bbConfigureIQ maximum filter bandwidth?

For the bbConfigureIQ function, how is the Maximum Bandwidth column on page 22 of the BB60 API manual calculated? Are these approximated? Some are exactly 0.8 * SampleRate, others are a bit more. I realize they’re maximums, and I can specify narrower filtering…

I’m just trying to decide if I should just use that 80% across the board as a max bandwidth, or populate a table using a 14×2 array and choose a particular decimation/MaxBW pair…

jgauthier,

80% is a good number to use across the board. I will say, there is a trick you can use to ensure you are always getting the maximum available bandwidth. If you simply set the bandwidth equal to the sample rate (100%), then after you configure the receiver you can call the bbQueryStreamInfo function, and it will report the bandwidth that was actually used by the API. It will internally clamp to the upper bound for each given decimation.

The maximum bandwidth for any given decimation was calculated by looking at the decimation filters available at each decimation stage and making a decision about what cutoff frequency is going to give us the performance we need at that given rate.

Regards,
Andrew

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