RE: Extracting I/Q samples from BLE signals

Jay Tyzzer — Wed, 10 Apr 2019 18:32:17 GMT

Hi Flo,

Check out the new nRF52811. It has I/Q functionality.

Br,

Jay

RE: Extracting I/Q samples from BLE signals

AmbystomaLabs — Mon, 03 Dec 2018 19:00:33 GMT

Functionally there is no I/Q associated with BLE signals unless you want to consider it some variant of a hilbert transform with upper and lower sidebands. BLE uses FSK, and likely Nordic just write registers on their synth to affect this, though it is possible for them to use an I/Q baseband also but it just wouldn't be as easy.

None of the nRF devices offer any baseband, nor IF output.

If you just want to work with baseband signals, go to the Analog Devices site. They offer a bunch of development boards with direct conversion receivers some even have on board A/D conversion.

And, if you really want to learn about I/Q you should work with WiFi signals. Depending on the standard you can choose from OFDM with pi/4 to 256QAM subcarriers and the older standards b/g have QPSK, BPSK with direct sequence spread. Some older Atheros reference designs have I/Q available on the board since they used to implement it as a two chip solution. You can probably pick up a cheap old router and rip it apart.