Sensors Without Batteries

Comments

• 	Invisible Sensors Guest (Brad Wang) on 05/15/2006 at 12:00 AM
  Posts: 1	So is throwing out the batteries used for making the sensors "invisible"? If such radio energy can be used to place batteries in other fields, won't that be good? Rate this comment: (Reply)

• 	[no subject] Guest (Karl G. Schick) on 05/15/2006 at 12:00 AM
  Posts: 1	Why do you make so difficult to print out articles? I'm sure there is a simpler way. Rate this comment: (Reply)

  • 	x Guest (x) on 05/15/2006 at 12:00 AM
    Posts: 1	there's a print link on the right-hand nav. looks like it works quite well, though it create an extra page, with the article on the second page (in my case). Rate this comment: (Reply)

• 	energy, power, voltage Guest (ms) on 05/15/2006 at 12:00 AM
  Posts: 1	Voltage has nothing to do with energy. Power is energy per unit time. So the phrase "that much energy" makes no sense. Rate this comment: (Reply)

  • 	Voltage Guest (Joe) on 05/16/2006 at 12:00 AM
    Posts: 1	Isn't voltage 'energy' per unit of electrical charge ? Rate this comment: (Reply)

    • 	Voltage Guest (Hayes) on 05/16/2006 at 12:00 AM
      Posts: 1	Voltage is not energy. Proximity to the reader's restricted e-m field will increase the voltage realized at the RFID device. A minimum voltage is req'd to operate the components in the device. 1.8V can be realized at a greater distance than 3.0V. Rate this comment: (Reply)

      • 	Voltage Guest (Klc) on 07/30/2006 at 12:00 AM
        Posts: 1	Voltage is basically the force of the electron flow - Think pressure. This is half of the story when looking at energy/work. voltage x amperage (a measure of the amount of electrons, think volume) = energy/work Rate this comment: (Reply)

• 	How soon will NSA adopt this technology Guest (Paranoid) on 05/15/2006 at 12:00 AM
  Posts: 1	They're already monitoring all our calls and emails, so obviously this it the next step - implanting them in everybody when they go through customs. Rate this comment: (Reply)

  • 	NSA Guest (Powernoid) on 05/16/2006 at 12:00 AM
    Posts: 1	Why customs? They'd fit easily into a Twinky or Oreo. Bon apetite. Rate this comment: (Reply)

• Josh Smith is all wet! Guest (Dick Caro) on 05/15/2006 at 12:00 AM

  Posts: 1

  Mr. Smith clearly doesn't understand how passive RFID tags are "powered." They are powered by the electromagnetic energy generated by the RFID reader, not from solar, vibration, motion, or thermal sources. The reader's EMF field generates enough power that is picked up by the antenna on the RFID tag which then modulates the reader's query with the ID information on the tag. If there is no reader in the near-field, there is no power and the tag cannot do anything. This is NOT a solution for wireless sensor network that need power for their sensor over a longer time period than the field of a reader. Rate this comment: (Reply)

  • dick caro is all wet Guest (Dick Caro is all wet) on 05/15/2006 at 12:00 AM

    Posts: 1

    Mr. Caro clearly doesnt understand how to read. "One way to achieve this sort of ubiquitous computing is to disperse tiny sensors that measure, for instance, light, temperature, or motion." doesnt say that the rfid tags are "powered" by solar, vibration, motion, or thermal sources....nope not at all....its saying that sensors to monitor these things could and most probably will become common....and the rest of the article that just as as an "RFID tag which then modulates the reader's query with the ID information on the tag"....a microprocessor could simularly modulate the data...stealing power from the readers induced current. Rate this comment: (Reply)

• 	Sensors without batteries Guest (Marc) on 05/17/2006 at 12:00 AM
  Posts: 1	Josh does not distinguish between inductive coupling (near field technology) and capacitive coupling (far field technology).  These two modes of coupling energy into an RFID tag or a sensing device operate at different distances.  Inductive coupling is more efficient, and one would think that this would be the mode to use to power up "power hungry" microcontrollers. Rate this comment: (Reply)

  • 	Inductive vs. Capacitive coupling Guest (James) on 05/19/2006 at 12:00 AM
    Posts: 1	Unfortunately, you want RANGE for these applications. This implies capacitive coupling. It makes no sense if you have to be very close to a reader. You might as well have a wire and plug into a wall in that case. Rate this comment: (Reply)

    • Power me up Scotty Guest (Cullen) on 06/22/2006 at 12:00 AM

      Posts: 1

      You guys are great!  I'm not an electro wiz like most of you, but the reality of Inductive and Capacitive coupling is something that will be very handy in the near future. Sensing remote information will greatly advance our knowledge of what is going on with the planet and then maybe, given an influx of greater range of thinking ability, we just might save ourselves from... ourselves. Please think on this, design some new products and lets get on this wonderful opportunity of life and invention! Thanks! Rate this comment: (Reply)