RFL Communications 21 Sub-MUX Instrukcja Użytkownika Pobierz pdf (Strona 26)

Solutions for an evolving world.

Analog Channels

Analog Microwave channels

• i.e. Voice Channels, Video, Data

• Parabolic antenna

• Point to Point/Narrow Beam

• Alignment is important

• Advantage

• the high frequency of microwaves gives the microwave band a very large

information-carrying capacity; the microwave band has a bandwidth 30

times that of all the rest of the radio spectrum below it

• A disadvantage

• is that microwaves are limited to line of sight propagation; they cannot pass

around hills or mountains as lower frequency radio waves can.

• Weather

Leased Telephone Lines

• A leased line is a service contract between a provider and a customer, whereby the

provider agrees to deliver a symmetric telecommunications line connecting two or more

locations in exchange for a monthly rent (hence the term lease). It is sometimes known

as a "private circuit

• 2X pair of copper twisted wires (TX/RX)

• a leased line is always active,(meaning no service interruptions due to Phone

company testing)

• In the U.S., low-speed leased lines (56 kbit/s and below) are usually provided

using analog modems.

• Generally ordered with specified attenuation. (i.e. 10db)

1 2 ... 21 22 23 24 25 26 27 28 29 30 31 ... 40 41

Brak uwag

RFL Communications 21 Sub-MUX Instrukcja Użytkownika Strona 26