I want to buy a digital anti-aliasing filter (preferably from NI) with following specifications:
1) Digitally controlled cutoff frequency from 10kHz to 100kHz.
2) Real-time response.
3) 100dB reduction in gain in a span of 2.5 times cutoff frequency.
I want to use it for the following application:
I am using data acquisition board (USB 6356) at 500K Samples per seconds and I want to analyze frequencies in between 100Hz to 50KHz. I want to remove all higher frequency very efficiently using anti-aliasing filter before data acquisition step. This is important because I want to profile underwater noise. Therefore, I want to remove signals above 100Khz completely. I also have USB 6281 board with 40KHz filter but this filter is not sufficient as it is allowing signals upto 300KHz.
If you can suggest better external anti-aliasing filter specifications (and product name) than it would be of great help for me.
I am sorry as I asked something not related to NI product.
Thank you.