RE: Spurious Emission when the payload model is set to PRBS9

Andreas — Thu, 11 Apr 2019 08:56:46 GMT

Hi,

These are spurs from the radio PLL calibrating before transmitting each packet. It is completely normal and not a problem. When you transmit a constant carrier, the PLL is locked and does not calibrate like this.

I am noticing your output power though, quite low, are you measuring conducted? Your PCB design does not look optimal, I would expect quite poor performance like this. Note that even if you have ~-10 dBm output power with 0dBm setting now, you might have to tweak the matching network to bring harmonics down within legal levels, and as such you might have to reduce output power even more. We recommend replicating the reference layout exactly to avoid this.

Best regards,

Andreas