KR100576001B1 - Method for calculating frequency reuse efficiency of mobile communication system - Google Patents

Abstract

According to an aspect of the present invention, there is provided a method for calculating frequency reuse efficiency in a mobile communication system that simultaneously services a mobile terminal and a fixed terminal, the method comprising: calculating a frequency reuse efficiency of each of the mobile terminal and the fixed terminal; And a third process of calculating the ratio and the reception intensity ratio, and a third process of calculating the frequency reuse efficiency in consideration of the channel ratio and the reception intensity ratio.

Frequency reuse efficiency.

Description

How to calculate frequency reuse efficiency in mobile communication system {METHOD FOR CALCULATING FREQUENCY REUSE EFFICIENCY OF MOBILE COMMUNICATION SYSTEM}             

1 is a flowchart illustrating a method of calculating frequency reuse efficiency in a mixed service of a mobile terminal and a fixed terminal according to an embodiment of the present invention in a mobile communication system.

The present invention relates to a method for calculating frequency reuse efficiency in a mobile communication system, and more particularly, to a method for calculating frequency reuse efficiency when simultaneously serving a mobile terminal and a fixed terminal.

In general, frequency reuse efficiency refers to the frequency of each cell area to make it smaller so that a larger number of cells control the same geographical area in order to increase the number of subscribers that can serve in a single wireless network. Maximizing reuse is a parameter that must be considered when deciding capacity and coverage when designing a wireless network in a CDMA system.

However, in the conventional mobile communication system, frequency reuse efficiency has been calculated for a service for a mobile subscriber. In case of targeting the fixed subscribers, the frequency reuse efficiency is calculated to serve only the fixed subscribers. That is, the conventional method of calculating the frequency reuse efficiency has been a method of calculating the frequency reuse efficiency for the service of only one part for the mobile subscriber or the fixed subscriber. Therefore, the conventional frequency reuse efficiency calculation scheme in a mobile communication system does not satisfy the requirements of the system for satisfying simultaneous services for mobile subscribers and fixed subscribers.

On the other hand, in countries where there is a lack of communication networks, such as Russia and China, there is a need for a system that can satisfy not only services for fixed subscribers but also services for some mobile subscribers. That is, a hybrid system capable of serving both fixed subscribers and mobile subscribers by applying a CDMA system similarly to a WLL network is required. Therefore, there is a need to analyze the efficiency of reverse link frequency reuse in a system serving both fixed and mobile subscribers simultaneously.

Accordingly, an object of the present invention is to provide a method for calculating the frequency reuse efficiency when simultaneously serving a mobile terminal and a fixed terminal in a mobile communication system.                         

In accordance with another aspect of the present invention, there is provided a method for calculating frequency reuse efficiency in a mobile communication system for simultaneously serving a mobile terminal and a fixed terminal, the method including calculating a frequency reuse efficiency of each of the mobile terminal and the fixed terminal; And a second process of calculating a channel ratio and a reception strength ratio of the mobile terminal and the fixed terminal, and a third process of calculating the frequency reuse efficiency in consideration of the channel ratio and the reception strength ratio.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. First of all, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are used as much as possible even if displayed on different drawings. In the following description of the present invention, detailed descriptions of related well-known functions or configurations are omitted when it is determined that the detailed description may unnecessarily obscure the subject matter of the present invention.

The frequency reuse efficiency of the reverse link of the mobile communication system depends on which antenna is used by the base station and the terminal. In addition, in the case of using a hybrid scheme, a mobile subscriber service uses a omnidirectional dipole antenna, but a mobile subscriber service uses a directional patch antenna in many cases. This makes a big difference between the frequency reuse efficiency value for mobile subscriber service and the frequency reuse efficiency value for fixed subscriber service. In addition, since the Eb / No value required for the mobile subscriber service and the Eb / No value required for the fixed subscriber service are different from each other, the strength of the received signal also varies according to the mobile subscriber service and the fixed subscriber service.

Therefore, in the case of simultaneously serving the mobile terminal and the fixed terminal, for each mobile terminal or the fixed terminal, the frequency reuse efficiency value for the service of only one portion, the channel ratio of the mobile terminal and the fixed terminal, and the ratio of the reception strength In consideration of this, the frequency reuse efficiency value should be calculated.

1 is a flowchart illustrating a method of calculating frequency reuse efficiency in a mixed service of a mobile terminal and a fixed terminal according to an embodiment of the present invention in a mobile communication system.

In step 110, first, each frequency reuse efficiency is obtained for the case of serving only a mobile terminal and for serving only a fixed terminal. The frequency reuse efficiency of the reverse link varies depending on the antenna used by the base station and the terminal. Hereinafter, the calculated frequency reuse efficiency of the mobile terminal is referred to as 'Fm', and the frequency reuse efficiency of the fixed terminal is referred to as 'Ff'.

In operation 120, the frequency reuse efficiency (F) for the mixed service is calculated in consideration of the channel ratio and the reception strength ratio of the mobile terminal and the fixed terminal. The frequency reuse efficiency calculation method for the mixed service is as follows.

That is, assuming the ratio of the occupied channel by the mobile terminal to the fixed terminal and the occupied channel by the fixed terminal in the sector as shown in Equation 1 below.

