A mat based antenna and heater system for use in detecting transponder tagged objects which are used in performing medical procedures, the mat based antenna and heater system comprising: a first sheet of an electrically insulative material that is sized to support at least a portion of a patient, the first sheet having an upper face and a lower face opposed to the upper face; a plurality of antennas positioned successively along at least a portion of a length of the first sheet, the antennas sized and dimensioned to oscillate in at least one of an RF or microwave frequency range in response to a signal; a first layer of silicon carried by the upper face of the first sheet; a second layer of silicon carried by the lower second face of the first sheet; a gel layer positioned relatively above the first layer of silicon with respect to the first sheet; a foam layer spaced relatively above the gel layer with respect to the first sheet; characterized by at least one electrical resistance heater element positioned along at least a portion of length of the foam layer, the at least one electrical resistance heater element sized and dimensioned to dissipate heat in response to a current passing therethrough without oscillation in at least one of the RF or microwave frequency range, wherein the antennas are formed of a first electrically conductive material having a first resistivity, the at least one electrical resistance heater element is formed of a second electrically conductive material having a second resistivity, the second resistivity substantially higher than the first resistivity, and wherein the second resistivity is at least approximately 49 micro-ohms•cm at 20°C. a first sheet of an electrically insulative material that is sized to support at least a portion of a patient, the first sheet having an upper face and a lower face opposed to the upper face; a plurality of antennas positioned successively along at least a portion of a length of the first sheet, the antennas sized and dimensioned to oscillate in at least one of an RF or microwave frequency range in response to a signal; a first layer of silicon carried by the upper face of the first sheet; a second layer of silicon carried by the lower second face of the first sheet; a gel layer positioned relatively above the first layer of silicon with respect to the first sheet; a foam layer spaced relatively above the gel layer with respect to the first sheet; characterized by at least one electrical resistance heater element positioned along at least a portion of length of the foam layer, the at least one electrical resistance heater element sized and dimensioned to dissipate heat in response to a current passing therethrough without oscillation in at least one of the RF or microwave frequency range, wherein the antennas are formed of a first electrically conductive material having a first resistivity, the at least one electrical resistance heater element is formed of a second electrically conductive material having a second resistivity, the second resistivity substantially higher than the first resistivity, and wherein the second resistivity is at least approximately 49 micro-ohms•cm at 20°C.