METEOR initial flowgraph

This commit adds a inital METEOR flowgraph that can be used for
capturing raw IQ. The capturing is performed in a sampling rate of
320KSPS which is more than enough for actual decoding for both METEOR
modes (72K and 80K). Due to icnreased bandwidth no audio file is
generated.

apps/flowgraphs/satellites/CMakeLists.txt

@@ -23,5 +23,6 @@ GR_PYTHON_INSTALL(
     PROGRAMS
     upsat_transceiver_cli.py
     satnogs_noaa_apt_decoder.py
+    satnogs_meteor_decoder.py
     DESTINATION bin
 )

python/CMakeLists.txt

@@ -34,6 +34,7 @@ GR_PYTHON_INSTALL(
     dsp_settings.py
     hw_settings.py
     satnogs_upsat_transmitter.py
+    utils.py
     DESTINATION ${GR_PYTHON_DIR}/satnogs
 )
 

python/__init__.py

@@ -31,6 +31,7 @@ try:
     from dsp_settings import *
     from hw_settings import *
     from satnogs_upsat_transmitter import *
+    from utils import *
 except ImportError as err:
     sys.stderr.write("Failed to import SatNOGS ({})\n".format(err))
     sys.stderr.write("Consider first to run 'sudo ldconfig'\n")

python/utils.py

@@ -0,0 +1,30 @@
+#! /usr/bin/python
+#
+# gr-satnogs: SatNOGS GNU Radio Out-Of-Tree Module
+#
+#  Copyright (C) 2018
+#  Libre Space Foundation <http://librespacefoundation.org/>
+#
+#  This program is free software: you can redistribute it and/or modify
+#  it under the terms of the GNU General Public License as published by
+#  the Free Software Foundation, either version 3 of the License, or
+#  (at your option) any later version.
+#
+#  This program is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#  GNU General Public License for more details.
+#
+#  You should have received a copy of the GNU General Public License
+#  along with this program.  If not, see <http://www.gnu.org/licenses/>
+#
+
+def lcm(p,q):
+    p, q = abs(p), abs(q)
+    m = p * q
+    if not m: return 0
+    while True:
+        p %= q
+        if not p: return m // q
+        q %= p
+        if not q: return m // p