discuss-gnuradio
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Discuss-gnuradio] Enable/Disable TX ports in B210 in 2x2 setup


From: Ayaz Mahmud
Subject: Re: [Discuss-gnuradio] Enable/Disable TX ports in B210 in 2x2 setup
Date: Sat, 14 Jul 2018 22:40:14 +0000

Hi Muller / Marcus,

 

I got the testing right now, but unfortunately it doesn’t work while I put it in my original file.

 

Here is the attached .grc where I have used vector source as input and multiply a period with 1 and then with zeros on one radio channel and opposite on the other.

 

Can you please have a look, and check if I am doing anything wrong ?

 

Ayaz

 


From: Discuss-gnuradio <discuss-gnuradio-bounces+address@hidden> on behalf of Ayaz Mahmud <address@hidden>
Sent: Saturday, July 14, 2018 10:58:12 AM
To: Müller, Marcus (CEL); address@hidden; address@hidden
Subject: Re: [Discuss-gnuradio] Enable/Disable TX ports in B210 in 2x2 setup
 

Hey Muller / Marcus,

 

Yeah I also agree that multiplying with zeros and ones might be the easy way out !

 

This might sound very silly, but I was trying to implement & test this scenario in simple flow graph, where I have a signal source (sine wave with 1Khz, sample rate of 50K) and a vector source (0,1). Multiplying this both with a 2 i/p multiply block and o/p to a wx gui.

 

I was expecting to see one full period of sine wave and then 1 period of zero. But it is not the case. I believe I am not taking into consideration of the time period when multiplying with vector source (as it does not have any time period of till which it should multiply 1s). And I am not sure how to do that.

 

Can you please give me a clue 😊

 

Ayaz

 

 

From: Müller, Marcus (CEL)
Sent: Saturday, July 14, 2018 6:36 AM
To: address@hidden; address@hidden; address@hidden
Subject: Re: [Discuss-gnuradio] Enable/Disable TX ports in B210 in 2x2 setup

 

Hey Marcus,

 

yep, good catch: 64 kHz is far too low a sampling rate; Ayaz, start

with something like 1 MS/s. (also, what kind of CSI will you be getting

when observing a 64 kHz wide channel?

Are you looking for reflections that have a path length difference

larger than (sandy gears turning in my head… ) more than 4.6 km?

 

(by the way, your 1 kHz OFDM subcarrier spacing is something that you'd

actually encounter in digital broadcast standards – DAB/DAB+ does

exactly that, and that 1 kHz essentially allows for delay spread of up

to 300 km)

 

I'd agree, the easiest solution here would be just splitting your

output sample stream in two, and multiplying one with 0 while the other

is 1, and vice versa.

 

 

Best regards,

Marcus (the other one)

 

On Fri, 2018-07-13 at 15:20 -0400, Marcus D. Leech wrote:

> On 07/13/2018 01:08 PM, Ayaz Mahmud wrote:

> > Hi Marcus,

> > 

> > Here the .grc file. You might have to change the File Source (tx) &

> > destination folder(rx)

> > 

> > Ayaz

> > 

> >

>  I get that you want to alternate "active" antennae, and there are

> probably burst-tagging schemes that will do this, but I'm not an

> expert on those.

>

> I'll also observe that you're asking for a 64K sample-rate.  I'm not

> sure that the B210 will go down that low in sample rate, so you may

> have to

>   interpolate up to the minimum sample rate.

>

> If it were *my* problem, I'd probably have a couple of vector sources

> of alternating 1s and 0s, interpolate them up to the desired sample

> rate

>    X the switching interval, and multiply the stream going into the

> USRP by that stream of 1s and 0s.

>

>

> _______________________________________________

> Discuss-gnuradio mailing list

> address@hidden

> https://lists.gnu.org/mailman/listinfo/discuss-gnuradio

 

Attachment: 123123.grc
Description: 123123.grc


reply via email to

[Prev in Thread] Current Thread [Next in Thread]