Direct Antenna Modulation scheme for enhanced capacity performance of near-field communication link

Abstract

Shannon theorem suggests that power coupled through and bandwidth of an inductively coupled near field communication (NFC) link must be traded off for optimal capacity. Direct Antenna Modulation (DAM) is a possible scheme to break this dilemma. With DAM technology utilized in NFC link, the power and bandwidth product limit in a high Q system can be circumvented because of non-linear/time varying operation. In this paper, a NFC link, consisting of identical transmitter and receiver coils of 5 cm radius and 24 turns with a Q value of 35, operating at 283 kHz is used. DAM is implemented on transmitter side and improvement in capacity is experimentally demonstrated for low loaded Q receiver.