Signal Detection Method for Interference From Inverter Microwave Ovens in WLAN Systems

Inverter microwave ovens (inv. MWOs) are day-today appliances that can severely interfere with 2.4 GHz wireless LAN (WLAN) devices. However, interference is avoidable by using a signal detection method that recognizes MWO signals. In our previous work, we have proposed a specialized detection method that recognizes characteristic power levels of leakage signals from inv. MWOs, which drastically vary depending on the switching of the inverter. Using experimental MWO data obtained in a shielded room, we also demonstrated that the proposed method correctly detects inv. MWO signals with robustness against different products, different receiving environments, and the presence of other signals. In this paper, we begin with a discussion of the influence of MWO interference, and then review process and evaluation of the proposed method, along with new additional analysis. By simplifying the process, we also provide a test chip implementation for method realization and real-time signal detection to enhance the reliability of WLAN systems. Finally, we use the test chip to show that it is also possible to detect jammer signals.