And they smell like butt. Why? Because that's where inmates cram 'em. So it looks like the Bloodhound here will be pointing directly to the backside of a lot of prison jumpsuits.
In all seriousness though, contraband mobile phones are becoming a major problem in prisons throughout the country. One solution, mobile phone signal jamming, has already been passed by the US Senate. Bloodhound is intended to be an alternative to jamming - a device that sniffs out mobile phone RF signals using a high-speed scanning multi-band receiver harnessed to a DF-Direction Finding Antenna.
The problem with all of this is that prison guards would each need a detector, and they could only get results when the mobile phones are actually in use. So, it seems like the best solution is still jamming mobile phones en masse. In that scenario, the FCC would be required to lay out rules and ensure that legitimate communications are not blocked, which negates Bloodhound's one major advantage. [BVS and PR Newswire via Coolest Gadgets]