Re: [Discuss-gnuradio] Bypass work function

[bob wole]

Well, in my case the tx/rx would not be stationary, so the channel is not quite. 

--

Bob

If you can tolerate the stream stopping, use Power Squelch. Otherwise,
time to dive in and follow Tom's advice from May - disable the CMA taps
update loop when there's no signal. This whole idea assumes you have a
mostly quiet channel, stationary tx/rx, etc. Interested to hear what you
come up with.

- Jeff

On 10/01/2014 11:24 PM, bob wole wrote:
> I applied this and this is useful in condition when you do not want to
> process noise, because it is being multiplied by zero when there is no
> signal. But I want that CMA taps remain unchanged when there is no
> signal or just noise. In the above scenario CMA taps change due to
> presence of noise, because it tries to equalize noise as well.  Thanks
> for your comment.
>
> --
> Bob
>
> On Mon, Sep 29, 2014 at 7:19 PM, Jeff Long <address@hidden
> <mailto:address@hidden>> wrote:
>
>     Try using a "threshold" off the "mag squared" and feed that into a
>     multiplier after block2 (with appropriate type adapters). As long as
>     block2 doesn't have a huge delay or do rate changes, this should work.
>
>     - Jeff
>
>     On 09/29/2014 10:23 AM, bob wole wrote:
>     > Hi thanks for your comment. block2 is the gnuradio "CMA equalizer
>     > block". I want the CMA block to remain quiet when there is no signal of
>     > interest.
>     >
>     > Bob
>     >
>     >
>     >     Bob,
>     >
>     >     Saw this the other day, but there isn't a lot to go on here. If block2
>     >     is your own, you can make it do the bypass. You can also use some of the
>     >     logic blocks and a multiplier depending on what you're doing. There
>     >     isn't really a concept of on-the-fly switching in GNU Radio.
>     >
>     >     - Jeff
>     >
>     >     On 09/26/2014 01:02 PM, bob wole wrote:
>     >      >
>     >      > People, any ideas on it?
>     >      >
>     >      > --
>     >      > Bob
>     >      >
>     >      > On Wed, Sep 24, 2014 at 12:04 PM, bob wole <address@hidden <mailto:address@hidden>
>     >     <mailto:address@hidden <mailto:address@hidden>>
>      >      > <mailto:address@hidden <mailto:address@hidden>
>     <mailto:address@hidden <mailto:address@hidden>>>> wrote:
>      >      >
>      >      >       I have following flowgraph:
>      >      >
>      >      >
>      >      >
>       usrp_source--->>probe_mag_squared_block---->block2--->block3
>      >      >
>      >      >     What I want to do is that I want to bypass the "work"
>     function of
>      >      >     block2 when the threshold level of probe_mag_squared
>     reaches.
>      >     I do
>      >      >     not want to stop(), lock(), disconnect the flow graph.
>     Is this
>      >      >     possible using stream tags, or message passing etc ?
>     Any example
>      >      >     code would be nice.
>      >      >
>      >      >     --
>      >      >     Bob