Scan region of RF spectrum using rtl_power_fftw

scan.sh

#!/bin/bash

reset

# FFT bin size for a sample rate of 2,400,000 Hz:
#
# Bin Count	        Bin Width (Hz)          Bin Width (kHz)
#       4	        600,000.000	        600.000
#	8	        300,000.000	        300.000
#	16	        150,000.000	        150.000
#	32	        75,000.000	        75.000
#	64	        37,500.000	        37.500
#	128	        18,750.000	        18.750
#	256	        9,375.000	        9.375
#	512	        4,687.500	        4.688
#	1,024	        2,343.750	        2.344
#	2,048	        1,171.875	        1.172
#	4,096	        585.938	                0.586
#	8,192	        292.969	                0.293
#	16,384	        146.484	                0.146
#	32,768	        73.242	                0.073
#	65,536	        36.621	                0.037
#	131,072	        18.311	                0.018
#	262,144	        9.155	                0.009
#	524,288	        4.578	                0.005
#	1,048,576       2.289	                0.002

# rtl_power_fftw parameters
SAMPLE_RATE=2400000
FFT_SIZE=1024
START_FREQ=929000000
STEP=$(($SAMPLE_RATE / 2))
END_FREQ=939000000
INTEGRATION_TIME=86400

# Working and output paths
BASE_PATH="/workdrive/rtl_power_fftw/plot/"
WORK_PATH="$BASE_PATH/$START_FREQ-$END_FREQ"

# Exit if base path doesn't exist
if [[ ! -e $BASE_PATH ]]; then
        echo "Base path doesn't exist! Exiting."
        exit
fi

# Create work path if needed
mkdir -p $WORK_PATH

# Show frequency hops
for i in `seq $START_FREQ $STEP $END_FREQ`;
do
        echo "Tune to $i for $INTEGRATION_TIME seconds"
done 

# Do it
for i in `seq $START_FREQ $STEP $END_FREQ`;
do
        ./rtl_power_fftw -b $FFT_SIZE -f $i -g 496 -r $SAMPLE_RATE -t $INTEGRATION_TIME | \
                tee "$WORK_PATH/$i.txt" | \
                gnuplot -e "set term pngcairo size 1600,900; \
                set key font ',8'; \
                set xtics font 'Verdana,8'; \
                set format x '%.3s%c'; \
                unset key; \
                set xtics 125000; \
                set grid x y; \
                show grid; \
                set yrange [-70:0]; \
                plot '-' w l" > "$WORK_PATH/$i.png"
done