Patent ID: 8742931

Claim:
An electronic seal including: a plug including a hollow body, an insertion end formed at an end of the hollow body, and a stop end formed at an opposite end of the hollow body, wherein a cross-sectional area of the stop end of the plug is larger than a cross-sectional area of the hollow body; a socket including a hollow body and a locking apparatus, wherein the hollow body of the socket includes an internal space defined therein and an opening through which the insertion end of the plug is insertable in the internal space of the hollow body of the socket, wherein the locking apparatus is located in the internal space of the hollow body of the socket corresponding to the opening of the hollow body of the socket for receiving the insertion end of the plug to thereby lock the plug to the socket, a radio frequency identification apparatus including at least two radio frequency identification units, each for providing a specific code for identification and arranged within the hollow body of the plug such that at least one of the radio frequency identification units is arranged so as to also be encased by the socket when the plug is fully inserted in the socket; an antenna assembly arranged in the socket and electrically connected to the radio frequency identification units when the plug is inserted in and locked to the socket, wherein the antenna assembly is used to receive an electromagnetic signal for identification to excite the radio frequency identification units to transmit the specific codes through the antenna assembly, wherein when the plug is cut, the at least one radio frequency identification unit is left unbroken in the socket together with the insertion end of the plug and can transmit the specific code through the antenna assembly; and an impedance matching circuit provided between the radio frequency identification units and the antenna assembly for adjusting the impedance matching of the radio frequency identification units to the antenna assembly, thus adjusting excitation powers and feedback powers of the specific codes transmitted from the radio frequency identification units through the antenna assembly.