IF to IQ in LV code

[E=McHammered]

I have been given the task to convert IF data to IQ data. I am told the IF will be represented as an array of I16 values. I need to perform a complex multiply and then apply a FIR Low Pass filter. Afterwards, I must decimate and then interleave the I's and Q's. I am having a horrible time with the filtering. My boss is telling I don't need to know the sample rate or frequency of the IF data. I just need to know the frequency to down convert to ( that of the oscillator we are using ) and the rest should fall into place. However, all that is falling is the hair off my head as I pull it out in frustration. I've tried looking at examples online and and in Labview help, but they all require data about the IF that I am not privy to. Any help would be greatly appreciated.

I am not allowed to post code do to the nature of my job.

[Baji]

Where u having the problem?

[JK1]

Its not possible to filter a data without the sampling information.  Oscillator you mentioned is the oscillator of your hardware [that is part of signal conditioning] or related to daq hardware (ie like some sample clock that helps in daq)

just define the oscillator purpose so that we can try to establish a link with IF (if possible 🙂 )

Post back for queries.

[E=McHammered]

The oscillator is part of the hardware for signal conditioning. Where I am up to right now is I am multiplying the IF which will be presented as an array of I16s by a cos and sin signal which are set to the frequency of the oscillator. This basically gives me my I and Q data, but it is subject to intial carrier frequency of the RF/IF signal. So I'm going to treat the carrier frequency as noise and filter it out with a FIR LPC, and that is my problem. I can not get a FIR LPC that works. Now this is going to be done in post processing so it doesn't have to be the fastest algorithm. But, I am trying to work on my real time processing skills and would like to develope and algorithm that could work on the fly if need be. Any help with FIR LPC would be appreciated. I looked at the examples in LV, but they all seem to require info that I don't need.

[E=McHammered]

Let me rephrase, all the examples on FIR filtering require info that my boss tells me I don't need and therefore I won't be privy to it.