scripts/rtl_sdr_strength.py

   1 #!/usr/bin/env python
   2 # -*- coding: iso-8859-15 -*-
   3
   4 import sys
   5 import subprocess
   6 import re
   7 import rospy
   8 import tf
   9 import tf2_ros
  10 from time import sleep
  11
  12 rospy.init_node('wifi_strength')
  13
  14 tfBuffer = tf2_ros.Buffer()
  15 listener = tf2_ros.TransformListener(tfBuffer)
  16 regex_lq = re.compile("Link Quality=(\d*)/(\d*)")
  17 while not rospy.is_shutdown():
  18         popen = subprocess.Popen("rtl_power -f 868.2M:868.5M:10k -g 42 -i 1".split(), stdout=subprocess.PIPE)
  19         while True:
  20                 line = popen.stdout.readline()
  21                 if line == "":
  22                         break
  23                 power = line.replace("\n", "").split(",")[6:]
  24                 power = [float(s) for s in power]
  25                 pos = tfBuffer.lookup_transform("map", 'base_link', rospy.Time(0), rospy.Duration(1.0))
  26                 print '{"x":%.2f, "y":%.2f, "power": %s},' % (pos.transform.translation.x, pos.transform.translation.y, power)
  27                 sys.stdout.flush()