I am observing unexpected behavior for one of our products using QN9083 BLE SoC. When I measure the device receiver sensitivity, I am seeing deltas up to 10dB between consecutive measurements. I am using a CMW100 in advertiser mode to perform measurement and the device is placed in a shielded RF box. Performing consecutive RxS measurements, without opening the box and/or changing device location, the device responds with up to 10dB difference (i.e., -91dBm and -81dBm) which is unexpected and never happened before. The behavior is random. I am looking for possible causes both hardware and software.
Hello,
A variation of up to 10 dB between consecutive sensitivity measurements is not something we would normally expect.
Could you share the software/SDK version currently being used?
Also, can you clarify:
Does this occur on a single device or multiple products?
Have you seen the same behavior across different units?
Can the issue be reproduced on an NXP development board using the same measurement setup?
This information will help determine whether the issue is specific to the hardware, software, or test environment.
Best Regards,
Ricardo
Hello thank you for getting back to me. Here are my answers:
Could you share the software/SDK version currently being used?
5.0 based on 156414 (Controller Subsystem) and 156821 (Host Subsystem)
Does this occur on a single device or multiple products?
Same product. Never had the issue with different products.
Have you seen the same behavior across different units?
Yes but not consistently
Can the issue be reproduced on an NXP development board using the same measurement setup?
I will need a dev board with QN9083 and a FW that will set the chip on advertising
Thank you,
Additional info regarding BLE version:
SDK 2.2.3 BLE 1.5.6 that supports BLE Core 5.0.
I ran measurements using QN9080-DK. Although I do not see 10dB discrepancy there is still 5dB fluctuation (see data below). What could cause this?
Thank you.