Casing and hand effect on PCB antenna in 2.4 GHz wireless mouse: A measurement based characterization

摘要

In this paper, the effect of plastic casing and hand, on 2.4 GHz PCB antenna used in wireless mouse is investigated thoroughly from measurement. A systematic observation from measurement reveals two types of shift in the resonance of PCB antenna. The resonance shift caused by plastic casing is referred to as Static Shift, and is relatively easy to correct for. The resonance shift caused by hand is referred to as Dynamic Shift, and is detrimental for the performance of antenna in the final product. However, measurement concludes that, Dynamic Shift is significantly nullified for antenna placed around 4 mm away from edge of casing. This data when used effectively, while PCB floor planning is expected to improve the overall performance of the product, particularly for products used in dynamic environment like wireless mouse, presenter, keyboard.