Calculation of the required number of channels

This trail is part of the zone network, so the calculation takes into account the number of regional and district centers of population. Population in any regional center and the region as a whole can be determined based on census statistics. According to these data, the population of the city of KOCshetau for 2007-2008 amounted to 132.4 thousand people, and in Stepnogorsk -. 46.7 thousand people.. Population growth, taking into account is determined by the formula:

(1.1)

where H0 - population during the census thousand;. P - the average annual population growth in the area (taken as equal to 2-3%); T - period, defined as the difference between the designated year prospective design and the year of the census.

Year prospective design was adopted for 5-10 years ahead. This year the project planning stage to take 10 years to come. In accordance with this parameter T is determined by the formula:

T = 10 for + (Tm-T0), (1.2)

where Tm - year drafting; T0 - the year to which the data H0;

The average annual population increase in Akmola region accept equal to 3% (according to the statistics department). Using formula (1.2) define the parameter T:

T = 10 + (2016-2009) = 7, s

The population in the city of Stepnogorsk, according to (1.1) will be:

, thous. people

The population in the city of KOCshetau will be:

, thous. people

Considering that the telephone lines interurban and international communication are prevail, you must first determine the number of voice channels between specified localities. To do this, use the following formula:

N_TF=L×K_T×y× (1.3)

where: L and ß - constant coefficients corresponding to the predetermined fixed availability losses, loss usually assumed equal to 5%, while L = 1,3, and b = 5,6; K_T - gravitation factor; y - specific load, that is, the average load of the one person, y = 0,08 Earl; m_a, m_b- the number of subscribers served by AMTS terminals, respectively, in points A and B.

The relationship between the selected terminal and intermediate points is determined on the basis of statistical data from enterprises due for the preceding design years. In practice, this relationship is expressed in terms of gravitation coefficient K_T, which, studies show, it varies widely, from 0.1 to 12%. The project gravitation coefficient K_T is assumed equal to 10%, ie K_T = 0,1.

In the future, the number of subscribers served by AMTS terminal, determined according to the population living in the service area. Taking the average coefficient of equipment of public telephones in KOCshetau equal to 0.8, in Stepnogorsk - 0.2 subscribers in AMTS zone can be determined by the formulas:

m_a¹=0,8×H_Т¹, (1.4)

m_b²=0,2×H_Т², (1.5)

Inserting data into the formula (1.4) and (1.5) define the number of subscribers served endpoints AMTS:

m_a¹= 0,8×188,77 = 151,016, thousand. people

m_в²= 0,2×66,583 = 13,3166, thousand. people

Using formula (1.3) determine the number of voice channels:

n_ТФ=1,3×0,1×0,08× + 5,6 = 133, channels

In the cable transmission line isolated channels and other types of communications: data wire, radio, etc., also take into account the transit channels. In this case, the number of transit links will not be taken into account, they will be taken into account when choosing a transmission system.

Since the number of channels for communication for various purposes can be expressed by the number of voice channels, i.e. VF channels, it is advisable to the total number of channels between the points expressed by the PM channels.

Generally, the total number of channels is calculated according to the simplified formula:

n = 2×n_Т_F, (1.6)

n = 133×2 = 266, channel

This calculation was made without taking into account the number of backhaul. So if you take into account the transit flows as well as prospects for further development of the network and the possibility of damage which may be necessary to bypass the organization through this highway, then the projected line required transmission speed is 155 Mbit / s (1890 channels).

As the transmission system I suggest using SDH equipment operating over a fiber-optic cable.

The planned establishment of a communication scheme is shown in Figure 3 [PA].

The diagram also shows the required number of PCM streams to be allocated in the corresponding paragraphs.

The technical part