminals move to 2G (or 2.5G) to provide seamless services to WCDMA subscribers. It should be DBDM (Dual Band Dual Mode) method that supports phone service function together.

Accordingly, WCDMA subscribers access 3G mobile telephone networks in overlay areas where 3G and 2G (or 2.5G) mobile telephone networks are established, and 2G ( Or 2.5 generation) can access mobile phone network.

In this case, an area in which the WCDMA frequency has a weak electric field may occur in the third generation overlay area and the second generation (or 2.5 generation) single service area at the boundary.

In such weak field, the WCDMA terminal has a problem of deteriorating the quality of mobile phone service because it is difficult to acquire either the second generation (or 2.5 generation) system or the third generation system. This phenomenon is called a ping-pong phenomenon.

On the other hand, it is possible to prevent some of the weak electric field formation in the second generation (or 2.5 generations) region by adjusting the transmission power of the third generation base station in the overlay region, but it is not an effective method because the base station coverage varies according to the terrain and the generated call. none.

The present invention has been proposed to solve such a conventional problem, minimizing the quality defect caused by the ping-pong phenomenon by allowing the DBDM terminal to smoothly transition between generations in the boundary area between the third and second generation mobile communication systems. Its purpose is to.

In the mobile communication system according to the present invention for realizing the above object, the generation generation service area setting method includes a WCDMA overlay area and a CDMA exclusive service area, which support both a WCDMA mobile phone service function and a CDMA mobile phone service function. In a method for setting an intergenerational service area in a mobile communication system employing a DBDM terminal, a CDMA base station generates a WCDMA pseudo frequency in which a pseudo code is included in an overhead channel while transmitting a CDMA frequency while covering the CDMA single service area. Transmitting to the boundary area of the CDMA exclusive service area with the WCDMA overlay area; transmitting, at a WCDMA base station, a WCDMA frequency with coverage of the WCDMA overlay service area; and the CDMA single service area and the WCDMA overlay. Boundaries with Service Areas The DBDM terminal is located in the station on the basis of the pseudo code contained in the overhead channel of the WCDMA frequency identification physician in that the boundary area is the CDMA service region alone by a step of access to the CDMA network.

There may be a plurality of embodiments of the present invention. Hereinafter, preferred embodiments will be described in detail with reference to the accompanying drawings. This embodiment allows for a better understanding of the objects, features and advantages of the present invention.

1 is a configuration diagram of a mobile communication system to which the method for setting an intergenerational service area according to the present invention can be applied.

In the figure, reference numeral 110 is a CDMA Base Station Controller (CDMA BSC), 115 is a CDMA Base Station Transceiver Subsystem (CDMA BTS), 120 is a WCDMA Base Station Controller (WCDMA BSC), and 125 is a WCDMA. The WCDMA service area including the WCDMA base station controller 120 and the WCDMA base station 125 is a base station (WCDMA BTS), the system for the CDMA service for the convenience of the WCDMA overlay area or the display of the existing CDMA service is provided The drawing display is omitted. A denotes a region in which the WCDMA frequency has a weak electric field, which is a CDMA exclusive service area at the boundary of the WCDMA overlay area.

The CDMA base station 115 connects a DBDM terminal (not shown) to the CDMA base station controller 110, communicates wirelessly with the DBDM terminal, and communicates with the CDMA base station controller 110 by wire. Perform the function. In addition, the CDMA base station 115, which transmits a CDMA frequency covering the CDMA exclusive service area, and particularly the CDMA exclusive service area at the boundary with the WCDMA overlay area, transmits a pseudo signal to the overhead channel so as to identify the CDMA exclusive service area. The WCDMA pseudo frequency including the code is transmitted with the CDMA single service area as the coverage.

The CDMA base station controller 110 connects the CDMA base station 115 to a CDMA switchboard (not shown) to coordinate the connection between the CDMA base stations 115, support a plurality of CDMA base stations 115, and support the CDMA base station 115. ) And a signal processing function for communication between CDMA exchange periods.

The WCDMA base station 125 connects a DBDM terminal (not shown) to the WCDMA base station controller 120, wirelessly communicates with the DBDM terminal, and performs wired / wireless conversion with the WCDMA base station controller 120 by wire. Perform the function. In addition, it transmits a WCDMA frequency covering the WCDMA overlay service area.

The WCDMA base station controller 120 connects the WCDMA base station 125 to a WCDMA switchboard (not shown) to coordinate the connection between the WCDMA base stations 125, supports a plurality of WCDMA base stations 125, and supports the WCDMA base station 125 ) And a signal processing function for communication during the WCDMA switching period.

In the above mobile communication system, the DBDM terminal located in the boundary area A between the WCDMA overlay zone and the CDMA exclusive service zone has a weak field formed by the WCDMA frequency transmitted from the WCDMA base station 125. Based on the pseudo code included in the overhead channel of the WCDMA pseudo-frequency transmitted by the WCDMA, the corresponding area A is identified as a CDMA exclusive service area, and it is connected to the CDMA network, thereby ping-pong in the boundary area A. ) The phenomenon does not occur.

