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RF-MAN
2013-03-24, 10:41 PM
what is the difference between 2 antenna in below picture at field of propagation of wave and frequency band and other things ?
how to propagation wave in space ? the sine form or not ?
whether when is propagation wave ,waves to form sine are integrated ?
all difference between below picture from frequency to capacity band and ........
please put your comment or share Knowledge about this.
very very very thanks
32052 32053
probabaja
2013-03-25, 03:12 AM
Left antenna: panel antenna
Right antenna: parabolic antenna
Left antenna (example):
- for GSM / CDMA,
- frequency 790 - 960 MHz
- typ. gain 18dbi
- typ. H beamwidth: 65°
- typ V beamwidth: 7°
Right antenna:
- for microwave link
- frequency: xx GHz (example: 4, 6, 7, 8, 10, 11, 13, 18, 23, 39 GHz ...)
- typ. gain 40dBi (1.2m, 10GHz band)
- beamwidth: < 2°
RF-MAN
2013-03-25, 12:56 PM
hi dear
all thing u say is right.
i want to know that how parabolic can transmit 16*2 capacity and panel antenna can't?
probabaja
2013-03-25, 04:12 PM
Capacity is bandwidth-depend, but capacity does not depend on type of antenna..
Shannon-Hartley theorem
http://upload.wikimedia.org/math/5/d/a/5da4ee296242ff06ad38fd97d1911cb3.png
where
C is the channel capacity in bits per second;
B is the bandwidth of the channel in hertz;
S/N is the signal-to-noise ratio (SNR) or the carrier-to-noise ratio (CNR) of the communication signal to the Gaussian noise interference expressed as a linear power ratio (not as logarithmic decibels).
indiaco
2013-03-26, 07:54 AM
hi dear
all thing u say is right.
i want to know that how parabolic can transmit 16*2 capacity and panel antenna can't?
I think Probabaja was really acurate, I would only add that the panel antenna is used to create a coverage area (a cell) and the parabolic antenna is used to create a "line" en between points in order to set a high capacity link.
Check the radiation patterns of them and it would become clearer.
About the capacity, it's got to do with the BW alocated in each case.
B.R.
N.
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