Method and apparatus for sensing environmental parameters using wireless sensor(s)

A passive radio frequency identification (RFID) sensor, comprising:

• a first inductive loop, wherein the first inductive loop has a first impedance, the first impedance operable to vary in response to an environmental parameter proximate to the first inductive loop;
• a processing module coupled to the first inductive loop, the processing module comprising:
• a tuning module coupled to the first inductive loop, the tuning module operable to:
• vary a first reactive component impedance coupled to the first inductive loop in order to change a system impedance, the system impedance comprising the first inductive loop impedance and the first reactive component's impedance,
• produce a first impedance value representative of the first reactive component's impedance;
• a memory module operable to store the first impedance value representative of the reactive component's impedance;
• and
• a wireless communication module coupled to the processing module, the wireless communication operable to communicate with an RFID reader, the wireless communication module operable to exchange the first impedance value with the RFID reader.

A passive radio frequency identification (RFID) sensor, comprising:

• a first inductive loop, wherein the first inductive loop has a first impedance, the first impedance operable to vary in response to environmental parameter(s) proximate to the first inductive loop;
• a second inductive loop, wherein the second inductive loop has a second impedance, the second impedance operable to vary in response to environmental parameter(s) proximate to the second inductive loop;
• a processing module coupled to the first inductive loop and the second inductive loop, the processing module comprising:
• a tuning module coupled to the first inductive loop and the second inductive loop, the tuning module operable to:
• vary a reactive component impedance coupled to each inductive loop in order to change a system impedance, the system impedance comprising each inductive loop impedance and the reactive component's impedance,
• produce an impedance value representative of each reactive component's impedance;
• a memory module operable to store the impedance value representative of the reactive component's impedance;
• and
• a wireless communication module coupled to the processing module, the wireless communication operable to communicate with an RFID reader, the wireless communication module operable to exchange the impedance values with the RFID reader.