On the other hand, when the WCDMA base station 125 in the WCDMA overlay area uses a plurality of frequencies, the CDMA base station 115 in the CDMA single service area must also transmit the same number of WCDMA pseudo frequencies. In this case, it is preferable to generate a plurality of WCDMA pseudo frequencies from a single pseudo frequency generator by using a hopping method, and adjust the coverage for each individual frequency by transmitting the generated plurality of WCDMA pseudo frequencies. That is, by time-division multiplexing and transmitting each frequency, all the ping-pong phenomena by a plurality of WCDMA frequencies are prevented.

Hereinafter, referring to FIG. 2, a process of accessing a DBDM terminal located in a WCDMA overlay zone and a border area A to a CDMA network or a WCDMA network will be described in detail.

First, the DBDM terminal receives the CDMA frequency transmitted by the CDMA base station 115 and the WCDMA frequency transmitted by the WCDMA base station 125 (S201). At this time, if the region where the DBDM terminal is located is the CDMA exclusive service area and only the CDMA frequency is received, the DBDM terminal will naturally access the CDMA network, that is, the CDMA switch through the CDMA base station 115.

When the WCDMA frequency is received, the DBDM terminal analyzes the WCDMA frequency to determine whether a pseudo code exists in the overhead channel (S203 to S205).

Here, the DBDM terminal located in the WCDMA overlay service area cannot find a pseudo code in the overhead channel of the WCDMA frequency, thereby accessing the WCDMA network, that is, accessing the WCDMA switch through the WCDMA base station 125 (S209).

However, a DBDM terminal located in the boundary area (A) between the WCDMA overlay area and the CDMA exclusive service area finds a pseudo code in an overhead channel of the WCDMA frequency, thereby recognizing that the boundary area (A) is the CDMA exclusive service area. A network is connected, that is, a CDMA switch is connected via the CDMA base station 115 (S207).

In addition, in the boundary area (A) between the WCDMA overlay area and the CDMA exclusive service area, the strong field formed by the WCDMA pseudo-frequency pushes out the weak field formed by the WCDMA frequency, thereby minimizing the weak field forming area of the WCDMA frequency. It has an effect.

In the above description, but limited to one embodiment of the present invention, it is obvious that the technology of the present invention can be easily modified by those skilled in the art. Such modified embodiments should be included in the technical spirit described in the claims of the present invention.

As described above, the present invention transmits radio waves in the same frequency band as the frequency transmitted by the adjacent third generation base station from the second generation (or 2.5 generation) base station in the inter-generational boundary area to effectively block the radio waves from the adjacent third generation base station. As a result, the DBDM terminal can smoothly transfer services between generations in the border area, thereby minimizing the quality defect caused by the ping-pong phenomenon.

In addition, since the WCDMA overlay region can be flexibly set by adjusting the transmit power of the WCDMA pseudo-frequency in the second generation base station, it is possible to increase the network investment efficiency in terms of mobile operators. That is, when the operator sets the overlay boundary area, the service area can be set by the operator's investment plan instead of the existing method of selecting the area where the mobile phone service demand is low.

1 is a configuration diagram of a mobile communication system to which the method for setting an intergenerational service area according to the present invention can be applied;

2 is a flowchart illustrating a network access procedure of a dual band dual mode (DBDM) terminal in a mobile communication system to which a method for setting an intergenerational service area according to the present invention is applied.

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

110: CDMA base station controller 115: CDMA base station

120: WCDMA base station controller 125: WCDMA base station

Claims (2)

In the method of setting the intergenerational service area in a mobile communication system adopting a DBDM terminal in which a WCDMA overlay zone and a CDMA exclusive service zone coexist, and support both a WCDMA mobile telephone service function and a CDMA mobile telephone service function, Generating a WCDMA pseudo frequency including a pseudo code in an overhead channel while transmitting a CDMA frequency in a CDMA base station covering the CDMA single service area, and transmitting the WCDMA pseudo frequency to a boundary area of the CDMA single service area with the WCDMA overlay area; Wow, Transmitting, at a WCDMA base station, a WCDMA frequency with coverage of the WCDMA overlay service area; The DBDM terminal located in the boundary area between the CDMA exclusive service area and the WCDMA overlay service area identifies the boundary area as the CDMA exclusive service area based on a pseudo code included in the overhead channel of the WCDMA pseudo-frequency. Steps to connect to the network Generation service area setting method in a mobile communication system comprising a. The method of claim 1, When the plurality of frequencies are operated in the WCDMA overlay region, the CDMA base station generates the same number of the WCDMA pseudo frequencies in a hopping manner, and then adjusts and transmits the coverage for each frequency. An intergenerational service area setting method in a mobile communication system characterized by the above-mentioned.