continued from part II: The passband of CIC filters is not flat. This begs the question of whether this behavior should be corrected. In most cases, the CIC is therefore followed by a so-called CIC compensation filter. Zooming into the filter plot of the sinc4/dec.15 Read More …
Monat: Juni 2021
The DFSDM of the STM32H7 or 128 != 16×8 != 8×16 (Part II)
continued from part I: As explained in part I, the first version of my H7-SDR uses only one CIC filter of the DSFDM for filtering the I-signal and another one for filtering the Q-signal. However, the DSFDM contains 4 filters (see chapter 30 of RM0433 Read More …
The DFSDM of the STM32H7 or 128 != 16×8 != 8×16 (Part I)
My software defined radio for receiving AM transmissions in the 49 m band (see https://dm1cr.de/reception-of-radio-darc-transmission-with-a-microcontroller-only-sdr) looks quite primitive in the first version: It comprises a bandpass filter for anti-aliasing, an STM32H743ZI microcontroller and an audio amplifier with loudspeaker. The ADC inside of the STM32H7 is Read More …
Reception of a Radio-DARC-transmission with a microcontroller-only-SDR
A few moments ago I was able to receive the Radio-DARC-transmission from 11:00 CEST, Sunday, June 13, 2021, with my homebuilt SDR, that just became ready for a first try on the antenna. The received sound was loud and clear. The SDR comprises an anti-aliasing-filter, Read More …
Bandpass sampling and analog bandwidth of the 16-bit ADC peripheral of the STM32H7, Part II
The STM32H7-application sends ADC data to the PC via USART3. Rx and Tx of USART3 are connected to the ST-Link debugger on board of the NUCLEO-STM32H743ZI. The ST-Link driver that gets installed when you install the STM32CubeIDE supplies also a virtual COM port that can Read More …
Bandpass sampling and analog bandwidth of the 16-bit ADC peripheral of the STM32H7, Part I
I have to admit of having had some prejudices about ADCs in microcontrollers.From my experience, they are slow and noisy of no use for really demanding applications.Well, the 16-bit ADC peripheral of the STM32H7 of ST Microelectronics may be a real game-changer. It seems to Read More …