View source for Audio FMCW

== Introduction ==

To demonstrate RADAR concepts without RF/an SDR, it's possible to use a sound card to generate a FMCW chirp and receive any returns. The caveat is that without special processing, it is usually not possible to synchronise the TX and RX streams in consumer audio cards.

This can be demonstrated in GNU Radio with a simple [https://github.com/balint256/gr-baz/blob/master/examples/Audio%20FMCW.grc flow graph] (and some additional visualisation blocks).

== Video ==

* [https://youtu.be/psuEzxFJnZY?t=2126 DEF CON 25 Wireless Village 2017]
* [https://youtu.be/yZ5G0nYSM98?t=4138 DEF CON 24 Wireless Village 2016]