1.4 Interference Guidelines

The interference affects the RF receiver performance on the board, radiating noise into the antenna or coupling into the RF traces going to input LNA. Following the interference recommendations as listed is mandatory:

• Ensure that there is no noise circuit placed anywhere near the antenna or the RF traces. Shield all the noise-generating circuits so that they do not radiate noise that the antenna picks up.
• Ensure that no traces route underneath the RF portion of the IS1870/IS1871 input.
• Ensure that no traces route underneath the RF traces from the antenna to the IS1870/IS1871. This applies to all layers.
• Even if there is a ground plane on a layer between the RF route and another signal, the ground return current flows on the ground plane and couples into the RF traces.