Can the NRF52 output an unmodulated continuous tone at a specific channel?

[ray]

Hi all,

I'm a grad student trying to innovate on the BLE concept. I require a continuous signal as a source: preferably unmodulated, but a long duty cycle could also work. Would the NRF52 (or any other Nordic bluetooth device) be able to accomplish this?

Thank you, Ray

[Øyvind Karlsen]

Hi,

Yes you can do this. I recommend using either the radio test example or alternately direct test mode. Both implement this already and can be found in the SDK under nRF5_SDK_11.0.0_89a8197\examples\peripheral\radio_test and nRF5_SDK_11.0.0_89a8197\examples\dtm\direct_test_mode.

Best regards,

Øyvind

[Øyvind Karlsen]

Hi,

This sounds extremely interesting, really cool thesis! I have found a paper that has done what you are trying to do using a nRF51822 chip that I think you will find very helpful.

Ensworth, Joshua F., and Matthew S. Reynolds. "Every smart phone is a backscatter reader: Modulated backscatter compatibility with bluetooth 4.0 low energy (ble) devices." 2015 IEEE International Conference on RFID (RFID). IEEE, 2015.

If I'm understanding you correctly that means that you are trying to compress the method described in this paper into two nodes?

For a functional test I think all three nodes described in this text can be realized partly by a nRF5 chip. CW output from the chip should be faily straight forward. You ccould also use it to generate the output frequency for the backscatterer. Finally it is already proven as a competent BLE receviver.