VLF/LF radio receiver implemented in the STM32F746-Nucleo board
This project was initiated by Alberto di Bene, I2PHD, see www.weaksignals.com ARM-radio section for more details including the paper describing the implementation theory. The first version written by Alberto ran on the STM32F429-Discovery board.
Simon Kennedy, G0FCU, subsequently took the original code and converted to work on the faster STM32F746-Nucleo board, see www.g0fcu.com for blog posts related to this implementation. The code in this repository works on the STM32F746-Nucleo board.
This project implement a SDR (Software Defined Radio) using the STM32F746-Nucleo board, with a minimal amount of external hardware, using all the facilities offered both from the various devices of the chip itself and the middleware support (HAL, CMSIS, STemWin, etc.) provided by ST.
This SDR is of the direct RF sampling variety, where the RF is immediately sampled by an ADC, then processed in numerical form with various DSP algorithms, all implemented taking advantage of the floating point core of the STM32F746 chip and the CMSIS library, and finally sent to the on-chip DAC to be transformed again in analog format, for reproduction by a speaker after being passed through a reconstruction filter.
The src and include folders are self-explanatory. The two 'stm32f7xx_hal' prefixed files are required to overwrite the same files provided by ST in the HAL firmware library v1.3.0
HAL firmware library v1.3.0 is the only version guaranteed to work with this software. In later versions (and certainly in v1.5.1) ST have changed code so it is not backwards compatible.
Please note that the spectogram code is currently experimental. I have added the option to turn it off as the screen refresh causes some interferance.
ARM_Radio is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
ARM_Radio is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.