Public hotspot - Choosing the right antenna.

[francisco.custodio]

Hi guys!

I have a project to make a public wireless internet access network. I'm going to use 1200's ap's for access and 350's to make the wireless backbone to connect the ap's to the main site. For the bridges i'm going to use yagis...nothing wrong here. For the AP's I'm not sure...2.2dbi dipoles? or an omni mast mount antenna? The AP's will be closed on a box with the dipoles inside...or with external mast mount omni's. Advices are welcomed.

Cheers!

[EPHRAIM MANI]

hi

the antennas should preferably be placed outside the box because insiade the box u are placing an obstruction . and yes you can also use cisco 6dbi omni directional antenna which also ive better range

[nraza]

can we use 12 dbi omni antenna with 1200? and how far will this configruation cover the distance?

[zappolinom]

Hi,

you have to use the Cisco Aironet Calc Tool wich is downloadable for Partners.In the Tool you have to select your Regulatory Domain(FCC or ETSI etc.) you select then the PCI350 Card on booth Sides. Then select the desired Data rate (11MB, 5,5 etc.), Antenna 1 wich represents your Hotspot AP is to be set to the desired antenna Antenna Gain(12dBi Omni) at the other side Antenna2 you select other and enter the for other Antenna Gain enter here-> antenna Gain of 2,2 dBi for the Rubber Ducks (AIR-ANT4941).

Select the Cable type for both sides at the Site 2 select no cable as you want to emulate the PCMCIA Card (set also for site 2 the Power Level to 50 mW if ETSI or 100mW if FCC).

For Site 1 you could select the Cable types based on the length that you could purchase from Cisco or if you have an alternative then enter other and to the field below you enter the cable loss in DB per 100ft of Cable length(this is normally provided by Cable manufacturer). And as result you wiull see the distance you cover in miles otr meters with line of sight. If you have Walls or other obstructions at the Hotspot then you reduce this number. But dont forget an Site Survey is necessary (especially the Site Survey conducted with Aironet PCMCIA Cards needs to be done i active mode.This means you generate packets in the ACU send it to the AP the AP holds them an send them back to your NIC. This could be tuned to Continous link test so after 100 % of of succesfull transmit then will be restarted. You also have to select here the desired Datarate and the desried Packet Size. Dont forget with statc 1450 Byte Packets the troughput is easy for AP but if you turn down to smaller you will see the AP a little bit more loaded.