On 11/11/19 10:46 AM, Snehasish Kar wrote: > I tuned the usrp to 947.4MHz with sample rate of 25msps. And then using the > example in the link I tried shifting the frequency to the centre, so that I > can apply a low pass filter and perform resampling on it.
So you're not using gnuradio to shift the signal? It's trivial to do in gnuradio - assumiing your capture has a signal to shift. If you are using gnuradio, then you should post the GRC file. -- Cinaed > > BR > Snehasish > > Sent from my iPad > >> On 11-Nov-2019, at 10:02 PM, Müller, Marcus (CEL) <[email protected]> wrote: >> >> Hi Snehashish, >> >> it's not really clear what you did exactly. How did you do the >> shifting? Did you already take the mixing (probably by 947.4 MHz) done >> by your SDR freontend into account? >> (Also, frequencies and bandwidths have units!) >> >> Best regards, >> Marcus >> >>> On Mon, 2019-11-11 at 14:55 +0000, Snehasish Kar wrote: >>> Hello >>> >>> I tried capturing GSM 900 band at a sample rate of 25e6 centered at 947.4e6 >>> and stored in a file. Then on the captured data I tried shifting 935.2e6 to >>> the center and perform a low pass filter samples out followed by a >>> re-sampler to get 200e3 samples out. But I think the spectrum shifting is >>> not wroking as it should be I am following the following link for spectrum >>> shifting https://dsp.stackexchange.com/a/1993. I am using twinrx with 10gig >>> sfp, UHD_3.13.1.0-0-unknown, ubuntu 16.04 and liquid dsp for signal >>> processing. >>> fft - How to shift the frequency spectrum? - Signal Processing Stack >>> Exchange >>> Stack Exchange network consists of 175 Q&A communities including Stack >>> Overflow, the largest, most trusted online community for developers to >>> learn, share their knowledge, and build their careers.. Visit Stack Exchange >>> dsp.stackexchange.com >>> Please let me know, where I might be going wrong. >>> >>> BR >>> Snehasish >>>
