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New Member

1300 wireless issue

hi all

i have a 1300 series AP/BR.

part no:AIR-BR1310G-E-K9-R (ETSI)

my external antenna is "AIR-ANT24120" 12dbi.Bcoz of some TRA issues i'm forced to use 5.725-5850.From TRA i got the instruction that, if you put 12 dbi or 13.5 dbi antenna the maximum power is should not exceed " 2W max.mean EIRP".

20 dbm/Mhz max. mean EIRP density.

so in this case how can i proceed with

1300 AP/BR. will this unit support 5.7 band.i need to change this unit? please give your suggestions.

Regds

Binoy.

3 REPLIES
Green

Re: 1300 wireless issue

To complete the calculation, it's necessary to know how much of what kind of cable is connecting the AP to the antenna (to calculate loss of the "intentional radiator").

For example, if you have 50 feet of coax that's rated at 6db loss per hundred feet, you are introducing about 3db f loss (then add another ~.25 db loss for each connector - AP-Cable-arrestor-cable-antenna).

In the above example, if the AP was putting out 20mw (13dbm):

50 feet of coax@ -6db/100 feet - -3db

four connectors @ -.25db ------- -1db

antenna @ 13.5db --------------- +13.5

Total gain: +9.5db

9.5db = 3db + 3db + 3db +.5db

Starting with 20mw (13dbm):

20mw * +3db = 40mw (16dbm)

40mw * +3db = 80mw (19dbm)

80mw * +3db = 160mw(22dbm)

.5db = who cares ;-}

dbm = db gain relative to 1 milliwat (mw)

2W = 2000mw = 33dbm

100mw = 20dbm

Here's a link to a mw/dbm calculator.

http://www.analog.com/Analog_Root/static/techSupport/designTools/interactiveTools/dbconvert/dbconvert.html

There's also a dbm/mw conversion table in the WebGUI of the AP (in the "Interfaces" screen where you'd adjust your power).

Short version:once you have the total gain of the system (connectors(-), coax(-), arrestor(-), antenna (+)), adjust your output power to stay below your local max Effective Isotropic Radiated Power (EIRP).

Good Luck

Scott

New Member

Re: 1300 wireless issue

hi scott thanks for your time.

scott my situation i will explain it to you.

i have 2 1300 series units.with 2 types of antennas.

12 dbi and 13.5 dbi.from TRA i got the information that 1300 unit is ok, but when it comes to the external antenna they are saying it's transmission power is more.

according to TRA people, transmission power should not exceed 2watt max.mean E.I.R.P

how can i utilise my 1300 & 12 dbi and 13.5 dbi antenna's for this.

if i want to go for 5.x Ghz will this 1300 support?

or i need to go for 1400, will this 1400 support 5.x Ghz?

Regds

Binoy

New Member

Re: 1300 wireless issue

The 1300 series bridge supports B/G radio, which is in the 2.4 GHz range. If you wanted to use 5.x GHZ, you would need an A radio. This is used in the 1400 series.

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