SYNOPSIS

gr_plot_psd: [options] input_filename

DESCRIPTION

Takes a GNU Radio binary file (with specified data type using --data-type) and displays the I&Q data versus time as well as the power spectral density (PSD) plot. The y-axis values are plotted assuming volts as the amplitude of the I&Q streams and converted into dBm in the frequency domain (the 1/N power adjustment out of the FFT is performed internally). The script plots a certain block of data at a time, specified on the command line as -B or --block. The start position in the file can be set by specifying -s or --start and defaults to 0 (the start of the file). By default, the system assumes a sample rate of 1, so in time, each sample is plotted versus the sample number. To set a true time and frequency axis, set the sample rate (-R or --sample-rate) to the sample rate used when capturing the samples. Finally, the size of the FFT to use for the PSD and spectrogram plots can be set independently with --psd-size and --spec-size, respectively. The spectrogram plot does not display by default and is turned on with -S or --enable-spec.

OPTIONS

-h, --help

show this help message and exit

-d DATA_TYPE, --data-type=DATA_TYPE

Specify the data type (complex64, float32, (u)int32, (u)int16, (u)int8) [default=complex64]

-B BLOCK, --block=BLOCK

Specify the block size [default=8192]

-s START, --start=START

Specify where to start in the file [default=0]

-R SAMPLE_RATE, --sample-rate=SAMPLE_RATE

Set the sampler rate of the data [default=1.0]

--psd-size=PSD_SIZE

Set the size of the PSD FFT [default=1024]

--spec-size=SPEC_SIZE

Set the size of the spectrogram FFT [default=256]

-S, --enable-spec

Turn on plotting the spectrogram [default=False]