Merge remote-tracking branch 'origin/master'

11 files changed, 137 insertions, 90 deletions

diff --git a/doc/thesis/chapters/implementation.tex b/doc/thesis/chapters/implementation.tex
index 91a1856..04549c5 100644
--- a/doc/thesis/chapters/implementation.tex
+++ b/doc/thesis/chapters/implementation.tex
@@ -1,4 +1,4 @@
-% vim: set ts=2 sw=2 noet:
+% vim: set ts=2 sw=2 noet spell:
 
 \chapter{Implementation}
 
@@ -47,7 +47,7 @@ From the complex space the constellation points are decode to bits.
 	}
 \end{figure}
 
-To compute the empirical \emph{bit error rate} (BER) of the setup, the data has to be framed on by the sender and the bitstream synchronized on the receiver side. The structure of a data packed used in the implementation is shown in \figref{fig:dataframe}. A frame begins with an user specified \(k\)-byte preamble, that in the current implementation serves as synchronization pattern. Another use case for the preamble sequence could be to introduce channel estimation pilot symbols. Following the preamble are 4 bytes encoded using a (31, 26) Hamming code (plus 1 padding bit), that contain metadata about the packet, namely payload ID and payload length. Because the payload length in bytes is encoded in 21 bits, the maximum payload size is 2 MiB, which together with \(2^5 = 32\) possible unique IDs gives a maximum data transfer with unique frame headers of 64 MiB. These constraints are a result of decisions made to keep the implementation simple.
+To compute the empirical \emph{bit error rate} (BER) of the setup, the data has to be framed on by the sender and the bitstream synchronized on the receiver side. The structure of a data packed used in the implementation is shown in \figref{fig:dataframe}. A frame begins with an user specified \(k\)-byte preamble, that in the current implementation serves as synchronization pattern. Another use case for the preamble sequence could be to introduce channel estimation pilot symbols. Following the preamble are 4 bytes encoded using a (31, 26) Hamming code (plus 1 padding bit), that contain metadata about the packet, namely payload ID and payload length. Because the payload length in bytes is encoded in 21 bits, the maximum payload size is 2 MiB, which together with 32 possible unique IDs gives a maximum data transfer with unique frame headers of 64 MiB. These constraints are a result of decisions made to keep the implementation simple.
 
 On the receiver side the bitstream is synchronized using a XOR correlator. To find the synchronization delay \(d\) (in samples) the XOR correlator computes the binary cross correlation
 \begin{equation} \label{eqn:binary-xcorr}
diff --git a/src/gui.py b/src/gui.py
index a0db566..b2cbebb 100755
--- a/src/gui.py
+++ b/src/gui.py
@@ -13,7 +13,6 @@ import signal
 
 # Mathematics
 import numpy as np
-from numpy_ringbuffer import RingBuffer
 
 # For debugging
 import logging
@@ -37,42 +36,6 @@ setup_dearpygui()
 # Show demo for dev
 show_demo()
 
-#================================================
-# Network classes
-
-class network_plot(net.udpsource):
-    def __init__(self, url, nsamples, **kwargs):
-        net.udpsource.__init__(self, url)
-
-        self.nsamples = nsamples
-        self.plot = plot(**kwargs)
-
-        # create buffer and fill with zeroes
-        self.buffer = RingBuffer(capacity=nsamples, dtype=(np.float, 2))
-        for i in range(nsamples):
-            # TODO: remove random data used for testing
-            self.buffer.append(np.array([i, 1 + np.random.rand() / 5]))
-
-        self.bind()
-
-    def __enter__(self):
-        return self.plot.__enter__()
-
-    def __exit__(self, t, val, tb):
-        self.plot.__exit__(t, val, tb)
-
-    @property
-    def x_data(self):
-        return np.array(self.buffer[:,0])
-
-    @property
-    def y_data(self):
-        return np.array(self.buffer[:,1])
-
-    def refresh(self, series_tag):
-        # set_value(series_tag, [self.x_data, self.y_data])
-        pass
-
 
