Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Announcements
Webcast-Catalyst9k
New Member

Antenna with multiple frequencies

Hi all,

Is it possible for an antenna to work on 2 different frequencies or channels simultaneously ?

15 REPLIES
Hall of Fame Super Gold

Antenna with multiple frequencies

Yes, there are dual-band antennas:  Antennas which can transmit both 2.4 and 5.0 Ghz band.

New Member

Antenna with multiple frequencies

You mean at the same time ? i think its not possible but just want to confirm it

New Member

Antenna with multiple frequencies

Sir kindly confirm

Hall of Fame Super Gold

Antenna with multiple frequencies

Sir kindly confirm

Jonn,

I have to sleep sometimes. 

Look at the data sheet of the Cisco Aironet 2.4-GHz/5-GHz MIMO 4-Element Patch Antenna (AIR-ANT2566P4W-R).

This is a DUAL-BAND antenna.  If connected to the right AP, like 1600/2600/3600/3700 this AP can transmit both 2.4Ghz and 5.0 Ghz simultaneously. 

New Member

Antenna with multiple frequencies

Sir, does it mean its possible to have one antenna working on 2 channels of 2.4 Ghz band simultaneously also ?

Hall of Fame Super Gold

Antenna with multiple frequencies

Sir, does it mean its possible to have one antenna working on 2 channels of 2.4 Ghz band simultaneously also ?

No and because it doesn't make any sense.

You can only attach each patch antenna to ONE AP only.  So if your AP is transmitting at Channel 11 (for example), how do you expect the same AP to transmit Channels 1 or 6? 

New Member

Antenna with multiple frequencies

Then Sir, 2.4Ghz  and 5 Ghz are 2 different frequencies. How come an antenna trasmit on both these channels at the same time ?

Sir also what did you meant by patch antenna

Hall of Fame Super Gold

Re: Antenna with multiple frequencies

Then Sir, 2.4Ghz  and 5 Ghz are 2 different frequencies.

Ok, you are definitely lost.

Don't think of 2.4 Ghz and 5.0 Ghz as one "frequency".  They are very, very different.

2.4 Ghz and 5.0 Ghz operate at two distinctly different frequency.  Look at your radio or truck radio (CB).  Have you heard of car radio operating in AM and FM band?  This is the main difference between 2.4 Ghz and 5.0 Ghz.  They are different bands, 802.11b (2.4 Ghz) and 802.11a (5.0 Ghz).

The data sheet I posted in my earlier response is talking about a single unit antenna with 4 pig-tail RP-TNC.  Two sockets go to the 2.4 Ghz socket and the other two goes to the 5.0 Ghz socket. 

Because they are connected separately, the AP can transmit both bands simultaneously.  Now each band can be "chopped up" into multiple channels.  2.4 Ghz can have 13 to 14 channels but ideally, you can only have three non-overlapping channels to use.  See below.

New Member

Re: Antenna with multiple frequencies

Sir i think my wordings are confusing the matter. I will try to rephrase

Sir according to my understanding, since 2.4Ghz and 5Ghz are different frequency ranges, how come an antenna radiates for them simultaneously ? its just like saying a switch port working in ethernet and token ring mode at the same time which is not possible. I think there are multiple antennas inside a single antenna closure ? is it possible ?

Hall of Fame Super Gold

Antenna with multiple frequencies

I think there are multiple antennas inside a single antenna closure ? is it possible ?

Yes.  This is possible.  The link I've posted is for an dual-band antenna.

New Member

Re: Antenna with multiple frequencies

Then why its impossible for an antenna to work on 2 different channels of 2.4GHz simultaneously ?

Hall of Fame Super Gold

Re: Antenna with multiple frequencies

Then why its impossible for an antenna to work on 2 different channels of 2.4GHz simultaneously ?

Jonn,

We are going around in circle here.

You cannot find an AP that can transmit two different channels on a SINGLE BAND.   2.4 Ghz is a single band.  5.0 Ghz is another single band.

Do you see the difference?

New Member

Re: Antenna with multiple frequencies

Sir ultimately they are frequencies right ?

New Member

Re: Antenna with multiple frequencies

I guess i am too confused to ask the question properly.

Thanks for your support

Hall of Fame Super Gold

Re: Antenna with multiple frequencies

2.4 Ghz is a frequency which is called the 802.11a radio band.

5.0 Ghz is a frequency which is called the 802.11b radio band.

2.4 Ghz/802.11b has 13 (or 14) channels. 

821
Views
0
Helpful
15
Replies
CreatePlease to create content