Add main.py and basic functions to get measurement

1 files changed, 104 insertions, 0 deletions

diff --git a/dpd/src/Measure.py b/dpd/src/Measure.py
new file mode 100644
index 0000000..a8da137
--- /dev/null
+++ b/dpd/src/Measure.py
@@ -0,0 +1,104 @@
+# The MIT License (MIT)
+#
+# Copyright (c) 2017 Andreas Steger
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+import sys
+import socket
+import struct
+import numpy as np
+import matplotlib.pyplot as pp
+from matplotlib.animation import FuncAnimation
+import argparse
+import os
+import time
+import logging
+import Dab_Util as DU
+
+class Measure:
+    """Collect Measurement from DabMod"""
+    def __init__(self, port, num_samples_to_request):
+        """"""
+        logging.info("Initalized Measure class")
+        self.sizeof_sample = 8 # complex floats
+        self.port = port
+        self.num_samples_to_request = num_samples_to_request
+
+    def _recv_exact(self, sock, num_bytes):
+        """Interfaces the socket to receive a byte string
+        
+        Args:
+            sock (socket): Socket to receive data from.
+            num_bytes (int): Number of bytes that will be returned.
+        """
+        bufs = []
+        while num_bytes > 0:
+            b = sock.recv(num_bytes)
+            if len(b) == 0:
+                break
+            num_bytes -= len(b)
+            bufs.append(b)
+        return b''.join(bufs)
+
+    def get_samples(self):
+        """Connect to ODR-DabMod, retrieve TX and RX samples, load
+        into numpy arrays, and return a tuple
+        (tx_timestamp, tx_samples, rx_timestamp, rx_samples)
+        where the timestamps are doubles, and the samples are numpy
+        arrays of complex floats, both having the same size
+        """
+        s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+        s.connect(('localhost', self.port))
+
+        logging.debug("Send version");
+        s.sendall(b"\x01")
+
+        logging.debug("Send request for {} samples".format(self.num_samples_to_request))
+        s.sendall(struct.pack("=I", self.num_samples_to_request))
+
+        logging.debug("Wait for TX metadata")
+        num_samps, tx_second, tx_pps = struct.unpack("=III", self._recv_exact(s, 12))
+        tx_ts = tx_second + tx_pps / 16384000.0
+
+        if num_samps > 0:
+            logging.debug("Receiving {} TX samples".format(num_samps))
+            txframe_bytes = self._recv_exact(s, num_samps * self.sizeof_sample)
+            txframe = np.fromstring(txframe_bytes, dtype=np.complex64)
+        else:
+            txframe = np.array([], dtype=np.complex64)
+
+        logging.debug("Wait for RX metadata")
+        rx_second, rx_pps = struct.unpack("=II", self._recv_exact(s, 8))
+        rx_ts = rx_second + rx_pps / 16384000.0
+
+        if num_samps > 0:
+            logging.debug("Receiving {} RX samples".format(num_samps))
+            rxframe_bytes = self._recv_exact(s, num_samps * self.sizeof_sample)
+            rxframe = np.fromstring(rxframe_bytes, dtype=np.complex64)
+        else:
+            rxframe = np.array([], dtype=np.complex64)
+
+        logging.debug("Disconnecting")
+        s.close()
+
+        logging.info("Measurement done, txframe %d %s, rxframe %d %s" % (len(txframe), txframe.dtype, len(rxframe), rxframe.dtype) )
+        du = DU.Dab_Util(8192000)
+        txframe_aligned, rxframe_aligned = du.subsample_align(txframe, rxframe)
+        return txframe_aligned, rxframe_aligned