Боцман Я. В. Дочірнє підприємство “S & T Soft-Tronik” Україна, 03056, Київ, вул. Кудрявська, 11а Тел.: +38 (044) 238-6388; e-mail: yaroslav.botsman @ snt.ua

Botsman Y. V.

«S&T Soft-Tronik»,

11a, Kudryavskaya str.

Kyiv, Ukraine, 03056, tel.: +38 238-6388,

E-mail: yaroslav.botsman@snt. ua

The summary – A mathematical model of a quantitative rating of reliability of transfer of the information in Ethernet radio networks with spasmodic change of frequency which takes into account both handicaps of external sources and intersystem handicaps was offered.

I.  Introduction

Last decade development of economic activities of man is characterized by great increase of an information exchange. Existing cable networks do not meet constantly growing requirements, and their upgrade, in many cases, demands significant investments. Therefore, wireless technologies are applied to data transfer between removed networks more often. Radio networks of the standard 802.11 are most exploited now. In connection with growing number of sources of electromagnetic radiation in newly developed radio systems it becomes more complex to execute requirements on reliability.

II.  Main part

Using a method of frequency jumps in Ethernet radio networks the working range 2400 – 2483 МГц shares on 79 channels by 1 МГц. The standard [1] provides data transfer consistently on 22 switching of channels stipulated circuits. In each channel frequency modulation of the second or fourth level is used frequency depending on link speed. The standard 802.11 provides an opportunity depending on noise condition. As shown in work [2] speed and reliability are interconnected, therefore in the given work we shall count speed constant.

Reliability of transfer of the information depends on the ratio of capacity of a signal to total capacity of a handicap and noise and this it quantitatively estimated by allowable value of probability of a mistake.

For systems of a radio communication on influence on system two groups of sources of handicapes own handicapes of system and external handicapes are characteristic. In spite of the fact that all subscribers work on various frequencies, as a result within strip radiations and presence of collateral channels of reception the contribution of own system in noise conditions may be very significant.

III.  The conclusion

The offered mathematical model of a quantitative rating of reliability in Ethernet radio networks with spasmodic change of frequency, in particular under the standard 802.11, allows to define a bit mistake in each separate channel between each of two correspondents, depending on topology of a network, orientation of antennas of each subscribers, parameters of antennas systems, working wavelength, distance between subscribers, capacities of transmitters of users stations.

Джерело: Матеріали Міжнародної Кримської конференції «СВЧ-техніка і телекомунікаційні технології»