KR100912340B1 - Method for calculating uplink multiservice channel capacity in wireless communication network - Google Patents

Abstract

1. TECHNICAL FIELD OF THE INVENTION

The present invention relates to a method for calculating uplink multiservice channel capacity in a wireless communication network.

2. The technical problem to be solved by the invention

The present invention supports multiple data rates so as to know information on the maximum channel capacity that can be accommodated for each service and operation environment (indoor, walking, vehicle), and uplink channel capacity of a CDMA method in consideration of various variable values. It is intended to provide a method for calculating uplink multiservice channel capacity.

3. Summary of Solution to Invention

According to an aspect of the present invention, there is provided a method for calculating uplink multiservice channel capacity, comprising: a first step of defining a limit of an amount of interference required by each service when supporting a multi-rate service at a different speed from voice; And a second step of calculating channel capacity for each transmission service based on the excess probability allowed by the system according to the total amount of limit interference for each service defined above.

4. Important uses of the invention

The present invention is used in a wireless communication network.

Multiple transport channel, uplink, multiple service, channel capacity

Description

Uplink capacity evaluation method for multi-rate services for wireless communication network             

1 is an exemplary configuration diagram of a broadband CDMA mobile communication network multiple service system to which the present invention is applied.

2 is a flowchart illustrating a method for calculating uplink multiservice channel capacity according to the present invention.

3 is an exemplary diagram showing the main parameters of the WCDMA and cdma2000 (3x) system for calculating the multi-service channel capacity according to the present invention.

4 is an exemplary view showing a variable value in each uplink channel environment for calculating a multi-service channel capacity according to the present invention.

5 is an exemplary diagram illustrating calculation of multiservice channel capacity of a WCDMA uplink in an indoor environment to which a multiservice channel capacity calculation scheme according to the present invention is applied.

6 is an exemplary diagram illustrating calculation of multi-service channel capacity of a cdma2000 (3x) uplink in an indoor environment to which the multi-service channel capacity calculation scheme according to the present invention is applied.

7 illustrates an example of calculating multi-channel channel capacity of WCDMA uplink in a pedestrian environment to which the multi-service channel capacity calculating scheme according to the present invention is applied.                 

FIG. 8 is an exemplary diagram of calculating a cdma2000 (3x) uplink multiservice channel capacity in a mobile vehicle environment to which a multiservice channel capacity calculation scheme according to the present invention is applied. FIG.

The present invention relates to a method for calculating uplink multiservice channel capacity in a wireless communication network, and in particular, simultaneous transmission of multiple services required for calculating channel capacity of an actual system (that is, simultaneous support of voice and data services of different rates at a base station). for. It supports multiple data rates so as to know information about the maximum channel capacity that can be accommodated for each service and operation environment (indoor, walking, vehicle), and to calculate uplink channel capacity of CDMA method considering various variable values. The present invention relates to a method for calculating uplink multiservice channel capacity.

The radio access standard (eg, WCDMA physical channel standard, cdma2000 physical channel standard of IMT-2000) adopted in the wireless communication system is the most important factor in determining system performance and capacity. Therefore, evaluating the performance and capacity of the wireless access standard through the objective evaluation model and simulation is essential not only for the design stage of the wireless access standard, but also for verifying the adoption of new technology and securing the optimal operation data of the system. Therefore, various numerical models of capacity analysis that can be applied to wideband CDMA method have been presented, and techniques for analyzing capacity in specific environments or in terms of optimization of parameters have been presented.

However, most of them focus on specific techniques or methods, and because the experimental environment is different from each other, it is difficult to compare them as capacity data. In addition, it does not reflect the multi-service or multi-rate support environment, which is the service operation environment of IMT-2000.

Therefore, the current generation of CDMA mobile communication channel capacity calculation technology overcomes the problems of the channel capacity calculation method that focuses on a specific technology or technique, and the conventional method of calculating capacity at one data rate, and the third generation mobile communication. There is a need for a scheme capable of supporting multiple data rates as required by the system and calculating uplink channel capacity of a CDMA scheme considering various variable values.

The present invention has been proposed to meet the above requirements, and supports multiple data rates so that information on the maximum channel capacity that can be accommodated for each service and for each operating environment (indoor, walking, vehicle) is known. It is an object of the present invention to provide a method for calculating uplink multiservice channel capacity for calculating uplink channel capacity of a CDMA method in consideration of various variable values.

According to an aspect of the present invention, there is provided a method for calculating an uplink multiservice channel capacity, comprising: a first step of defining a limit of an amount of interference required by each service when supporting a multi-rate service at a different speed from voice; And a second step of calculating channel capacity for each transmission service based on the excess probability allowed by the system according to the total amount of limit interference for each service defined above.

