CN1929635A - Method and system for base station transmission power setting in wireless honeycomb network - Google Patents

Abstract

The invention relates to the field of wireless communication, and discloses a method and system for setting the transmission power of a base station in a wireless cellular network, so that the transmission power of a newly-built base station can be set without resorting to drive test and network planning, and the set transmission power No interference to existing base stations. In the present invention, the network includes a network database for storing existing base station information, the coverage of the existing base station can be obtained through the network database, the coverage of the new base station is calculated according to the coverage of the existing base station, and further according to the coverage of the new base station The coverage area of the newly built base station is calculated by the path loss calculation formula, and then according to the path loss of the newly built base station, the transmit power of the newly built base station is finally determined through the relationship between the base station path loss and the transmit power. When the calculated coverage is greater than the expected coverage of the newly built base station, the expected coverage of the newly built base station shall prevail.

Description

Method and system for setting transmit power of base station in wireless cellular network

technical field

The invention relates to the field of wireless communication, in particular to the base station setting technology in the wireless cellular network.

Background technique

Cellular technology is a wireless communication technology. This technology divides a geographic area into several small cells, called "cells" (ie cells), hence the name of the cellular technology.

Dividing a large geographical area into multiple "cells" is to make full use of the limited wireless transmission frequencies. Each set of connections requires a dedicated frequency. In order to allow more conversations to take place simultaneously, cellular systems assign a certain amount of frequency to each "cell" (ie, each small area). Non-adjacent cells can use the same frequency, so that limited radio resources can be fully utilized. Currently common cellular systems include Global System for Mobile communication (GSM for short) and Code Division Multiple Access (CDMA for short).

According to the functions, cellular mobile communication systems can be roughly divided into three categories, namely: macro cells, micro cells and smart cells. Next, briefly describe macrocell and microcell.

Macrocellular technology is first described. In the cellular mobile communication system, in the early stage of network operation, the main goal of the operator is to build a large macro cell to obtain as large a coverage as possible. The coverage radius of the macro cell is mostly 1km to 25km, and the base station antennas should be as large as possible. Do it high.

In an actual macro cell, there are usually two special micro areas. One is the "blind spot", which is a shadow area caused by obstacles encountered in the propagation of radio waves, and the communication quality in this area is seriously poor; the other is "hot spot", which is a busy area formed by the uneven distribution of space service load. It supports most of the services in macro cells. The solutions to the above two "points" problems often rely on methods such as setting up repeaters and splitting cells. In addition to economic reasons, in principle, these two methods cannot be used without restriction, because the communication quality will decrease if the system coverage is expanded; the capacity will often be sacrificed if the communication quality is improved. In recent years, with the increase of users, the macro cells are divided into cells and become smaller and smaller. When the cell is small to a certain extent, the cost of site construction will increase sharply, and the reduction of the cell radius will also bring serious interference. On the other hand, blind spots still exist, and high traffic in hot spots cannot be well absorbed.

Compared with macro-cell technology, micro-cell technology has small coverage, low transmission power, and convenient and flexible installation. The coverage radius of this cell is 30m to 300m, and the base station antenna is lower than the height of the roof. The propagation is mainly along the line of sight of the street. Signal leakage on the roof is small. Microcells can be used as a supplement and extension of macrocells. The application of microcells mainly has two aspects: one is to improve the coverage rate and apply to some blind spots that are difficult to cover by macrocells, such as subways and basements; the other is to increase capacity, mainly Applied in areas with high traffic volume, such as bustling commercial streets, shopping centers, stadiums, etc. When used as an application to increase network capacity, microcells generally form a multi-layer network with macrocells. The macro cell covers a large area, as the bottom layer of the multi-layer network, and the micro cell covers a small area continuously and superimposes on the macro cell to form the upper layer of the multi-layer network. The micro cell and the macro cell are different cells in terms of system configuration. There is an independent broadcast channel.

In the prior art, the wireless cellular network is planned and constructed by the operator in a unified manner. Operators determine the division of cells in the network based on information such as coverage and capacity requirements, and determine the coverage of each base station in the network, the location of the base station site, and the transmit power of the base station. Network planning requires professionals to adjust base station parameters according to the unified planning of the entire network, along with drive test information during network optimization. As a result, the cost and technical requirements of network construction are very high. On the basis of the macro cellular network established by the operator, it can decide whether to add a micro cellular network and build a corresponding base station according to the wireless signal coverage of the location. Since the microcellular network is not uniformly established by the operator, complex drive tests or network planning cannot be performed on it. Without drive test and network planning, the coverage area of the base station and the transmission power of the base station cannot be well determined. The transmission power of the new base station is likely to interfere with the original base station.

