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Re: [Discuss-gnuradio] Continous Transmission using GNU RADIO. Is it rea
Re: [Discuss-gnuradio] Continous Transmission using GNU RADIO. Is it really possible?
Mon, 13 May 2019 12:22:59 +0000
On Mon, 2019-05-13 at 15:03 +0300, mehtap özkan wrote:
> Dear All,
> I have implemented a CPFSK transmitter succesfully using GNU RADIO.
> The blocks are PRBS Source->Scrambler (G3RUH)-> CPFSK Mod-> UHD Sink. The
> reference HW receiver receives and demodulates the signal quite well.
It's always a nice feeling when something works with real hardware :)
> Then I remove the PRBS Source and place a UDP Source+UART block as the data
> When the connected client sends continous data, everything is fine (except at
> the start of transmission where the receiver needs time to lock to the
> incoming signal).
> When I send some bytes from the client and stop sending, the transmission
> becomes burst-like and the receiver can demodulate pretty much nothing.
> I found the culprit which is the Scrambler, when there is no input to the
> Scrambler, there is no output, so there is no RF output.
Well, I wouldn't call it a "culprit", since it does what it's designed
to do: Scramble data.
> I have also developed a FPGA Continous CPFSK transmitter in the past and the
> scrambler there was producing output every clock cycle as there was 0 in its
> Input, so that guaranteed continous output.
> The real problem is: What should I do to force some Input bits to the
> Scrambler, even there is no real data?
The gr-eventstream module might be of interest to you!
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