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The above objects, features and advantages will become more apparent from the following detailed description taken in conjunction with the accompanying drawings. Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is an exemplary configuration diagram of a broadband CDMA mobile communication network multi-service system to which the present invention is applied, and shows a multi-service base station of a third generation broadband CDMA mobile communication network providing multi-rate service.

As shown in FIG. 1, the uplink multi-rate capacity analysis assumes a base station that divides and operates a cell into sectors using a directional antenna, and ignores interference generated by users attempting to access. Consider only the interference caused by the users being connected. Assuming complete power control, the signal power received by the base station from each user using the same data rate service is the same.

2 is a flowchart illustrating an uplink multi-service channel capacity calculation method according to the present invention.

The base station from, for performing the uplink multi-service channel capacity calculation method according to the present invention, when a service that uses the transmission rate R _i are referred to as service i, one user uses the services i, as shown in Figure 2 If the received signal power is S _i , and the number of users of this service is represented by M _i , the power density S _{o, t} of the total power received from all users in the cell by the base station when no other cell is considered is given by It can be expressed as [Equation 1] of.

Here, B _w is the channel bandwidth (chip rate), N _o is the noise power density (single side PSD), N _r is the number of service rates supported by the system. In this case, since the power acting as an interference on the signal received from a user of the service i is the total received power minus the power of the magnetic signal, if the power density is I _{t, i} it is represented by [Equation 2] Same as

Here, the energy-per-bit of the signal transmission rate R _i as E _{b, i,} E _{b, i} is to of having a relationship of Equation 3, the reception of service i user E _{b, i} / I _{t, i} Is the same as Equation 4 below (201).

를 추가하면 하기의 [수학식 7]과 같다(202). 상기 [수학식 7]에서 일반적인

의 범위는 0.7에서 0.85이다.
In addition, the ratio between the interference power received from the users of the other cell and the current cellf , Considering interference from users in other cellsE                          _{b, i}                         / I                          _{t, i}  Equation 6 is given by Equation 6 below.                         

 Adding the same as in Equation 7 below (202). General in Equation 7 above

 Ranges from 0.7 to 0.85.
                    

Here, the ratio between the power received from the service 1 user and the power received from the service i user is defined as r _{s, i} as shown in Equation 8 below, and the number of sectors n in the cell is shown in Equation 7 above. Considering _s and the directional antenna gain G _a , E _{b, i} / I _{t, i} can be expressed as Equation 9 below (203, 204).

Therefore, if E _{b, i} / I _{t, i} necessary to satisfy the bit error rate required by a signal having a bit rate R _i is (E _b / I _t ) _{req, i} , E _{b, i} / I _{t, i} Since (E _b / I _t ) must be greater than _{req, i} , Equation 10 below must be satisfied for all i (205). [Equation 11] and [Equation 12] are derived from this.

Here, G _{p, i} is the spreading gain (= B _w / R _i ) of the i- th bit rate service. When the left side of Equation 12 is M _eq , Equation 2 is the same as Equation 14 below.

Equation 13 below indicates that the interference amount when the users of the service j have M _j persons is the same as the interference amount when only the users of the service 1 have M _eq without users of other services. That is, M _eq may be regarded as a value obtained by converting the total number of users into the number of users of service 1.

Then, the left-hand side value of the formula 12 in the above there is a user under consideration Is the use of a certain service, that is subject to R _i users to send, when the group represented by the values in F (i), the According to Equation 12, the following conditions must be met.

Each of the F (i) is will receive an influence on the r _{s, i} gajineunga a certain value, r _{s, i} is a value determined in the system design. From this _, r _{s, i,} which causes the maximum number of concurrently available users, is equal to F (1) = F (2) = F (3) =. We can conclude that r is equal to r _{s, i} . Thus, to be a multi-rate capacity that can accommodate a maximum of each r _s, the relationship of equation 16] for the _i between the need to establish and, r _s, of the following it can be expressed as ₁ [Equation 17] and Same (206).

는 얼랑을 단위로 하는 서비스 i 의 평균 제공 부하(offered load)가 된다.
From the above, a combination ( M ₁ , M ₂ , M ₃ ,... ) Of the number of users for each bit rate service that can be simultaneously accommodated in one cell can be derived. To calculate Erlang capacity per sector from this, it is assumed that the number of users transmitting in a cell can be modeled as a Poisson distribution. At this time, R _i in one cell The probability that k users will be transmitted at the bit rate, Pr [ k ] is given by Equation 18 below. here

Is the average offered load of service i in Erlang.