Contents of the invention

In view of this, the main purpose of the present invention is to provide a method and system for setting the transmit power of a base station in a wireless cellular network, so that the transmit power of a newly built base station can also be set without resorting to drive testing and network planning, and the set The transmit power will not interfere with existing base stations.

In order to achieve the above object, the present invention provides a method for setting transmit power of a base station in a wireless cellular network, comprising the following steps:

Obtaining the coverage of the existing base station from the network database storing the information of the existing base station, and calculating the coverage of the new base station according to the coverage of the existing base station;

calculating the path loss of the newly-built base station according to the calculated coverage of the newly-built base station;

Calculate and set the transmit power of the newly-built base station according to the calculated path loss of the newly-built base station.

Wherein, when the calculated coverage is greater than the expected coverage of the newly-built base station, the coverage of the newly-built base station is the expected coverage;

Calculate the path loss of the newly-built base station according to the expected coverage.

In addition, in the method, the path loss of the newly-built base station is calculated by the path loss formula PL=F(f, d, ht, hr, terrain parameters), the path loss formula is based on the operating frequency f of the base station, the distance between the base station and the terminal d , base station antenna height ht, terminal antenna height hr, and terrain parameters are used as parameters to calculate the path loss of the base station; where, the distance between the base station and the terminal is determined by the coverage of the base station.

In addition, in the method, the operating frequency of the base station, the height of the base station antenna, the height of the terminal antenna, and the terrain parameters are input by the personnel setting up the base station or obtained from the network database.

In addition, in the method, the transmit power of the newly-built base station is calculated through the relationship between base station path loss and transmit power, which is:

PL=Ptx+Gant_t-Prx+Grant_r;

where PL is the path loss of the base station;

Ptx is the transmit power of the base station;

Gant_t is the antenna gain of the base station;

Gant_r is the antenna gain of the terminal;

Prx is the receiving sensitivity of the terminal;

Gant_t, Gant_r, and Prx are input by base station setup personnel or obtained from the network database.

In addition, in the method, if the calculated transmit power of the base station is greater than the maximum transmit power of the newly-built base station, then the transmit power of the newly-built base station is the maximum transmit power.

In addition, in the method, if the calculated transmit power of the base station is greater than the maximum transmit power of the newly-built base station, the newly-built base station re-determines its coverage area according to the maximum transmit power.

In addition, in the method, the newly-built base station reports base station information including transmission power and coverage to a network database.

The present invention also provides a system for setting transmission power of a base station in a wireless cellular network, which includes a network database for storing information of existing base stations and a new base station, and also includes:

A device for obtaining the coverage of an existing base station from the network database, and calculating the coverage of the new base station according to the obtained coverage of the existing base station;

A device for calculating the path loss of the newly-built base station according to the calculated coverage of the newly-built base station;

A device for calculating and setting the transmit power of the newly-built base station according to the calculated path loss of the newly-built base station.

Wherein, it also includes a device for saving the parameter information of the newly-built base station in the network database.

Through comparison, it can be found that the main difference between the technical solution of the present invention and the prior art is that the network contains a network database for storing information of existing base stations, and the coverage of existing base stations can be obtained through the network database. Calculate the coverage of the new base station based on the coverage of the new base station, and further calculate the path loss of the new base station through the path loss calculation formula according to the coverage of the new base station, and then according to the path loss of the new base station, through the relationship between the base station path loss and the transmit power, The transmit power of the newly-built base station is finally determined. Therefore, there is no need for network planning or drive testing, and the transmit power of the newly-built base station can also be correctly set through the information stored in the network, and because the actual situation of the existing base station is combined in the process of determining the transmit power, there is no need for existing base stations. The base station is causing interference.

When the calculated coverage area is greater than the expected coverage area of the new base station, the coverage area of the new base station shall be based on the expected coverage area to avoid negative impact on the determination of the coverage area of the new base station when the existing base station distribution is unreasonable .

When the determined transmit power of the base station is greater than the maximum transmit power of the newly-built base station, the transmit power of the newly-built base station is based on the maximum transmit power. Make the transmission power set by the newly built base station not exceed the maximum transmission capability of the base station, so as to ensure the normal operation of the base station.

