Electronics

Current Thinking
What we need is a barcode that can be read from some distance away even if
obscured, is difficult to damage and small enough to put on or in almost anything.

Welcome to the world of RFID or Radio Frequency IDentification.

RFID is not new, in fact it's been around since the early 80's but like so many
potentially disruptive technologies it has been developing quietly in the background
and has already been in specialist use for some years. What is new is that technology
has advanced to the point that tiny robust RFID chips are starting to be
manufactured very cheaply. They are rapidly approaching the point were their tiny
size and cheapness means they can literally be built into products from clothing to
computers.

In simple terms, current RFID chips come in two flavours, passive and active.

Passive chips as the name suggests sit passively waiting to be interrogated before
responding and transmitting their data. They have no built in power and rely on the
reading device transmitting a signal, which is then also used to power the chip. The
range of these devices is limited to a few meters depending on various factors and
conditions but can be made extremely small. Devices as small as a grain of pepper
have already been demonstrated.

Active devices are larger (but getting smaller) and contain their own power supply.
They can transmit over a larger range and can also transit continuously or wait until
scanned before answering.