Micro wave signal powers

[Y.SAI SARASWATHI]

I read that less power is required to transmit micro wave signals,explain me about it,
Because micro waves have higher frequencies which can carry data at faster data rates it means that they have higher energy in them implies that they carry high powers .....
Correct me if i understand it in wrong way,
so confused help me.

 

[juni1122]

i think its because they are highly directional

 

[kavea]

If you take an NRZ encoding and you want to send '101' , '1' state will be shorter with high frequencies. Higher the frequency shorter is 'on' states, so less energy is needed. On the other side , high frequencies suffer from higher transmission losses that needed (depends on distance) to be compensated.

 

[Y.SAI SARASWATHI]

Thank you but all are answering in different way why do microwaves require less transmission power ,is this statement true?
please answer in general terms it may not be related to any digital communication technique.

 

[chuckey]

Microwaves require less active gain because the aerials have 50 dB gain compared to a dipole. So on a link could be 100 DB of aerial gain for free
Frank

 

[Y.SAI SARASWATHI]

Microwaves require less active gain because the aerials have 50 dB gain compared to a dipole. So on a link could be 100 DB of aerial gain for free
Frank

I did not understand your post ,please elaborate it.(especially aerial gain)

 

[FvM]

see https://en.wikipedia.org/wiki/Antenna_gain

 

[chuckey]

Imagine a single spot in space that can transmit RF power equally in all directions. This is an isotropic radiator. A common aerial is a dipole, which is two wires end to end with the signal in or out taken at the two connections in the centre. When the overall length is exactly 1/2 of the wave length used, then its called a dipole. This transmits and receives signals at right angles to the centre all the way around, but not in line with its ends. Its like a dough nut around the aerial. Because of the high frequency a dipole becomes very small, so a parabolic dish is used instead. This focusses the incoming and outgoing RF collected over its total area to a dipole at its centre. This gives it its "gain" over the basic dipole. The aerial is the familiar satellite dish and acts like an optical lens.
Frank