When the transmission power of the new base station is changed from the determined value to its maximum transmission power, the coverage area of the base station is re-determined according to the maximum power, so as to avoid the inconsistency between the coverage area determined by the new base station and the actual coverage area, and ensure the normal operation of the new base station.

After the transmission power setting is completed, the new base station will report the base station information including the transmission power and coverage to the network database for storage, so as to ensure that the information in the network database can be updated in time, so that the base station built later can also be accurate according to the information in the network database. Set its transmit power accordingly.

Description of drawings

Fig. 1 is a network diagram of a base station transmission power setting method and system in a wireless cellular network of the present invention;

2 is a flow chart of a method for setting transmit power of a base station in a wireless cellular network according to a first embodiment of the present invention;

Fig. 3 is a system structure diagram of setting transmit power of a base station in a wireless cellular network according to a second embodiment of the present invention.

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings.

The core of the present invention is that a network database for storing existing base station information is included in the network. As shown in FIG. Coverage, and further according to the coverage of the new base station, calculate the path loss of the new base station through the path loss calculation formula, and then use the relationship between the base station path loss and the transmission power to finally determine the transmission power of the new base station. Therefore, there is no need for network planning or drive testing, and the transmission power of the newly-built base station can also be correctly set through the information stored in the network.

The first embodiment of the present invention will be described below based on the principles of the present invention.

As shown in FIG. 2, in step 201, the newly-built base station acquires its related setting information. Including the antenna height of the base station, the antenna parameters of the base station (such as installation direction, directional gain, pattern, etc.), the operating frequency of the base station, the maximum transmission power capability of the base station, the geographical location information of the base station, the expected coverage of the base station, and the application of the base station Conditions: indoor or outdoor, terrain parameters of the base station (can be selected from several existing typical application environments). These information can be directly input by the base station setting personnel or automatically obtained by the base station.

Then enter step 202, the base station is connected with the network database storing the existing base station information, and obtains the information of the adjacent existing base station, including the operating frequency of the adjacent base station, the geographical location information of the adjacent base station, the coverage information of the adjacent base station (the information It can be stored according to two-dimensional or three-dimensional map information), and the application conditions near the base station: indoor/outdoor.

Then enter step 203, estimate the coverage of the new base station according to the acquired coverage of the neighboring base stations. For example, it can be set that the overlapping area between the coverage area of the newly-built base station and the coverage area of the surrounding adjacent base stations does not exceed 10%, and the coverage area of the newly-built base station is calculated according to the antenna parameters through a geometric calculation method.

Then enter step 204, judge whether the calculated coverage is greater than the expected coverage of the new base station, if greater, then enter step 205, replace the estimated coverage with the expected coverage, to avoid when the existing base station distribution is unreasonable, for If the determination of the coverage of the new base station has a negative impact, then go to step 206; if the calculated coverage is less than or equal to the expected coverage, go to step 206 directly.

In step 206, according to the coverage of the newly-built base station, the path loss of the newly-built base station is calculated by the path loss formula PL=F(f, d, ht, hr, terrain parameters). The path loss formula takes base station operating frequency f, distance d between base station and terminal, base station antenna height ht, terminal antenna height hr, and terrain parameters as parameters. In actual application, the path loss calculation formula can be embodied according to the prior art to realize the path loss calculation. Among them, the distance between the base station and the terminal is determined by the coverage of the newly built base station, the operating frequency of the base station, the height of the base station antenna, and the terrain parameters are obtained from the information input by the personnel who set up the base station, and the height of the terminal antenna can be obtained from the network database.

Then enter step 207, according to the path loss of the newly-built base station, the transmit power of the newly-built base station is calculated through the relational expression between base station path loss and transmit power. The relationship between the path loss of the base station and the transmit power is: PL=Ptx+Gant_t-Prx+Grant_r, where PL is the path loss of the base station; Ptx is the transmit power of the base station; Gant_t is the antenna gain of the base station; Gant_r is the antenna of the terminal Gain; Prx is the receiving sensitivity of the terminal. In practical applications, the base station path loss calculated in the previous step can be combined with the antenna gain of the base station and the terminal, and the receiving sensitivity of the terminal to derive the transmit power of the newly built base station. The antenna gain of the base station in the relational formula can be obtained according to the antenna parameters of the base station (including installation direction, directional gain, and pattern). The receiving sensitivity and antenna gain of the terminal are fixed values in the same system and can be obtained from the network database.

