KR100550183B1 - Wireless Network Design and Optimization Method for Frequency Communication Using Automatic Location Tracking Service - Google Patents

Abstract

The present invention utilizes AVL service data when performing TRS service and uses the location data transmitted from the mobile station and the radio transmission loss between the mobile station and the base station as a database to use as analysis data when designing the wireless network. The present invention relates to a TRS wireless network design and optimization method using an AVL service to improve call quality by controlling the control.

The present invention provides a first step of transmitting a transmission output power level of a mobile station terminal for power control and position data of a mobile station to an base station using an AVL system, and transmitting the position data and reception level of each mobile station from a base station to a control station. In the second step, the control station grasps the traffic and coverage of the mobile station, calculates the propagation loss between the mobile station and the base station according to the location of the mobile station, and converts the propagation environment characteristics of the base station into the radio network tool by converting the data into a database. The third step is to use.

Description

Design and Optimization of Wireless Network for Frequency Communication Using Automatic Location Tracking Service

The present invention relates to a digital radio communication system such as TRS (Trunked Radio System) and CDMA, PCS capable of Automatic Vehicle Location (AVL) service, and in particular, performs TRS business (cell planning: cell planning). Location data transmitted from mobile station and wireless transmission loss between mobile station and base station by using AVL service data at the time and use it as analysis data when designing wireless network and adjust the coverage according to traffic distribution of subscriber during optimization The present invention relates to a wireless network design and optimization method for TRS using AVL service.

In general, the tool used in the design of the wireless network is filled with terrain data and radio wave environment data of each region (high density downtown, downtown, and suburban areas), which is used for radio wave analysis, and calculates the coverage of each base station. do.

However, due to domestic conditions, building data (building height, area, etc.) are insufficient, it is difficult to calculate accurate coverage only with such data.

To compensate for this, the propagation loss caused by buildings is calculated through the drive test using a vehicle.

However, this method requires a lot of manpower and equipment, and takes a long time, making economic network design difficult.

In addition, if the location of the base station is selected according to the design of the wireless network, base station equipment is installed, and after installation, the call quality in the service area is improved through optimization work.

This optimization is done by analyzing the data obtained from the drive test and the reception level and FER measurements.

However, this task is difficult to measure the entire service area, and if there is a change in traffic distribution due to the increase of subscribers, it may be different from the subscriber traffic distribution predicted at the design stage of the wireless network.

The present invention has been made to solve such a conventional problem, and an object of the present invention is to use AVL service to efficiently design a wireless network and to improve the call quality by optimizing subscribers to improve the call quality. To provide a TRS wireless network design and optimization method using.

In order to achieve the above object, the present invention utilizes the AVL system as a database of the location data transmitted from the mobile station and the transmission loss between the mobile station and the base station to be used as analysis data in the design of the wireless network and the traffic distribution of the subscriber during the optimization operation. It is characterized by using a feedback method that adjusts the coverage according to the control method and adjusts the coverage when the traffic changes.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a diagram showing the overall configuration of the present invention, in which each base station 1-3 is connected to the control station 4 by an E1 line to transmit each signal, and FIG. 5 shows a mobile station communicating with the base station. It is shown.

Referring to the operation of the present invention configured as described above is as follows.

First, AVL is an efficient vehicle that locates the current position of the mobile station 5 vehicle using GPS or its own sensor and transmits location data and related information through a wireless network to perform terminal location reporting or monitoring. It refers to a system for the purpose of management, control, and control.

In the case of using such a system, as shown in FIG. 1, if the transmission output power level of the mobile station 5 terminal for power control and the position data of the mobile station 5 vehicle is transmitted to, for example, the base station 1 of cell 1 In the reception section of the base station 1, the AGC value is changed according to each reception level. Through this data, a path loss value on the radio section according to the position of the mobile station 5 can be obtained.

For example, if the terminal output power is 34dBm, the antenna gain is 3dBd, the base station reception antenna gain is 9dBd, and the reception level is -88dBm, the loss value in the radio section is calculated as follows. (However, device and cable loss in terminal and base station is 0dB.)

