You want to use AP with WLC or AP alone ?
I will say use 2 Cisco ap as in normal mode and use 3rd AP as WGB.
mount this WGB on mobile vehicle. This WHB will communicate with these 2 APs.
http://www.cisco.com/c/en/us/support/docs/wireless/aironet-1200-series/68472-configure-wgb-00.html
*** I will recommend to use 1702 Cisco AP.
Regards
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