Hello EJ Any update on this?
Regards Snehasish Get Outlook for iOS<https://aka.ms/o0ukef> ________________________________ From: Snehasish Kar <snehasish....@live.com> Sent: Friday, April 24, 2020 6:01:27 PM To: EJ Kreinar <ejkrei...@gmail.com> Cc: Jonathon Pendlum <jonathon.pend...@ettus.com>; usrp-users@lists.ettus.com <usrp-users@lists.ettus.com> Subject: Re: [USRP-users] Fractional downsampling in rfnoc Hello EJ I tried using your channelizer. Its really a helpful module. The challenge I faced when i tried using it with a input sample rate of 25msps and tried dividing it into 16 channels. I should have returned 625kspsx2 sample rate each channel. But you can see the snaphshots, if a tune into 955.4MHz and try to get a channel on index 0 ie the center freq, it works well and I am able to decode GSM Burst from it. But if I try to add index 2(which is 955.8MHz), the amplitude in the spectrum falls and also I am not able to decode any GSM burst. The same happens when i tune 955.8MHz and try to get index 14(ie 955.4MHz), I don't see the spectrum, the same happens for 128 and 256 channel (input sample rate 50msps). Can you please let me know if I am going wrong somewhere. I have attached the snapshots and flow graph for your reference. My uhd version is UHD_3.14.0.0-0-unknown. Regards Snehasish ________________________________ From: EJ Kreinar <ejkrei...@gmail.com> Sent: Friday, April 24, 2020 4:22 PM To: Snehasish Kar <snehasish....@live.com> Cc: Jonathon Pendlum <jonathon.pend...@ettus.com>; USRP-users@lists.ettus.com <usrp-users@lists.ettus.com> Subject: Re: [USRP-users] Fractional downsampling in rfnoc Hi Snehasish, Since you're already working with theseus-cores, I assume you've found the rfnoc polyphase channelizer has channel downselection already integrated into rfnoc and gnuradio (brief write up about it here: https://www.theseus-cores.com/2019/12/17/rfnoc-deinterleaving-polyphase-channelizer/). I believe this worked with UHD-3.14 when I tested last December. Wondering if this works for you or if there's other updates you might need? EJ On Fri, Apr 24, 2020, 12:56 AM Snehasish Kar via USRP-users <usrp-users@lists.ettus.com<mailto:usrp-users@lists.ettus.com>> wrote: Hello Jonathon I tried building the fractional downsampler again and was successful to build it in this version of UHD: UHD 4.0.0.rfnoc-devel-409-gec9138eb. Also there is a channelizer available at https://github.com/e33b1711/rfnoc-ppchan . But the problem with this channelizer is, it sends almost 25.6msps samples to the host. Also the number of packet it sends, creates a overflow in the host even with 10gig sfp cable. So what I am planning is to make a de-interleaver, which will be responsible for channel down-selection. Please let me know your thoughts on this. Can you please let me know how to set the packet size on any rfnoc block. Regards Snehasish ________________________________ From: Jonathon Pendlum <jonathon.pend...@ettus.com<mailto:jonathon.pend...@ettus.com>> Sent: Sunday, April 19, 2020 8:58 AM To: Snehasish Kar <snehasish....@live.com<mailto:snehasish....@live.com>> Cc: usrp-users@lists.ettus.com<mailto:usrp-users@lists.ettus.com> <usrp-users@lists.ettus.com<mailto:usrp-users@lists.ettus.com>> Subject: Re: [USRP-users] Fractional downsampling in rfnoc Hi Snehasish, I forgot about that error. I actually made an issue about it on their repo: https://github.com/SynchronousLabs/rfnoc-SynchronousLabs/issues/2. Unless they provide an EDIF or their source code, you can only use their code for simulation. Certainly a disappointing oversight on their part. Jonathon On Sat, Apr 18, 2020 at 6:21 PM Snehasish Kar <snehasish....@live.com<mailto:snehasish....@live.com>> wrote: Hello Jonathon Tried building the fractional downsampler from synchronous labs and have encountered the following error: source file was generated for simulation and is not permitted as input to synthesis [/home/snehasish/rfnoc-SynchronousLabs/rfnoc/fpga-src/fract_dec_filter.vhd:241995] Can you please help me with it. Regards Snehasish ________________________________ From: Jonathon Pendlum <jonathon.pend...@ettus.com<mailto:jonathon.pend...@ettus.com>> Sent: Friday, April 17, 2020 9:22 PM To: Snehasish Kar <snehasish....@live.com<mailto:snehasish....@live.com>> Cc: usrp-users@lists.ettus.com<mailto:usrp-users@lists.ettus.com> <usrp-users@lists.ettus.com<mailto:usrp-users@lists.ettus.com>> Subject: Re: [USRP-users] Fractional downsampling in rfnoc Hello Snehasish, Unfortunately, the standard library of blocks does not have a Fractional Decimator. Your best bet is to try to use the one made by Synchronous Labs a few years ago. Their code is on github here: https://github.com/SynchronousLabs/rfnoc-SynchronousLabs. Since it was built, RFNoC has had some changes that will need to be fixed, but I think this is your only option versus writing one from scratch. Jonathon On Thu, Apr 16, 2020 at 6:35 PM Snehasish Kar via USRP-users <usrp-users@lists.ettus.com<mailto:usrp-users@lists.ettus.com>> wrote: Hello I am trying to use the RFNOC based M/2 channelizer from https://github.com/theseus-cores/theseus-cores/releases/tag/v1.1.0 . I am trying to divide 25 MHz spectrum into 124 subchannels each of bandwidth 200KHz. I am capturing the signal at 200msps and I need to decimate it to 25.6msps(25MHz/128 channels). Please help me in understanding how this can be achieved using RFNoC, is there’s any block already defined for fractional downsampling. Thanks & Regards Snehasish Get Outlook for iOS<https://aka.ms/o0ukef> _______________________________________________ USRP-users mailing list USRP-users@lists.ettus.com<mailto:USRP-users@lists.ettus.com> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com _______________________________________________ USRP-users mailing list USRP-users@lists.ettus.com<mailto:USRP-users@lists.ettus.com> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
_______________________________________________ USRP-users mailing list USRP-users@lists.ettus.com http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
