Selasa, 28 September 2010

Data Communication Between Computers

Data communication between computers via a cable modem voice.
The speed of the modem is highly dependent on the quality of the channel. If one is an interruption in the channel, then the velocity distribution will be minimized by the modem (dynamic). What is important in calculating the data communication is throughput (effective channeling of bps).

Senin, 27 September 2010

Local Channel Radio Access

Local channel access radio is a local network that uses radio. Also commonly called WLL (Wireless Local Loop) radio system is used only to replace the cable between the central and customers.

Radio frequency division following:
  1. 30-30     KHz  VLF
  2. 30-300   KHz  LF
  3. 0.3 to 3  MHz  MF
  4. 3-30      MHz  HF
  5. 30-300  MHz  VHF
  6. 0.3 to 3 GHz   UHF
  7. 3-30     GHz   SHF
  8. 30-300 GHz   EHF
Radio transmission media
  1. Amplifiers convert electrical signals into an electromagnetic wave signal (TX) or vice versa (RX)
  2. Antenna reflector serves to direct the beam
  3. Problems are always addressed in the antenna is the strengthening and direction angle
  4. Between transmitter and receiver because there is always a loss of receiving antenna can not take all the  power emitted
With technological developments, the receiver can be smaller and more sensitive reception system. This development allows the receiver to move in a restricted area within the meaning of customer aircraft can not work outside the area because it is not registered.

RBS function as a radio transceiver terminal on the side of a telephone exchange. At home functioning radio receiver to receive / send radio signals and convert signals into the phone.

The advantages of using the local network:
  1. Reaching a network that is difficult to reach.
  2. Flexible in the number of customers served
  3. Lower operating costs
  4. The price is cheaper because a single radio device can handle many customer
  5. Faster installation
  6. Good for new areas
  7. Could join the local central plain, can also stand alone depending on the number of subscribers RBS.
Weaknesses Using Local Network:
  1. Bandwidth limitations of radio frequencies that can be served
  2. In general, fixed antenna subsciber with BTS should be able to see each other each other (the antenna should be placed high).

Basic Telecommunications


The definition of telecommunications is to exchange information on long-distance relationship, where the exchange of information (where there is a change "format information") On long-distance communication links that occur in electrical / electronic where there are several examples of the types of information are:
Sound = Telephony, voice and image = vidiophone, writing in print = Telegraphy / Telex, Document = Telefex, Pictures Television, Writing and sounds = Multimedia.


Telecommunications System (SISTEL) is a unity consisting of parts called subsystems which interact to achieve specific goals.

SISTEL consists of:
1. Sender, transmitter, source info
2. Receiving, goals
3. Media transmission

SISTEL components consist of:
1.Terminal Equipment (TE)
2. Switching Equipment (Central)
3. Transmission Line (Cable, Radio and Satellite)


Terminal Equipment (TE) as a device ynag is a source of information which you want to convey to a specific destination and also can be a telephone, computer, etc., act as a sender and receiver.

Switching Equipment (Central) As a means of connecting between a single channel with a single channel so that the channel is carried by the channel to the destination.

Terminal device, the device at the customer's content (CPE) functions to:
1. Calling and receiving alternately
2. Calling it
3. Receive only

Antenna Microwafe


Microwafe antenna is an external device that has the task to transmit the signal conduction from one place to another place with a certain capacity, these devices have different sizes and types in accordance with the desired amount of capacity.
example: for a distance of 1-3 Kilometers good wear size 0.3 meters diameter antennas, while the distance of 4-6 kilometers to good use 0.6-meter diameter antenna size, for a distance of 7-9 kilometers antenna size of 1.2 meters and so on.


In addition to the antenna device is supported by other devices in the call ODU (Out Door Unit) ODU is useful to operate and emit a signal from the device commonly called IDU (In Door Unit) of IDUs are emitting a signal flow and the capture by ODU and drain again from ODU to the antenna of the antenna be a signal that connects the region to the other regions.

Sabtu, 25 September 2010

Cellter


Cellter is a special place to put the transmission device to a temperature range and damage the environment, in order to keep the device always works well



Above is a drawing tool electric rack, transmission racks and racks DDF (E1 cable).


Above is a picture of two BTS device at the front and the rear is a transmission device and rack DDF.

This is a picture that there is a small device inside Cellter these devices have the task of each character, from where a central control which operates the antennas that emit signals.

Sabtu, 04 September 2010

Presence Of Telecommunication Towers

Tower is a means for mounting a telecommunications device that much in use today, although many are also some who use other means, each operator vying to get a strategic place for the installation of towers, because of the strategic place that many more customers possible using the cellular operator.

Unfortunately in the year 2010 was for the installation of towers, especially in Indonesia have been restricted because it has so many that have been installed and therefore the government has begun to conduct joint tower system, so any single tower unit can be used for many operators who want it.

Many of the benefits with the tower of which are:

  1. Place a secure installation of telecommunications equipment
  2. Safe from dangerous lightning
  3. With the installation of towers to add new jobs to the contractor concerned.
  4. Telecommunication system can be connected between areas
In addition, many also caused a negative impact on them:

  1.  Does not irregular arrangement of the installation of towers would ruin the atmosphere of the order of city impact
  2.  The system is not good ground can cause a lot of danger of lightning tower over the surrounding environment


Once meant for developing countries would be establishment of a good communication and safe, so what would be aimed at implemented quickly and safely.

Tower foundation will determine the strength of a pole tower, a strong foundation which will determine how big a force to be in charge of the tower while also the power poles are also very big influence on how the burden that must fit on the tower.
Why do the pole tower should be painted?
because the tower is a tall pole sign to be in love so as not to cause harm and the thing that does not want another.
And each pole has a higher tower is different in because of different places, depending on soil structure is bumpy or not.
For example: In the mountains must have a high tower in because in sure a lot of barriers.
For urban areas are certainly not a lot of barriers that impede the flow that emits signals from one tower to the next tower.