A signal is 90deg-phase-shifted on LABVIEW FPGA

[ThanhDong]

Hi wWiebe@CARYA,

1. I make some programs using FFT and inverse FFT function to create a 90deg-phase-shifted signal from an original signal in normal LABVIEW. They are attached below (Hilbert-NTD & Hilbert1-NTD).

Can you help me to make them in FPGA LabVIEW?

2. I also consider FIR filter for Hilbert transform in FPGA LabVIEW. I am following the "Polyphase Interpolation FIR Filter on FPGA with DFD and Coregen". They showed at the link https://forums.ni.com/t5/Example-Program-Drafts/Polyphase-Interpolation-FIR-Filter-on-FPGA-with-DFD-...

I used an example: FFT project with FPGA Target (RIO, cRIO-9075, simulation) in the "Find Examples" of LABVIEW help for SIMULATION (2.HlBERT-FPGA.zip).

2. Hilbert-FPGA.zip

However, I can not know how to transfer the output of Hilbert transform (the 90deg-phase shifted signal) to HOST. So I can not compare the phase of the 90deg-phase shifted signal with that of the original output (output 0).

Even I also do not know that the Hilbert transform using the FIR filter is true or not.

Please help me to correct this program.

Thank so much.

Dong

[wiebe@CARYA]

Someone else has to pinch in. I do not have an FPGA at the moment.

As for transferring the data to the host, an FPGA-host FIFO might work.

[wiebe@CARYA]

Apparently, continued here:

https://forums.ni.com/t5/LabVIEW/Hilbert-transform-90-degree-phase-shift-on-FPGA-using-FIR-filter/m-...

Case closed?

[ThanhDong]

For using IR filter to generate Hilbert transform in FPGA LabVIEW, I am not sure the FIR algorithm is true or not (https://forums.ni.com/t5/Example-Program-Drafts/Polyphase-Interpolation-FIR-Filter-on-FPGA-with-DFD-...). Can it be made in normal LABVIEW environment?

I am sorry, I still open two cases.

Thanks for your advice.

Dong

[wiebe@CARYA]

I think the link you're referring to is only remotely related to your problem. The only think in common is he uses a FIR filter. The PDF he's referring to gives more information about the configuration of the FIR filter.

[James_McN · Accepted solution]

Also have a look at the digital filter design toolkit if you have it as part of your software package. It allows for the interactive design of filters and then FPGA IP generation. It's not the most user-friendly tool but I've used it when I needed a linear phase response filter.

[ThanhDong]

Dear James_McN ,

Could you please describe in more details? Could you please give an example? I am a beginner for LABVIEW and FPGA LABVIEW. 

Thank you so much.

Dong

[ThanhDong]

Dear wiebe@CARYA ,

I made a program in normal LABVIEW below. Could you please consider it and give me your advice how to shift the phase of an input signal to 90 deg.

My program is based on https://forums.ni.com/t5/Example-Program-Drafts/Polyphase-Interpolation-FIR-Filter-on-FPGA-with-DFD-...

Thanks,

Dong