1.5 Antenna Guidelines

To achieve the best RF performance, follow the antenna recommendations as listed:

• Choose an antenna that covers the frequency band between 2.4 GHz to 2.5 GHz.
• Ensure that the antenna connected to the PCB pad is properly designed for 50Ω impedance. The antenna vendor must specify the pad dimensions, the spacing from the pad to the ground reference plane and the spacing from the edges of the pad to the ground fill on the same layer as the pad. The ground reference plane for the 50Ω trace going from the antenna pad to IS1870/IS1871 is probably on a different layer than the ground reference for the antenna pad. Ensure that the pad design contains a proper transition from the pad to the 50Ω trace.
• Place the antenna-matching components as close to the antenna pad as possible. The antenna does not properly match if the matching components are far away from the antenna.