Re: Controlling flowgraph

[Marcin Puchlik]

Vamshi,

I just gave you an example in the last message. To get more information about the stream tags, please check out the GNU Radio wiki website

https://wiki.gnuradio.org/index.php/Stream_Tags

Marcin 

pon., 6 cze 2022 o 15:46 Vamshi Sainath Gavani <rafale10574@gmail.com> napisał(a):

can you give me an example of what the tags have to be?

also, take a look at how I'm implementing the example you provided in my flowgraph.

On Mon, Jun 6, 2022 at 6:31 PM Marcin Puchlik <m.puchlik@is-wireless.com> wrote:

Hey,

So lets say that your hardware expects you to send samples at 1 MSPS rate (1 million samples per second). Lets also assume that your bursts always have 100k (one hundred thousand) samples. Let's also assume that you want to send you bursts at 1 second period. What you have to do is to add 900k additional null or noise samples after your burst samples to satisfy the hardware. You can do that by using Tagged Stream Mux block where you apply two tagged streams: burst stream (burst samples on the image) and null stream (null samples on the image). Remember that both streams have to be tagged. 

I hope that helped

pon., 6 cze 2022 o 13:50 Vamshi Sainath Gavani <rafale10574@gmail.com> napisał(a):

Hey Marcin,

Can you explain to me in short how to send null samples to the soapy sink or a link maybe? Sorry, I'm new to the GNU environment.

Thanks.

On Mon, Jun 6, 2022 at 2:00 PM Marcin Puchlik <m.puchlik@is-wireless.com> wrote:

Vamshi,

I don't think that HackRF One supports bursty transmission (like USRP UHD does). If you want to achieve a 3 seconds period bursty Tx you have to provide an adequate amount of 'null' samples between the transmission bursts to drive DAC. To verify that information I think you can ask on HackRF mailing list. I think that people there will provide you more reliable info.

Best,

Marcin

pon., 6 cze 2022 o 10:12 Vamshi Sainath Gavani <rafale10574@gmail.com> napisał(a):

So what I'm doing is transmitting with a HackRF One and when I run the flowgraph the transmission starts and frames are sent as bursts and between the bursts, the transmitter stays on and I would like to turn it off at tx_eob and turn on tx at tx_sob

Below is the screenshot of the current flowgraph I'm implementing.

On Mon, Jun 6, 2022 at 1:14 PM Marcin Puchlik <m.puchlik@is-wireless.com> wrote:

Hi Vamshi,

First, what do you mean by turning off/on the transmitter? 

Marcin

pon., 6 cze 2022 o 09:14 Vamshi Sainath Gavani <rafale10574@gmail.com> napisał(a):

Hello Folks,

Here I'm implementing the transmission of LoRa Frames and I want to be able to stop the flowgraph(Stop Transmitting) between frames say the packet is set to transmit every 3s so at tx_eob turn off tx and tx_sob start tx.

Below is my Flow graph code snippet can you let me know how I can turn off/on tx between the frames?

def main(top_block_cls=lora_TX, options=None):
    tb = top_block_cls()

    def sig_handler(sig=None, frame=None):
        tb.stop()
        tb.wait()
        sys.exit(0)

    signal.signal(signal.SIGINT, sig_handler)
    signal.signal(signal.SIGTERM, sig_handler)

    tb.start()
    try:
        input('Press Enter to quit: ')
    except EOFError:
        pass
    tb.stop()
    tb.wait()

if __name__ == '__main__':
    main()

Thanks and Regards,

Sainath Vamshi