Y denotes a channel ratio of a mobile terminal and a fixed terminal in one sector, Nm denotes a channel capacity of a mobile terminal in a mixed service, and Nf denotes a channel capacity of a fixed terminal in a mixed service.

Assuming a ratio of the reception strength of the mobile terminal to the reception strength of the fixed terminal, Equation 2 is obtained.

K denotes a reception strength ratio of the fixed terminal and the mobile terminal, Pm denotes a reception strength of the mobile terminal, and Pf denotes a reception strength of the fixed terminal.

Here, K is determined by the reception tax period association required for the mobile terminal and the fixed terminal, and is expressed by Equation 3 below.

는 요구되는 이동 단말기의 Eb/No를 의미하며, 상기

는 요구되는 고정 단말기의 Eb/No를 의미한다. 그리고 상기

는 파일롯 신호의 이득을 의미하며, 상기

는 음성 액티비티(Activity)를 의미한다.remind

Means Eb / No of the required mobile terminal, and

Means Eb / No of the required fixed terminal. And said

Is the gain of the pilot signal, and

Means voice activity.

On the other hand, the total signal strength received by the base station receiver on the reverse link is composed of the sum of the signal generated by the mobile terminal, the signal generated by the fixed terminal, and the noise floor generated by the amplifier of the receiver itself.

The strength of the signal generated by the mobile terminal is expressed by Equation 4 below.

이동 단말기에 의해 발생하는 신호의 세기=

Signal strength generated by the mobile terminal

Nm means occupied channel by the mobile terminal in one sector, Pm means reception strength of the mobile terminal, Fm means frequency reuse efficiency of the mobile terminal, Es means Sectorization efficiency. .

And the intensity of the signal generated by the fixed terminal is as shown in Equation 5 below.

고정 단말기에 의해 발생하는 신호의 세기=

Signal strength generated by fixed terminals

The Nf means the occupied channel by the fixed terminal in one sector, the Pf means the reception strength of the fixed terminal, the Ff means the frequency reuse efficiency of the fixed terminal, the Es means the Sectorization efficiency. .

Therefore, when the thermal noise floor generated by the receiver itself amplifier is called 'Nth', the total signal received by the base station receiver of one cell is represented by Equation 6 below.

Meanwhile, the signal-to-noise ratio of one mobile terminal when the mobile terminal and the fixed terminal are mixed can be expressed by Equation 7 below.

은 요구되는 이동 단말기의 S/N비를 의미하며, 상기 F는 혼용 서비스시 주파수 재사용 효율을 의미한다.remind

Denotes the required S / N ratio of the mobile terminal, and F denotes the frequency reuse efficiency in the mixed service.

The signal-to-noise ratio of one fixed terminal when the mobile terminal and the fixed terminal are mixed can be expressed by Equation (8).

은 요구되는 고정 단말기의 S/N비를 의미하며, 상기 F는 혼용 서비스시 주파수 재사용 효율을 의미한다.remind

Denotes the S / N ratio of the required fixed terminal, and F denotes the frequency reuse efficiency in the mixed service.

In the above equations, the total signal received by the base station receiver of one cell may be represented by Equation 9 below.

Here, F means frequency reuse efficiency in a mixed service.

On the other hand, since the values of <Equation 6> and <Equation 9> are the same, it can be developed by the following equation (10).

In Equation 10, F is a frequency reuse efficiency value at the time of mixing the mobile terminal and the fixed terminal.

In Equation 11, Nm / Nf is Y, which is a channel ratio between a mobile terminal and a fixed terminal in one sector, and Pm / Pf is K, which is a reception intensity ratio between a fixed terminal and a mobile terminal. Therefore, Equation 11 may be represented by Equation 12 below.

Here, F denotes a frequency reuse efficiency value when the mobile terminal and the fixed terminal are mixed, Y denotes a channel ratio of the mobile terminal and the fixed terminal in one sector, and K denotes a channel ratio of the fixed terminal and the mobile terminal. Receive intensity ratio.

As described above with reference to FIG. 1, in the mobile communication system, when the mobile terminal and the fixed terminal simultaneously service the mobile terminal or the fixed terminal, each frequency reuse efficiency value for the service of only one portion and In addition, it can be seen that the frequency reuse efficiency value is calculated in consideration of the ratio of the channel ratio and the reception strength of the mobile terminal and the fixed terminal.

As described above, the present invention can calculate a frequency reuse efficiency value when a mobile terminal and a fixed terminal are used in a mobile communication system, and provide simultaneous services for the fixed terminal as well as the mobile terminal through reverse link frequency reuse analysis. There is an advantage that the frequency capacity and coverage can be effectively estimated when designing the wireless network of the system to meet.

Claims (1)

In the method of calculating the frequency reuse efficiency in a mobile communication system serving a mobile terminal and a fixed terminal at the same time, Calculating a frequency reuse efficiency of each of the mobile terminal and the fixed terminal; A second process of calculating a channel ratio and a reception strength ratio of the mobile terminal and the fixed terminal; And a third process of calculating a frequency reuse efficiency in consideration of the channel ratio and the reception strength ratio.

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