Hello,
We use nRF52840(0dBm)+nRF21540(Dec6).
In the case of using nRF52840+nRF21540, tx spurious emissions occurs severely in the nRF21540 output.
FEM(nRF21540) output waveform shows high spurious emission near the channel edge.
Comparison at the same ~8dBm Tx power output, shows lower spurious emissions at BLE outputs without FEM.
It can be also easily seen the Conducted Tx output measurement waveform below.
(1) nRF52840(0dBm)+FEM(Dec6) = Total ~+8dBm
(2) nRF52840(8dBm) = Total ~+8dBm
Due to the Tx spurious emission issue, we are currently failing the Radiated Spurious Emissions item in FCC certification in the test.
Please support us solve this problem.
Thank you.
