Controller Based WLANs

WHAT IS EIRP AND HOW IS IT CALCULATED

Environment : This article applies to all Aruba controllers and ArubaOS versions.

 

Effective Isotropic Radiated Power (EIRP) - Is the amount of power that a theoretical isotropic antenna (which evenly distributes power in all directions) would emit to produce the peak power density observed in the direction of maximum antenna gain . EIRP can take into account the losses in transmission line and connectors and includes the gain of the antenna.

 

The EIRP is often stated in terms of decibels over a reference power emitted by an isotropic radiator with equivalent signal strength. The EIRP allows comparisons between different emitters regardless of type, size or form. From the EIRP, and with knowledge of a real antenna's gain, it is possible to calculate real power and field strength values.
 
Formula to calculate
===================

 

EIRP = Tx RF Power (dBm)+GA (dB) - FL (dB)

 

Explanation
==========
 
Tx RF Power :RF power measured at RF connector of the unit
 
GA :Antenna gain
 
FL : Feeder loss(cable loss or any other loss)

 

 

show ap bss-table  (This command will show the EIRP value for the Ap)
 
 
fm (forward mode): T-Tunnel, S-Split, D-Decrypt Tunnel, B-Bridge (s-standard, p-persistent, b-backup, a-always)
 
Aruba AP BSS Table
------------------
bss                ess           s/p   ip             phy   type  ch/EIRP/max-EIRP  cur-cl  ap name                    in-t(s)  tot-t    mtu   acl-state  acl  fm
---                ---           ---   --             ---   ----  ----------------  ------  -------                    -------  -----    ---   ---------  ---  --
d8:c7:c8:3c:f7:51  babson        0/10  172.16.100.44  a-HT  ap    48-/16/16         0       b-yukon-3                  0        35m:58s  1500  -          1    T
d8:c7:c8:3c:cb:62  roam1         0/10  172.16.100.74  g-HT  ap    1/20/20           0       c-434                      0        38m:57s  1500  -          47   T
d8:c7:c8:3c:b5:31  babson        0/10  172.16.100.62  a-HT  ap    157+/20.5/20.5    0       c-s122                     0        45m:18s

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Last update:
‎07-11-2014 08:57 AM
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