Actually any good digital scanner now can pick up trunked radio conversations very well. There are a couple systems that they can't pick up, but the Uniden BC296D or 796D can do most. RadioShack has their own model too, the PRO96 if I recall.
The reason the antennas are so small is because the typical frequency of a trunked radio system is around 800mhz give or take. The antennas for this are comparable to mobile phone antennas. Back when the public safety systems were on CB frequencies you needed giant whips. When they were in the 156.000 Mhz range you could get away with a smaller whip, but now that they're getting near Ghz ranges the antennas have shrunk considerably. The other reason they're down to the size of Sirius antennas, is because you can shrink an 800mhz antenna down considerably when all you need it to communicate on is a very small range of frequencies.
Lastly, A field agent could talk to another agent 70 miles away pretty easily if there are enough towers in enough critical locations. Michigan has implemented this for their state police. A trooper in the UP can talk to a trooper near Detroit through this network of towers. Everything on their network can be picked up on a scanner for around 600 US dollars, with the exception of the encrypted communications.
Anything that is a combination of 2 or more of those three things you mentioned is considered "Strong" authentication. I'm not a fan of suspicion engines, but the future will have three-factor authentication that is less hassle than using an ATM is today. It's a ways off, and it's enough to make any privacy advocate's skin crawl, but the day is coming when the public will beg for it.
Don't believe me? Imagine a chip in your hand that replaces your wallet, your keys (house and car), all your passwords at work (and usernames for that matter), passwords at home. It would contain all your bank account information, state, national (global at that point?) ID, and medical records. Not only will the public sector push it hard, but the convenience level alone will make the average person beg for it. You'll need it when you get on the bus, walk into a store, walk into work, go to the doctor, etc..
Add a PIN number (not really even necessary to remain strong authentication) and it's just like an ATM transaction, minus a card. Only now it's three-factor. The implant is both something you are and something you have, and the PIN is something you know. Implants exist now that can sense blood pressure and other vitals, so cutting off someones hand for the implant isn't going to work. When this goes live there will likely be technology improvements in place to counter and discourage implant theft.
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Actually any good digital scanner now can pick up trunked radio conversations very well. There are a couple systems that they can't pick up, but the Uniden BC296D or 796D can do most. RadioShack has their own model too, the PRO96 if I recall.
The reason the antennas are so small is because the typical frequency of a trunked radio system is around 800mhz give or take. The antennas for this are comparable to mobile phone antennas. Back when the public safety systems were on CB frequencies you needed giant whips. When they were in the 156.000 Mhz range you could get away with a smaller whip, but now that they're getting near Ghz ranges the antennas have shrunk considerably. The other reason they're down to the size of Sirius antennas, is because you can shrink an 800mhz antenna down considerably when all you need it to communicate on is a very small range of frequencies.
Lastly, A field agent could talk to another agent 70 miles away pretty easily if there are enough towers in enough critical locations. Michigan has implemented this for their state police. A trooper in the UP can talk to a trooper near Detroit through this network of towers. Everything on their network can be picked up on a scanner for around 600 US dollars, with the exception of the encrypted communications.
Anything that is a combination of 2 or more of those three things you mentioned is considered "Strong" authentication. I'm not a fan of suspicion engines, but the future will have three-factor authentication that is less hassle than using an ATM is today. It's a ways off, and it's enough to make any privacy advocate's skin crawl, but the day is coming when the public will beg for it.
Don't believe me? Imagine a chip in your hand that replaces your wallet, your keys (house and car), all your passwords at work (and usernames for that matter), passwords at home. It would contain all your bank account information, state, national (global at that point?) ID, and medical records. Not only will the public sector push it hard, but the convenience level alone will make the average person beg for it. You'll need it when you get on the bus, walk into a store, walk into work, go to the doctor, etc..
Add a PIN number (not really even necessary to remain strong authentication) and it's just like an ATM transaction, minus a card. Only now it's three-factor. The implant is both something you are and something you have, and the PIN is something you know. Implants exist now that can sense blood pressure and other vitals, so cutting off someones hand for the implant isn't going to work. When this goes live there will likely be technology improvements in place to counter and discourage implant theft.
Of course, national ID has to happen first.