Seamless waveform switching

GNU Radio
1

I was wondering if I could get some help with a few questions I have
that I have yet to find answers for:

  1. Is there a way to stop transmission only after transmitting the
    complete waveform? Let me elaborate. I specify a wave into a vector
    source. I want to repeat transmission of this source until I tell it to
    stop, however, I want it to complete the transmission of that source
    before it ceases when I call Stop().

  2. Is there a method established already for seamlessly switching
    vector sources without ceasing transmission. If I pre-specify a new
    vector source, can I switch between the old and new without stopping,
    disconnecting old source, connecting new source, and restarting the
    flowgraph. I get about a .5 second delay (which I would like to
    mitigate as much as possible) between the end of the old source and the
    beginning of the new one.

This problem, however, seems less harmful than being able to complete
the waveform(question 1) before stopping.

Sean

2

Sean Christopher Young schrieb:

  1. Is there a method established already for seamlessly switching
    vector sources without ceasing transmission.

You could use two multipliers and a adder and use this as a switch:

         ,--------.

Source1 —>| Multi1 |–|
--------´ |--->,-------. | Adder |--->Sink ,--------. |--->-------´
Source2 —>| Multi2 |–|
`--------´

You start with multiplication factors 1 and 0, respectively.
To switch you set the multiplication of the first multiplier to 0 and
the second to 1. This will not align your waveforms, but at least you
get a decently fast swtiching.

Patrick

–
Engineers motto: cheap, good, fast: choose any two
Patrick S.
Student of Telematik, Techn. University Graz, Austria