Empirical Study of Microwave Oven Electromagnetic Leakage and its Impact on WLAN Signal Quality

Microwave ovens operate in the 2.4 GHz frequency band, overlapping with the most widely used wireless local area network (WLAN) standard. While they are designed with shielding to minimise leakage, deterioration over time can cause electromagnetic interference (EMI). This paper investigates the effect of microwave oven operation on WLAN signal strength and transmission rate through controlled measurements in real environments. The experimental results show that WLAN performance degrades significantly when in proximity to an ageing oven (used for 17 years), particularly when approaching from specific angles (e.g., 45 degrees incidence) where leakage is stronger. Analysis indicates that interference is caused by wideband noise from magnetron radiation leakage, with directionality effects, polarisation matching, and multipath propagation contributing to the observed results. Possible mitigation measures, including shielding enhancement and frequency planning, are discussed.