Propagation Loss = (34 + 9) + (9 + 88) = 140 dB

That is, the loss in the wireless section is 140dB, and the loss value is calculated according to the position of the terminal in this way, so that the database shown in Table 1 can be constructed.

TABLE 1

Base station number      Location data    Propagation Loss (dB)       One     36-45-21N 126-39-17E        140       2     37-18-46N 127-53-09E        125       ：         ：         ：

By using the database built as described above, it is possible to know the characteristics of the propagation environment (high density downtown, downtown, downtown area, etc.) of each region, for example, as shown in [Table 2].

TABLE 2

(Seoul area)

 division   Radio environment  Attenuation slope (dB / decade)   One   High density city center         43.1   2     Downtown         39.4   3   City center         38.5   4    Rural area         38.2

In the existing wireless network design tool, a propagation model has been developed based on the radio wave environment measured in the United States or Japan, and when used in the domestic radio environment, the error between the measured value and the measured value is large. In this case, more accurate wireless network design can be achieved and drive test work can be minimized.

In general, when the location of the base station 1-3 is selected according to the wireless network design, the base station equipment is installed, and after installation, optimization work is required to increase the call quality in the service area.

This optimization can be performed by using the position data of the vehicle of each mobile station 5 and the reception level information of the signal transmitted from the mobile station 5.

That is, as shown in FIG. 2, when the positions of the mobile stations 5 vehicles distributed on the highway and the national road are transmitted to the base station 1, the base station 1 calculates the position data and the reception level to control the station ( 4) to send.

Therefore, the control station 4 can grasp the traffic distribution and coverage of the vehicle on the basis of the value sent from the base station 1 and can adjust the base station output power.

That is, in the control station 4, when there is a change in the traffic distribution during the operation of the base station 1, after adjusting the coverage by adjusting the base station output power, the optimum coverage can be obtained based on the database.

The control station 4 calculates the propagation loss of the radio section between the mobile station 5 and the base station 1 by using the reception level.

In addition, it is possible to utilize the network design data after performing the propagation environment database on the basis of the calculated propagation loss.

The coverage of each of the base stations 1 to 3 obtained through the initial wireless network design is different from the actual service after installation of the equipment, and the flexible coverage is required to maintain the call quality because the traffic distribution changes due to the increase in subscribers. do.

The base stations 1 to 3 and the control station 4 are connected by a T1 / E1 line to monitor base station conditions through the base station controller in the control station 4 and to adjust system parameters such as base station output power.

Therefore, the present invention enables such a function, so that the mobile station 5 location data and the reception level data are databased in the computer in the control station 4, and as shown in FIG. In each case, it is possible to obtain a feedback algorithm that adjusts base station output power to re-control coverage and then obtains optimal coverage based on the database.

In FIG. 3, a, b, and c are mobile station traffic distributions, a represents upper, b middle, and c lower, X represents coverage before adjusting base station output power, and Y represents changed coverage after base station output power adjustment.

As described above, the present invention has an effect of more efficiently designing and optimizing a wireless network by using a AVL system as a database of location data of a mobile station and transmission loss between a mobile station and a base station.

1 is an overall structural diagram of the present invention

2 is a flow chart for the optimization of the present invention.

3 is an example of adjusting the coverage of each base station by grasping the traffic distribution of the mobile station on the road by the screen output on the control station monitor;

<Explanation of symbols for main parts of drawing>

1-3: Base station 4: Control station

5: Dongguk

Claims (2)

A first step of transmitting a transmission output power level of the mobile station terminal for power control and position data of the mobile station to the base station using the AVL system, A second step of transmitting, by a base station, location data and reception level of each mobile station to a control station; A third station that calculates propagation loss between the mobile station and the base station according to the position of the mobile station by grasping the traffic and coverage of the mobile station by the control station, and uses the in-coverage propagation environment characteristics of the base station in the wireless network tool by making a database of the radio environment; Wireless network design and optimization method for frequency common communication using automatic location tracking service characterized in that consisting of steps. The control station of claim 1, wherein If there is a change in the distribution of traffic during the operation of the base station, designing and optimizing the wireless network for the frequency common communication using the automatic location tracking service characterized by adjusting the base station output power to readjust the coverage and then obtaining the optimum coverage based on the database. .