RFID

Read range

However, read range is both a function of the reader and the tag itself.
Improvements in technology may increase read ranges for tags.
Having readers very close to the tags makes short range tags readable.
Generally, the read range of a tag is limited to the distance from the reader over which the tag can draw enough energy from the reader field to power the tag.
Tags may be read at longer ranges than they are designed for by increasing reader power.
The limit on read distance then becomes the signal-to-noise ratio of the signal reflected from the tag back to the reader.

Researchers at two security conferences have demonstrated that passive Ultra-HighFID tags, not of the HighFID type used in US passports, normally read at ranges of up to 30 feet, can be read at ranges of 50 to 69 feet using suitable equipment.



IBM Verichip

Technical characteristics of RFID chips:


ACTIVE
-Longer read range
(1-300 ft.) - do 100 metara
-Tags can be read-write with onboard memory
-Can connect to sensors (i.e. tag tamper, temperature, on/off)
-Battery-dependent operational life(5month-6 years)


PASSIVE(koriste se za implantate,bez izvora napajanja)

-Shorter read ranges
(1-10 ft.) -do 3 metra
-Lighter tags; can be very small
-Requires a higher powered reader ($1000-3000); portable readers require frequent recharging
-Tag is entirely inactive unless within proximity to reader (and energy source)
-Most read-only


Tako da se moze videti da su tvrdnje o maloj udaljenosti iscitavanja signala totalno neistinite. Kljucna osobina je da se domet tag-a moze povecati(i regulisati) nezavisno od tipa ugradjenog cipa vec zavisi i od prijemnog dela.
Postojece tehnologije daju itekako mogucnosti za zloupotrebu.