Remote passive identification system

A system for passively identifying remote objects, comprising

• (a) power transmitter means for transmitting a plurality of radio frequency burst signals at a given frequency;
• (b) passive transponder means associated with the object to be identified, said transponder means producing a plurality of uniquely coded identification signals at said given frequency in response to said burst signals;
• (c) receiver means for receiving said uniquely coded identification signals from said transponder means to identify the object;
• and
• (d) time division multiplexing means for alternately operating said transmitter and receiver means, whereby when the object is to be identified, said transmitter means transmits said burst signals for a limited period of time, thereby activating said transponder means to produce said uniquely coded identification signals, said time division multiplexing means operable to switch off said transmitter means following transmission and to switch on said receiver means to receive said uniquely coded identification signals from said transponder for identifying the object.