3G EIRP - Computation

[chronix_ray]

Hi All,

Question: In computing the 3G EIRP, do we use CPICH power only or the whole RRU power rating?

Br//Kinghttp://www.finetopix.com/vbb/images/icons/icon7.gif

[kin12345]

Hi All,

Question: In computing the 3G EIRP, do we use CPICH power only or the whole RRU power rating?

Br//Kinghttp://www.finetopix.com/vbb/images/icons/icon7.gif

it should be total rru power.

[chronix_ray]

Thanks! But im still confused because other operators use CPICH power in getting the EIRP.

[kin12345]

Thanks! But im still confused because other operators use CPICH power in getting the EIRP.

that can be the coverage boundary EIRP where you set the coverage threshold.

[chronix_ray]

So it means that if we use the RRU power, we are computing for the maximum coverage the NodeB can serve. Thanks!

[kin12345]

[QUOTE=chronix_ray;156974]So it means that if we use the RRU power, we are computing for the maximum coverage the NodeB can serve. Thanks![/QUOT

The rru power probably it used to calculate the radiation level. I am not sure about the maximum coverage though since we are using 10 to 15% of the rru power for the cpich.

[paladin3056]

Follow up question:

Is there a formula for getting the EIRP which would relate the RRU power and the CPICH? Thanks!

[kin12345]

Follow up question:

Is there a formula for getting the EIRP which would relate the RRU power and the CPICH? Thanks!
eirp=tx power- loss +antenna gain.

[dekili]

You should use whole RRU power for getting radiated power. Operators would use CPICH because they are interested in quality of the coverage and the network. In the case of health hazards, ICINIRP norm etc., you have to use whole radiated power.
Cheers...

[chronix_ray]

Thanks for the reply. Actually we are computing for the EIRP on IBS DAS. In practice, what power should we use?

[dekili]

Depends on the venue. For example, for a shopping centre, for directional antenna, I have EIRP in ranges from 5 to 10dBm. For stadia and different venues that are much bigger (antennas are more away from users) it is no less than 8dBm. For small venues and omni antennas it can go down to 2dBm EIRP. It all depends on the venue, your antenna spacing and what is your strategy in covering...

[freakturd06]

Does anyone here has an excel template to compute every DAS EIRP based in a network trunking diagram. Just need to input passive/active component type,feeder cable length, etc.

[D33T0X]

For coverage simulations CPICH power should be used

[chronix_ray]

Depends on the venue. For example, for a shopping centre, for directional antenna, I have EIRP in ranges from 5 to 10dBm. For stadia and different venues that are much bigger (antennas are more away from users) it is no less than 8dBm. For small venues and omni antennas it can go down to 2dBm EIRP. It all depends on the venue, your antenna spacing and what is your strategy in covering...

Thanks! I get it. Its just the operator has a required level of EIRP in every antenna for a DAS (omni). Example: In every design. EIRP in 3G should be no less than 8dBm.

[kin12345]

Thanks! I get it. Its just the operator has a required level of EIRP in every antenna for a DAS (omni). Example: In every design. EIRP in 3G should be no less than 8dBm.

It is all according to the FCC guideline related to the health issue. In a specific frequency band, it has a given limit mw /m^2. You can do a search in this area.

[chronix_ray]

Thanks Kin!http://www.finetopix.com/vbb/images/icons/icon7.gif

[kin12345]

Thanks Kin!http://www.finetopix.com/vbb/images/icons/icon7.gif

hehe no problem i think if you use the thanks button is more than enough. You do not want to be banned man.

[aljfresco]

CPICH only

EIRP = CPICH-loss+gain

[da_manole]

For coverage you should keep only CPICH power .