Hi to everyone,
I need to plot the PSD of a L band signal and I don't know how to define
the timeline without having this error: "Maximum variable size allowed by the
program is exceeded".
The point is that I have problems with memory due to the high frequency I'm
using. If the carrier is 1.3 GHz, the sampling frequency must be 3 or 4 times
higher and matlab runs out of space and, therefore, the timeline has too many
samples.
fc= 1278.75e6;
fb00;
fch=5.115e6;
fs*fc;
Ts=1/fs;
Tb=1/fb;
Tch=1/fch;
b100e-3;
t=0:Ts:(b*Tb)-Ts;
Then, I cannot implement the BPSK signal I want to do because I have the error
with the timeline.
Any hints?
Thanks!
How to implement the timeline with a L band signal
Started by ●January 2, 2009
Reply by ●January 7, 20092009-01-07
If you are capturing this data from some real-time system, you
shouldn't process the information it contains on the carrier
frequency. Downconvert it to baseband and then downsample it. Now, it
will be appropriate for your use as far as no. of samples are concerned.
Moreover, the sampling frequency doesn't need to be 3 or 4 times the
maximum frequency in the signal. You can you use band pass sampling if
you know the bandwidth. In this case too, you need to down sample it.
If you dont wanna do any of the above mentioned things, you have to
process the data in discrete steps. Take a chunk, process it, and wait
for the results, then take another, process it and so on ...
Ubaid Abdullah
http://dspdotcomm.blogspot.com
--- In m..., rogercanalda@... wrote:
>
> Hi to everyone,
>
> I need to plot the PSD of a L band signal and I don't know how to
define the timeline without having this error: "Maximum variable size
allowed by the program is exceeded".
>
> The point is that I have problems with memory due to the high
frequency I'm using. If the carrier is 1.3 GHz, the sampling frequency
must be 3 or 4 times higher and matlab runs out of space and,
therefore, the timeline has too many samples.
>
> fc= 1278.75e6;
> fb00;
> fch=5.115e6;
> fs*fc;
> Ts=1/fs;
> Tb=1/fb;
> Tch=1/fch;
> b100e-3;
> t=0:Ts:(b*Tb)-Ts;
>
> Then, I cannot implement the BPSK signal I want to do because I have
the error with the timeline.
>
> Any hints?
>
> Thanks!
>
shouldn't process the information it contains on the carrier
frequency. Downconvert it to baseband and then downsample it. Now, it
will be appropriate for your use as far as no. of samples are concerned.
Moreover, the sampling frequency doesn't need to be 3 or 4 times the
maximum frequency in the signal. You can you use band pass sampling if
you know the bandwidth. In this case too, you need to down sample it.
If you dont wanna do any of the above mentioned things, you have to
process the data in discrete steps. Take a chunk, process it, and wait
for the results, then take another, process it and so on ...
Ubaid Abdullah
http://dspdotcomm.blogspot.com
--- In m..., rogercanalda@... wrote:
>
> Hi to everyone,
>
> I need to plot the PSD of a L band signal and I don't know how to
define the timeline without having this error: "Maximum variable size
allowed by the program is exceeded".
>
> The point is that I have problems with memory due to the high
frequency I'm using. If the carrier is 1.3 GHz, the sampling frequency
must be 3 or 4 times higher and matlab runs out of space and,
therefore, the timeline has too many samples.
>
> fc= 1278.75e6;
> fb00;
> fch=5.115e6;
> fs*fc;
> Ts=1/fs;
> Tb=1/fb;
> Tch=1/fch;
> b100e-3;
> t=0:Ts:(b*Tb)-Ts;
>
> Then, I cannot implement the BPSK signal I want to do because I have
the error with the timeline.
>
> Any hints?
>
> Thanks!
>