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New Member

1232 AP upgrade to 1602E, having coverage issues

Hi,

A customer of mine wants to upgrade their existing 1232 (autonomous) APs to ones that support "N" radio speeds.  Today we replaced an existing 1232 with one of these:  AIR-SAP1602E-A-K9 

After setting it up with IP and security (AES CCMP + TKIP) we were able to connect to it with no problems using out lap tops.  Iphones and IPads had trouble connecting and staying connected however--this may have been related to TKIP being enabled.  We did check and uncheck the box "mixed" in the 2.4 Ghz radio setting page, but it didn't seem to make any difference.

When we swapped it with the 1232, we saw that the coverage was quite a bit less than that which we had with the  old 802.11 b/g radio. The 1232 was able to get a signal through the floor to offices directly above it.  The 1602 pretty much got nothing through even though it was installed in exactly the same location as the 1232.  Since the 1602 supports the b/g radio standards in addtion to the "n", I would think that it would at least give us some coverage through the floor, like the old 1232 always did.  

After seeing the coverage issues, we made sure that the 2.4 Ghz radio tx / rx power levels were set to their default "max" levels.  We then used an older Cisco a/b/g PCMCIA card with Cisco's  old ACU and found that the SNR through the floor was 10 db or less at best.  The SNR for the 1231 was in the high mid to high 20s when we checked it through the floor.

Are we missing a setting or something that might be causing the signal to be so weak? 

About a year ago we installed a bunch of 2602s (autonomous) that worked very well in a large warehouse. I'm starting to think that we went with the wrong AP.  

Total number of users for this install will be around 15.  Most will be browsing the web and doing 5250 terminal emulaton.

Any help or ideas on this problem would be greatly appreciated.


Thanks

4 REPLIES
Hall of Fame Super Gold

What antenna are you using

What antenna are you using for the 1602E?  

Welcome to the new age..

Welcome to the new age..  math.

The internal .11g transmitter in the 1231/32 has a maximum power of 15 dbm and always transmits on the single antenna with the strongest receive signal.  The antenna was a little half-wave dipole.

The individual .11g transmitters in the 1602 have a maximum power of 17 dbm each.  The entire unit is limited to 22 dbm maximum, which occurs when all 3 transmitters are active (3 antenna mode).  When all 3 antennas are used together, the individual transmitters are powered back to 7.3 dbm each.  Now things get a bit murky to me here..  I don't know if the 'data' transmitted on the three streams (antennas) is identical or not.  Lets say NOT.  So your single stream client can only make use of resulting 7.3dbm of power.  If you change the AP to single antenna mode the power should double..  from the one antenna and be 2 dbm stronger than the original 1231/32 setup.

 

New Member

Thanks for the reply.  We'll

Thanks for the reply.  We'll try it out with only one antenna and see if coverage improves.

I'll post results.

New Member

Antennas are three, P/N is

Antennas are three, P/N is AIR-ANT2524DW-R

Cisco 2.0 dBi dual band (2.4 GHz and 5.0 GHz) dipole antennas.

What if we turn off the "A" radio and use two 802.11b/g whip antennas?

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