Then enter step 208, judge whether the calculated base station transmission power is greater than the maximum transmission power of the newly-built base station, if greater then enter step 209, carry out the setting of transmission power to this newly-built base station according to this maximum transmission power, guarantee the emission that the newly-built base station sets The power does not exceed the maximum transmission capability of the base station to ensure the normal operation of the base station, and then enter step 211; otherwise, enter step 210, and set the transmission power of the newly-built base station according to the calculated transmission power. It can be seen that without network planning or drive test, the transmission power of the newly built base station can also be correctly set through the information stored in the network, and because the actual situation of the existing base station is combined in the process of determining the transmission power, there is no need to Interference with existing base stations.

In step 211, according to the maximum transmission power of the newly-built base station, its actual coverage area is re-determined, to avoid the coverage area determined by the newly-built base station from being inconsistent with the actual coverage area, and to ensure the normal operation of the newly-built base station.

Then enter step 212, save the base station information including transmission power and coverage in the network database, ensure that the information in the network database can be updated in time, so that the base station built later can also accurately set its transmission power according to the information in the network database . If the transmit power of the newly-built base station is the calculated transmit power, save the transmit power and the previously calculated coverage in the network database; if the transmit power of the newly-built base station is the maximum transmit power, the maximum transmit power and the newly determined Save in the network database to ensure the accuracy of the information in the network database.

In this embodiment, the calculation of the coverage, the calculation of the path loss, and the calculation and setting of the transmission power can be carried out in the new base station or the network database. If it is carried out in the new base station, then in step 212 the base station needs to include the transmission The base station information including power and coverage is reported to the network database and stored by the network database. If implemented in the network database, it can be directly stored by it. In the entire transmission power setting process, except for manual input, other steps can be completed by the cooperation of the newly built base station and the network database, thereby simplifying the manual workload. In addition, many information that needs to be manually input can also be obtained automatically, such as the geographical location information can be obtained according to the supporting Global Position System (GPS), and the maximum transmission power information can be obtained from the settings of the base station manufacturer.

The base station transmission power setting system in the wireless cellular network of the second embodiment of the present invention is described below. As shown in FIG. 3 , the base station transmission power setting system in the wireless cellular network includes a network database for storing existing base station information, a new base station, and : a coverage calculation device for obtaining the coverage of existing base stations from the network database, and calculating the coverage of the new base station according to the obtained coverage of the existing base stations; used for calculating the new base station according to the calculated coverage A path loss calculation device for the path loss of the newly built base station; a transmit power setting device for calculating and setting the transmit power of the newly built base station according to the path loss of the newly built base station; and a reporting device for saving the parameter information of the newly built base station to the network database.

Specifically, in the base station transmission power setting system in the wireless cellular network, the coverage area calculation device obtains the coverage area of the existing base station from the network database, and calculates the coverage area of the new base station according to the obtained coverage area of the existing base station , and pass the estimated coverage to the path loss calculation device. The path loss calculation device further calculates the path loss of the newly-built base station according to the coverage area and through the path loss formula, and transmits the calculation result to the transmission power setting device. The transmission power setting device calculates the reasonable transmission power of the new base station through the relationship between the base station path loss and the transmission power based on the path loss calculated by the computing device, and sets the transmission power of the new base station according to the transmission power, so as to achieve No network planning or drive test is required, and the transmit power of the newly built base station can also be correctly set through the information stored in the network. And because the actual situation of the existing base station is combined in the process of determining the transmission power, no interference will be generated to the existing base station. After the transmission power setting device completes the power setting, it triggers the reporting storage module to save the parameter information of the newly-built base station including the transmission power and coverage to the network database, so as to ensure that the information in the network database can be updated in time, so that the base station built later can also It can accurately set its transmission power according to the information in the network database.

Among them, the path loss formula PL=F(f, d, ht, hr, terrain parameters) uses the base station operating frequency f, the distance between the base station and the terminal d, the base station antenna height ht, the terminal antenna height hr, and terrain parameters as parameters to calculate the base station path loss. The distance between the base station and the terminal is determined by the coverage of the base station. The operating frequency of the base station, the height of the base station antenna, the height of the terminal antenna, and terrain parameters are input by the base station setter or obtained from the network database.

The relationship between base station path loss and transmit power is: PL=Ptx+Gant_t-Prx+Gant_r. Among them, PL is the path loss of the base station, Ptx is the transmit power of the base station, Gant_t is the antenna gain of the base station, Gant_r is the antenna gain of the terminal, and Prx is the receiving sensitivity of the terminal. Among them, Gant_t, Gant_r and Prx are input by the base station setting personnel or obtained from the network database.