는 서비스 i 사용자의 평균 도착율(arrival rate),

는 서비스 i 사용자의 평균 서비스율(service rate),

는 활성요소(activity factor)이다. 각 전송률 서비스가 요구하는 BER을 만족시키지 못할 확률, 즉 시스템이 허용할 수 있는 최대 간섭량을 초과하여 서비스가 차단될 학률(outage probability), P _out 은 식 상기의 [수학식 12]로부터 M _max 를 하기의 [수학식 19]로 정의할 때, 하기의 [수학식 20]에서와 같이 M _eq 가 M _max 보다 커질 확률과 같다(207).
here,

Is the average arrival rate of service i users,

Is the average service rate for service i users,

Is the activity factor. The probability that each rate service does not meet the required BER, that is, the probability that the service will be blocked because it exceeds the maximum amount of interference that the system can tolerate, P _out is given by M _max from Equation 12 above. When defined by Equation 19 below, M _eq is equal to the probability that M _eq becomes greater than M _max as shown in Equation 20 below (207).

At this time, the relationship M ₁ , M ₂ ,... , M _N are independent of each other, so the relationship of Equation 21 below is established, and P _out by Equation 18, Equation 20, and Equation 21 results in Equation 22 below. It can be represented as.

의 조합으로 표현된다. 이 식으로부터 동시에 다중 전송률을 지원하며 운용환경 등, 다양한 변수 값이 고려된 CDMA 방식의 상향링크 채널용량을 산출할 수 있다(208).Per cell channel capacity, service-specific values in the uplink are specified in the P _out P _out, the service providing area, the average load can be maintained to less than _req

Is represented by a combination of From this equation, it is possible to calculate the uplink channel capacity of the CDMA scheme that supports multiple data rates simultaneously and takes into account various variable values such as an operation environment (208).

3 to 8, which will be described later, show a numerical analysis result of applying a channel capacity calculation model to multiple services and various environments of a mobile communication uplink according to the present invention.

3 is an exemplary diagram showing the main variables of the WCDMA and cdma2000 (3x) system for calculating the multi-service channel capacity according to the present invention, the WCDMA and cdma2000 (3x) of the representative standard of the next generation mobile communication system (IMT-2000) Physical channel main variables are shown.

값과 비례상수

값에 따라 결정된다.4 is an exemplary diagram showing variable values in each uplink channel environment for calculating a multi-service channel capacity according to the present invention, and each uplink channel environment (vehicular, pedestrian, indoor) of the next generation mobile communication system (IMT-2000). ) Shows the required variable values. The variable f is the soft handoff method and standard deviation of path loss.

Value and proportional constant

It depends on the value.

5 to 8 are examples of calculating channel capacity per cell in the WCDMA and cdma2000 methods by applying the variable values of FIGS. 3 and 4 according to a channel capacity calculation model in a multi-service and various environments of a mobile communication uplink according to the present invention. Indicates.

Here, each graph shows the capacity of three services for each system and each environment. Each axis represents capacity by service rate, and the repair on each axis at any point on the graph is the capacity for that service when three services are mixed.

The method of the present invention as described above may be implemented as a program and stored in a computer-readable recording medium (CD-ROM, RAM, ROM, floppy disk, hard disk, magneto-optical disk, etc.).

The present invention described above is not limited to the above-described embodiments and the accompanying drawings, and various substitutions, modifications, and changes can be made without departing from the technical spirit of the present invention. It will be apparent to those of ordinary skill in Esau.

As described above, the present invention can not only estimate the capacity per cell in various service rates and channel environments such as voice and data in a CDMA mobile communication network, but also know the simultaneous capacity of various services. In addition, it has the effect of increasing function and capacity through analysis of wireless access standard channel capacity and optimal operation of base station.

Claims (4)

In the uplink multi-service channel capacity calculation method, A first step of defining a limit on the amount of interference required by each service in supporting voice and multi-rate service at different rates; And A second step of calculating channel capacity for each transmission service based on the excess probability allowed by the system according to the total amount of the limit interference amount for each service defined above Uplink multi-service channel capacity calculation method in a wireless communication network comprising a. The method of claim 1, The first step is, According to the required minimum value (E _b / I _t ) _{req, i of} E _b / I _{t, i that} the user who transmits the predetermined i- th service bit rate, R _i , receives in each operating environment, each transmit bit rate user A method for calculating uplink multiservice channel capacity in a wireless communication network, characterized by defining a number M _j . The method according to claim 1 or 2, The second step, In order to calculate the maximum channel capacity per cell for each transmission bit rate and operation environment according to the total amount of the limit interference amount for each service, the channel capacity per cell for each service in the uplink is blocked ( P _out ). Average serving load per service that can keep below the specified value ( P _{out, req} )

In the wireless communication network, which supports multiple data rates simultaneously from the above equation and calculates uplink channel capacity of the code division multiple access (CDMA) method in consideration of operating environment and various variable values. A method of calculating uplink multiservice channel capacity. delete

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