 #================================================
 # GUI Callback functions
@@ -135,8 +98,7 @@ with window(label="RX DSP Flow Graph", width=800, height=400, pos=(25,25), tag="
 #================================================
 # Network plots Window
 
-recv_plot = network_plot(url="udp://localhost:31415", nsamples=100, label="Test", height=300, width=800)
-
+recv_plot = net.network_plot(url="udp://localhost:31415", nsamples=100, label="Test", height=300, width=800)
 
 plots = {
     recv_plot: "plt_ampl"
@@ -158,7 +120,7 @@ show_viewport()
 # Main loop
 while is_dearpygui_running():
     for plt, tag in plots.items():
-        plt.refresh(tag)
+        plt.refresh_series(tag)
 
     render_dearpygui_frame()
 
diff --git a/src/net.py b/src/net.py
index 6bd71ac..2c91bb8 100644
--- a/src/net.py
+++ b/src/net.py
@@ -3,6 +3,8 @@ import socket
 from urllib.parse import urlparse
 
 import numpy as np
+from numpy_ringbuffer import RingBuffer
+import dearpygui.dearpygui as dpg
 
 
 class udpsource:
@@ -31,3 +33,36 @@ class udpsource:
         else:
             return None
 
+
+class network_plot(udpsource):
+    def __init__(self, url, nsamples, **kwargs):
+        udpsource.__init__(self, url)
+
+        self.nsamples = nsamples
+        self.plot = dpg.plot(**kwargs)
+
+        # create buffer and fill with zeroes
+        self.buffer = RingBuffer(capacity=nsamples, dtype=(float, 2))
+        for i in range(nsamples):
+            # TODO: remove random data used for testing
+            self.buffer.append(np.array([i, 1 + np.random.rand() / 5]))
+
+        self.bind()
+
+    def __enter__(self):
+        return self.plot.__enter__()
+
+    def __exit__(self, t, val, tb):
+        self.plot.__exit__(t, val, tb)
+
+    @property
+    def x_data(self):
+        return np.array(self.buffer[:,0])
+
+    @property
+    def y_data(self):
+        return np.array(self.buffer[:,1])
+
+    def refresh_series(self, tag):
+        dpg.set_value(tag, [self.x_data, self.y_data])
+        pass
diff --git a/src/nix/numpy-ringbuffer.nix b/src/nix/numpy-ringbuffer.nix
new file mode 100644
index 0000000..b97b01a
--- /dev/null
+++ b/src/nix/numpy-ringbuffer.nix
@@ -0,0 +1,12 @@
+{ lib, pkgs, buildPythonPackage, fetchPypi, isPy38, autoPatchelfHook }:
+
+buildPythonPackage rec {
+  pname = "numpy_ringbuffer";
+  version = "0.2.1";
+  src = fetchPypi {
+    inherit pname version;
+    sha256 = "1vrw38jb3cy9m0c1xxvkk5sf1hpgv58x649a2nnqi9ljdl5wcydc";
+  };
+
+  buildInputs =  (with pkgs.python3Packages; [ numpy ]);
+}
diff --git a/src/shell.nix b/src/shell.nix
index 666bab3..22771e2 100644
--- a/src/shell.nix
+++ b/src/shell.nix
@@ -7,10 +7,18 @@ let
     isPy38 = pkgs.python38Packages.isPy38;
   };
 