It is worth mentioning that the coverage calculation device, path loss calculation device, transmission power setting device, and reporting device mentioned in the second embodiment are logical concepts, which can be physically implemented in different devices or in the same device implemented in or directly in the base station. The above-mentioned devices can have various names, but as long as they have the above-mentioned functions and can realize the effects of the present invention, they belong to the protection scope of the present invention. It can be understood that the functions involved in the coverage calculation equipment, path loss calculation equipment, transmit power setting equipment, and reporting equipment are mainly to calculate coverage, calculate path loss, set transmit power, and report and store information. These functions are not difficult It is realized by known technologies, but the present prior art does not realize the purpose of the present invention through the creative combination of these functions.

Although the present invention has been illustrated and described with reference to certain preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the present invention. The spirit and scope of the invention.

Claims (10)

1. the method that base station transmitting power is provided with in the wireless cellular network is characterized in that, comprises following steps:

From the network data base of storing existing base station information, obtain the coverage of existing base station, calculate the coverage of newly-built base station according to the coverage of described existing base station;

According to the coverage of the described newly-built base station that calculates, calculate the path loss of described newly-built base station;

According to this newly-built base station path loss that calculates, calculate and be provided with the transmitting power of this newly-built base station.

2. the method that base station transmitting power is provided with in the wireless cellular network according to claim 1, it is characterized in that, during greater than the coverage of newly-built base station expects, the coverage of described newly-built base station is got the coverage of this expection in the coverage of described calculating;

Calculate the path loss of described newly-built base station according to the coverage of this expection.

3. the method that base station transmitting power is provided with in the wireless cellular network according to claim 1, it is characterized in that, by path loss formula PL=F (f, d, ht, hr, terrain parameter) calculate the path loss of described newly-built base station, this path loss formula is parameter with base station working frequency f, base station and terminal apart from d, base station antenna height ht, terminal antenna height hr and terrain parameter, the path loss of calculation base station; Wherein, base station and terminal distance is determined by the coverage of base station.

4. the method that base station transmitting power is provided with in the wireless cellular network according to claim 3, it is characterized in that described base station working frequency, base station antenna height, terminal antenna height and terrain parameter are provided with personnel's input by the base station or obtain from described network data base.

5. the method that base station transmitting power is provided with in the wireless cellular network according to claim 1 is characterized in that calculate the transmitting power of newly-built base station by the relational expression of base station path loss and transmitting power, this relational expression is:

PL＝Ptx+Gant_t-Prx+Grant_r；

Wherein, PL is the path loss of base station;

Ptx is the transmitting power of base station;

Gant_t is the antenna gain of base station;

Gant_r is the antenna gain of terminal;

Prx is the receiving sensitivity of terminal;

Gant_t, Gant_r, Prx are provided with personnel's input by the base station or obtain from described network data base.

6. the method that base station transmitting power is provided with in the wireless cellular network according to claim 1, it is characterized in that, if the base station transmitting power that calculates is greater than the maximum transmission power of described newly-built base station, then the transmitting power of described newly-built base station is this maximum transmission power.

7. the method that base station transmitting power is provided with in the wireless cellular network according to claim 6, it is characterized in that, if the base station transmitting power that calculates is greater than the maximum transmission power of described newly-built base station, then described newly-built base station redefines its coverage according to this maximum transmission power.

8. the method that is provided with according to base station transmitting power in each described wireless cellular network in the claim 1 to 7 is characterized in that described newly-built base station will comprise the base station information report network database of transmitting power and coverage.

9. the system that base station transmitting power is provided with in the wireless cellular network is characterized in that, comprises the network data base and the newly-built base station that are used to store existing base station information, also comprises:

Be used for obtaining the coverage of existing base station, and calculate the equipment of the coverage of this newly-built base station according to the coverage of the existing base station that is obtained from described network data base;

Be used for calculating the equipment of the path loss of this newly-built base station according to the coverage of this newly-built base station of calculating;

Be used for according to this newly-built base station path loss calculation that calculates and the equipment that the transmitting power of this newly-built base station is set.

10. the system that base station transmitting power is provided with in the wireless cellular network according to claim 9 is characterized in that, also comprises

The parameter information of described newly-built base station is saved in the equipment of described network data base.

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