I am being told by a RF test lab that I need to provide a sample which has the following modes: BLE "with modulation" BLE "without modulation" ANT+ "with modulation" ANT+ "without modulation"
As far as I understand, the BLE "with modulation" is achieved by using the BLE DTM routines. I see a "special" Nordic specific vendor DTM payload type - CARRIER_TEST - which can be used to test BLE without a modulated signal/"continuous carrier signal".
So, the BLE cases seem to be covered.
For ANT, I am aware of the CW test routines which are present, and these are working.
My main question is - what is the best way to test the ANT+ transmission of a modulated signal?
At the moment the only way I can think of is to use the regular sd_ant_broadcast_message_tx routine. I am concerned though that the "duty cycle" will not be high enough - the test lab has requested that duty cycle be as close to 100% as possible.
I am calling the sd_ant_broadcast_message_tx in an infinite loop, with a payload buffer of 8 bytes. I have a cheap 2.4GHz spectrum analyser (www.oscium.com/.../wipry-combo) and it appears that the radiated power is significantly lower than the equivalent ANT CW test. The significantly lower radiated power is making me think that the duty cycle is not as high as it could be - but I might be mistaken.
EDIT - I thought that I was observing a signal from the usage of sd_ant_broadcast_message_tx, however it was from another transmitter in the room. No matter what I try, I can't seem to see a signal on the analyser when using the sd_ant_broadcast_message_tx approach.
Any help will be greatly appreciated!
-Chris