[3] body chapter 7 x826.docx

7/25/2019 [3] body chapter 7 X826.docx

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Chapter 7: BTS Site Visit

I visited a number of indoor and outdoor BTSs. In indoor BTS all parts of it is separated into aroom. But in outdoor BTS all parts are along with into a box except the antenna.

Major parts of BTS:

. !ectifier

". Batter#$. %nits

&. ' channels

(. Sensors

). *ode+", - $,

7. !!%+!emote !adio %nit+different for ", - $, +) !!% in BTS/. 0ntennas+$ for ", - $ for $,

1. 2icrowave antenna.'tc...

Fig 7.1: Basic Structure of an Outdoor BTS.

7.1. Visit to Outdoor BTS

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0n 5utdoor BTS is li6e a double door fridge a box where all the e8uipments are nicel# settled.

Built9in air9condition inside. In right side part there are batter# rac6s and in left side part there

are other e8uipments or vice versa. Fig 7.1 & 7.2;

Fig 7.2: Different parts of an outdoor BTS are shown.

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Fig 7.3: Rectifier and odu!e units.

Rectifier: It converts 0C +0lternating Current power into


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Sensors: There are different t#pes of sensors in a BTS these are

Smo6e Sensor

=ater Sensor

Temperature Sensor

Node (2 ! "#:It is the hardware that is connected to the mobile phone networ6 that

communicates directl# with mobile handsets. In contrast with ,S2 base stations *ode B

uses =CT


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Fig 7.+: DDF of a BTS

$$%:


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Fig 7.7: Batter, Ban( -Outdoor BTS.

There are "& units of batter# in a batter# ban6. In each tra# there are / units of batter#. $ tra#s in

a batter# ban6 total of "& units.

7.2. Visit to ndoor BTS

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Fig 7./: 0icture of an indoor BTS.

In the picture Fig +./; the left part is the *5


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Fig 7.: nterna! Structures of a uawei ndoor BTS -2$.

)o*er S&ste+: 3ower S#stem is one of the main sectors in a telecom organiation. Input power

of Telecom e8uipment ma# be:


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The purposes are:

To ensure constant


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onl# be charged b#


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Fig 7.12: #OD6 B of a ndoor BTS.

Node B: 0 BTS in $, is called *ode B. It is a term to denote a base station in %2TS

terminolog#. Traditionall# the *ode BEs have minimum functionalit# and are controlled b# an!*C +!adio *etwor6 Controller. ?owever this is changing with the emergence of ?igh Speed


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7.". BTS /ntennas

/ntennas: In all BTS directional antennas are used. 5ne is microwave antenna which is used for

microwave transmission between BTS to BTS or BTS to BSC>2SC or vice versa. Three sector

antennas are used for BTS to 2S communication which wor6s on a desired fre8uenc# for

example 1AA2? or /AA2?. These $ antennas are set "A angels to each other which is

mesured b# compus mesured from A +north called aimuth angle. These antennas are also

tillted a perticular angle which is mesured b# the tillting mitter. It depandes on the coverage area

the antenna is going to cover as itEs networ6ing area. 0s fre8uenc# increases the antenna sie

decreases.

Fig 7.13: 3 a, faced %ntennas.

In ever# wa# there is a ,S2 1AA ,S2 /AA and =C


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RRU: 0 remote radio unit +!!% in a radio base station s#stem can include a c#clic prefix +C3

module with a C3 adder for downlin6 channel processing and a C3 remover for uplin6 channel

processing. The !!% can be configured to communicate with a base band unit +BB% via a

ph#sical communication lin6 and can communicate with a wireless mobile device via an air

interface. Fig +.12;

!emote !adio %nits are generall# installed in towers and are controlled b# a controller placed

inside a closed shelter on the ground nearb# the tower. The connection between the !!% and the

controller is generall# optical. The !!% and the controller form the BTS or Base Transceiver

Station which is widel# used in cellular communication.

!!% are different for ", - $, but same !!% wor6s on different fre8uenc# +1AA2? -

/AA2?.

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[3] body chapter 7 x826.docx

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