Unbound Media/Unguided Media

Unbound Media
        orUnguided Media:

Unguided Media: It is one that does not guide the data signals instead it uses the multiple paths for
transmitting data signals. In this type the data cable are not bounds to a cable media. So it is called
“Unbound media” basically there are 2 types.

a) Microwave 
b) Satellite Technology.  

a) Microwave:  

Microwaves are radio waves that are used to provide high‐speed transmission. Both voice and data can be transmitted through microwave. Data is transmitted through the air form one microwave station to other similar to radio signals. Microwave uses line‐of‐sight transmission. It means that the signals travel in straight path and cannot bend. Microwave stations or antennas are usually installed on high towers or buildings. Microwave stations are placed within 20 to 30 miles to each other. Each station receives signal from previous station and transfer to next station. In this way, data transferred from one place to another. There
should be no buildings on mountains between microwave stations.

Advantages:
1. It has the medium capacity
slightly higher than “Bound Media".

2. Medium cost.

3. It can cover longer distance that cannot be possible by bound media.  

Disadvantages:
1. Noise interference is more.

2. Since it uses less susceptible
signal so it has got greater influence from rain & fog.

3. It is not secure & reliable. 

b) Satellite Communication:

Communication satellite is a space station. It receives microwave signals from earth station. It amplifies the signal and retransmits them back to earth. Communication satellite is established in space about 22,300 miles above the earth. The data transfer speed of communication satellite is very high. The transmission from earth station to satellite is called uplink. The transmission from satellite to earth station is called downlink. An important advantage at satellite is that a large volume of data can be
communicated at once. The disadvantage is that bad weather can severely affect the quality of satellite transmission.

Advantages:
1. Low cost per user (for pay TV)

2. High Capacity

3. Very large coverage area.  

Disadvantages:

1. High Installing & managing cost.

2. Receive dishes & decoders required.

3. Delays involved in the reception of the signal.