Re: Sensor Network
From: Jim Granville (no.spam_at_designtools.co.nz)
Date: Sun, 28 Mar 2004 12:22:04 +1200
Paul Carpenter wrote:
> On 27 Mar, in article
> firstname.lastname@example.org "Adnan" wrote:
>>Thank you for your responses. Following are some more details:
>>Price: Under US$100 / lock, that inclues the lock, the biometric
>>scanner, radio transciever, embeded system. (I know, its tough)
>>Power Requirements: Not an issue. This is for a hotel environment,
>>where this lock would be installed in every door. The power to operate
>>the electronic lock would be taken from within the room. The reason we
>>can't go for a "wired" comm. link between the server and the lock is
>>that doing the wiring for 500 locks is just too invasive, expensive,
>>disruptive and is prone to higher maintenance cost.
> As you are taking power from the room, you will also have access to another
> piece of wiring, the hotel PHONE system, see if you can piggy back a carrier
> onto that and using even cheap broadband microfilters (hidden away), you don't
> have to find places for aerials/hubs on each floor.
> The wiring is going to have to be hidden/buried for the power, so piggybacking
> a signal for comms down this that is then routed via the PHONE wiring, seems
> simpler to me.
If the phone co. agrees.. :)
Simpler still would be to use PowerLine modems, of the HomePLUG arena.
These use ADSL techniques to get some megabaud of spread sprectrum
comms, over wired power networks.
This is one supplier http://www.domosys.com/products/chips/