Re: Round trip time calculation - simulation

[Johannes Demel]

Hi Jiya,

It seems like you want to measure the DSP latency in a flowgraph without 
hardware.

For better readability, I suggest to use a service that lets you upload 
screenshots in higher resolution and you just share the link.

In said screenshot, I suggest to mark your start end endpoint for your 
measurement. Thus, we all know exactly what you want to do.

The "Throttle" block will have an influence on your measurement even if 
it is before your measurement starting point because it influences GR 
scheduler behavior.

The timestamp and latency measurement approach seems sensible. I used 
the same approach for such investigations.

How do you want to track the timing for 1 sample?
Especially FEC works on blocks. A lot of blocks do. Not just in GR but 
just in principle.
I assume that you want to measure the time it takes for a frame of 
specific size to be processed.

Since I don't know which GR version you use, you might want to double 
check if all the rate changing blocks place the tags on the correct 
sample in the output.

These are a few thoughts that came to mind when I looked at your flowgraph.

Cheers
Johannes

On 30.08.23 11:40, Jiya Johnson wrote:
> Hello, community. I have attempted to create a system that uses
> 1. A random source as input
> 2. A time stamper.These inputs are provided to the encoder, which 
> performs the modulation and demodulation
> 3.I want to track back the timing for 1 sample (latency) after using the 
> decoder; can somebody tell me whether my flowgraph is correct?
> Screenshot from 2023-08-26 11-24-39.png

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