In this PDF: https://infocenter.nordicsemi.com/pdf/nwp_037.pdf
On page 28 it says:
Active components on the PCB cause wideband noise coupling to the antennas. Verify that during reception, especially GPS, active components on the PCB do not radiate noise to the GPS antenna. For example, DC converters and LEDs are typical sources of radiating wideband noise.
My question is in regards to LEDs being a wideband noise radiator. Why is the case?
Is wideband noise intrinsic to the generation of light?
Or is it the PWM signal edges?
Or is it noisy power being supplied to the LEDs through long traces that radiate?
Thanks for any clarification... I myself see strange EMI issues sometimes and I'd like to know what you know :)
