How to modify the input ports of the CCSDS LDPC decoder and reduce its BRAM resource consumption

The official website states that this block supports scalar inputs and vector inputs of size 8, but in the Simulink example, I noticed that the input port is ufix4, and I couldn’t find any configuration options. How should I modify this? Additionally, I want to reduce BRAM resource consumption. Are there any parameters related to parallelism that can be configured?

Answer 1

[Kranti Balaga]

Hi,

In CCSDS LDPC decoder, you can configure the input port width by simply change the data type of the "decSampleIn"

in the below example:

Decode and Recover Message Using CCSDS LDPC Decoder - MATLAB & Simulink

All the configurations are dynamically changed from the input port such as Code rate index and Block length index for AR4JA configuration.

The only configuration options for compile time is, LDPC configuration between, (8160,7136) LDPC (default) | AR4JA LDPC.

Since the code rate and block lenghts are changed dynamically, we dont have an option to reduce the BRAM count. Also, dont have an option to configure the parallelism parameter.

Let me know your requirements, and settings to understand your usecase.

Thanks,

Kranti

[玉杰]

Thanks a ton for breaking that down! Switching to a parallel input setup makes total sense for boosting decoding speed. That's actually a really useful tweak I hadn't thought about before.I'm definitely gonna try some other tricks too to save BRAM space, like we chatted about.