I use this on my van
http://www.wpsantennas.com/index.asp...ROD&ProdID=470
* Operates simultaneously on 7 bands (AMPS/Cellular, IDEN, GSM, GPS, DCS, PCS, UMTS, ISM/WiFi)
* Compatible with all US Cellular and PCS providers, supports overseas frequencies as well
* Multiple NMO mounting options are available (sold separately)
* Metal ground plane required
* Patented Field Diversity US Patent Numbers 45,977,931 and 6,292,156
* Patented PC Board radiator
* Phantom patented true field diversity design ensures uninterrupted transmissions in urban canyons and rural drop off areas - counteracts signal fading in reflective or mobile environments
* 3dB MEG gain outperforms a 3dB whip in many applications
* Solid construction: ABS material is injection molded directly around the solid brass insert and all silver soldered joints
* Specified by public safety, military, utility and transportation providers and installed on Apache, Black Hawk and Chinook helicopters and Humvee and Bradley military vehicles around the world.
I have actually seen this on Offical vehicals as well.
it's only an inch tall and 3db, but I would think in a building a tall antenna wouldn't have enough "room" for it's pattern