Electronic transponder tuning procedure

A method of communicating between an interrogator unit having a first resonant circuit and a responder unit having a second resonant circuit, said method comprising the steps of:

• a) storing energy in a responder unit energy accumulator in a contactless fashion by RF energy transmitted from said interrogator unit to said responder unit;
• b) exciting within said responder unit an RF carrier wave;
• c) transmitting said RF carrier wave in a first response from said responder unit to said interrogator unit;
• d) measuring within said interrogator unit the signal strength of said first response;
• e) transmitting at least one RF programming sequence from said interrogator unit to said responder unit;
• f) receiving at said responder unit a first set of data transmitted by said RF programming sequence from said interrogator unit;
• and
• g) adjusting the resonant frequency of said responder unit resonant circuit responsive to said first set of data.

A method of communicating between an interrogator unit having a first resonant circuit and a responder unit having a second resonant circuit, said method comprising the steps of:

• a) storing energy in a responder unit energy accumulator in a contactless fashion by RF energy transmitted from said interrogator unit to said responder unit;
• b) exciting within said responder unit an RF carrier wave;
• c) transmitting said RF carrier wave in a first response from said responder unit to said interrogator unit;
• d) measuring within said interrogator unit the signal strength of said first response;
• e) storing said measurement of said first response signal strength;
• f) transmitting a RF programming sequence from said interrogator unit to said responder unit;
• g) receiving at said responder unit a first set of data transmitted by said RF programming sequence from said interrogator unit;
• h) adjusting the resonant frequency of said responder unit resonant circuit responsive to said first set of data;
• i) transmitting said RF carrier wave in a second response from said responder unit to said interrogator unit;
• j) measuring within said interrogator unit the signal strength of said second response;
• and
• k) comparing said stored first response measurement to said second response measurement.

Transponder arrangement comprising:

• a) an interrogator unit which transmits at least one RF programming sequence containing tuning data followed by at least one RF interrogation pulse, said interrogator unit comprising
• i) a transmitter which transmits said RF interrogation pulse and said RF programming sequence,
• ii) a receiver for receiving a wireless response from a responder unit,
• iii) a detection circuit for detecting the strength of a carrier wave generated by said responder unit, and
• iv) a control circuit for analyzing the detected strength of said carrier wave and for determining if a new set of tuning data for another RF programming sequence needs to be computed;
• and
• b) a responder unit which upon receipt of said RF interrogation pulse transmits read data stored therein back to the interrogator unit in the form of said wireless response, said responder unit comprising
• i) a responder unit reception circuit for receiving said tuning data transmitted by said RF programming sequence from said interrogator unit,
• ii) a memory suitable for having memory data therein modified by said tuning data received by said reception circuit,
• iii) a responder unit energy accumulator which stores energy contained in the RF interrogation pulse,
• iv) a responder unit RF carrier wave generator having a resonant frequency, and
• v) a tuning circuit which modifies the resonant frequency of said RF carrier wave generator in accordance with said memory data.