Multiplexing NFC Antennas : An evaluation of the technique and its limitations

Sammanfattning: Introduction This study aims to investigate the possibility of driving multiple NFC antennas with a single NFC-controller by using a multiplexer. An artifact was developed and experiments were conducted in order to evaluate the design choice and in addition, to observe the impact of a multiplexer in an NFC system with respect to the number of successful tag detections, bit error rate (BER), the utilization of automatic antenna tuning (AAT) and the physical distance to the NFC tag. Data collected from the experiments was analyzed, and the results were discussed. The purpose of the thesis was concretized by formulating three research questions: [RQ1] How can the design proposed in the problem statement be implemented? [RQ2] How does the multiplexer impact the system’s ability to detect an NFC tag and read its contents at different distances? [RQ3] To which degree does the AAT-technology compensate for the issues caused by the multiplexer? Method This research has been conducted according to the design science research (DSR) methodology. DSR is a well-established methodology and suits the nature of this research, therefore it is used to answer the research questions. Findings The thesis demonstrates a viable solution using a multiplexer in NFC systems, with reduced detection distance as a factor to consider. The impact of AAT remains inconclusive, requiring further research. Implications This study shows that using a multiplexer in NFC systems can save costs and space, leading to more affordable and compact devices. It enables scalable, advanced NFC devices for diverse applications, encouraging wider adoption. However, developers must consider the impact of a multiplexer on detection distance when designing NFC-based applications Limitations This study has certain limitations. It focuses on a particular multiplexer and NFC antenna type, and specific testing conditions. It does not delve into the potential profitability, diverse applications, security or encryption concerns, compatibility with other devices, compliance with regulations, or hands-on verification of part connectivity.