Microwave-tolerant RFID tag

An RFID tag comprising:

• an RFID chip;
• a plurality of first conductors spaced apart from one another in a first array with a shape of at least part of an antenna;
• a plurality of second conductors spaced apart from one another in a second array with the shape of the at least part of the antenna;
• an envelope comprising insulative material, the envelope enclosing the RFID chip, the plurality of first conductors and the plurality of second conductors, the envelope comprising:
• a first internal surface, an outer wall of flexible material disposed outside the first internal surface, a communicating channel and a fluid reservoir holding a fluid;
• wherein the outer wall substantially covers the first internal surface and has a second internal surface disposed opposite the first internal surface, such that the first and second internal surfaces bound an antenna chamber;
• the communication channel extends between the fluid reservoir and the antenna chamber for fluid communication therebetween;
• and wherein the plurality of first conductors are fixed on the first internal surface and the plurality of second conductors are fixed on the second internal surface,
• the outer wall is urged inwardly by ambient pressure to press the plurality of second conductors into electrical contact with the plurality of first conductors and thereby form the at least part of the antenna, and
• a pressure of fluid in the antenna chamber tends to displace the outer wall outwardly to thereby separate the plurality of second conductors from the plurality of first conductors.