+  numpy-ringbuffer = callPackage ./nix/numpy-ringbuffer.nix {
+    buildPythonPackage = pkgs.python38Packages.buildPythonPackage;
+    fetchPypi = pkgs.python38Packages.fetchPypi;
+    isPy38 = pkgs.python38Packages.isPy38;
+  };
+
 in mkShell {
-  buildInputs = [ dearpygui ] ++ (with pkgs; [
+  buildInputs = [ dearpygui numpy-ringbuffer ] ++ (with pkgs; [
     gnuradio
     python38Packages.setuptools
+    python38Packages.matplotlib
+    python38Packages.numpy
     # gnuradio block dev dependencies
     cmake ninja pkg-config log4cpp mpir boost175 gmp volk doxygen
     python38Packages.pybind11
diff --git a/tests/correlator/acgen.dat b/tests/correlator/acgen.dat
index a6ad193..537dcc5 100644
--- a/tests/correlator/acgen.dat
+++ b/tests/correlator/acgen.dat
diff --git a/tests/correlator/acgen.grc b/tests/correlator/acgen.grc
index b0aa685..ec7c1e8 100644
--- a/tests/correlator/acgen.grc
+++ b/tests/correlator/acgen.grc
@@ -1,6 +1,7 @@
 options:
   parameters:
     author: Naoki Pross
+    catch_exceptions: 'True'
     category: '[GRC Hier Blocks]'
     cmake_opt: ''
     comment: ''
@@ -22,7 +23,6 @@ options:
     sizing_mode: fixed
     thread_safe_setters: ''
     title: Access Code Symbols Generator
-    window_size: ''
   states:
     bus_sink: false
     bus_source: false
@@ -36,7 +36,7 @@ blocks:
   id: variable
   parameters:
     comment: ''
-    value: '[ 0xaa, 0xff, 0xff ]'
+    value: '[ 0xaa, 0xff, 0x0a ]'
   states:
     bus_sink: false
     bus_source: false
@@ -50,6 +50,7 @@ blocks:
     comment: ''
     const_points: '[-1-1j, -1+1j, 1+1j, 1-1j]'
     dims: '1'
+    normalization: digital.constellation.AMPLITUDE_NORMALIZATION
     precision: '8'
     rot_sym: '4'
     soft_dec_lut: None
@@ -168,6 +169,7 @@ blocks:
     maxoutbuf: '0'
     minoutbuf: '0'
     samples_per_symbol: sps
+    truncate: 'False'
     verbose: 'False'
   states:
     bus_sink: false
diff --git a/tests/correlator/acgen.py b/tests/correlator/acgen.py
index f4486e4..5fbdbb4 100755
--- a/tests/correlator/acgen.py
+++ b/tests/correlator/acgen.py
@@ -7,12 +7,13 @@
 # GNU Radio Python Flow Graph
 # Title: Access Code Symbols Generator
 # Author: Naoki Pross
-# GNU Radio version: 3.8.2.0
+# GNU Radio version: 3.9.2.0
 
 from gnuradio import blocks
 from gnuradio import digital
 from gnuradio import gr
 from gnuradio.filter import firdes
+from gnuradio.fft import window
 import sys
 import signal
 from argparse import ArgumentParser
@@ -20,10 +21,12 @@ from gnuradio.eng_arg import eng_float, intx
 from gnuradio import eng_notation
 
 
+
+
 class acgen(gr.top_block):
 
     def __init__(self):
-        gr.top_block.__init__(self, "Access Code Symbols Generator")
+        gr.top_block.__init__(self, "Access Code Symbols Generator", catch_exceptions=True)
 
         ##################################################
         # Variables
@@ -32,7 +35,7 @@ class acgen(gr.top_block):
         self.samp_rate = samp_rate = 32000
         self.excess_bw = excess_bw = 1
         self.const = const = digital.constellation_qpsk().base()
-        self.access_code = access_code = [ 0xaa, 0xff, 0xff ]
+        self.access_code = access_code = [ 0xaa, 0xff, 0x0a ]
 
         ##################################################
         # Blocks
@@ -44,7 +47,8 @@ class acgen(gr.top_block):
             pre_diff_code=True,
             excess_bw=excess_bw,
             verbose=False,
-            log=False)
+            log=False,
+            truncate=False)
         self.blocks_vector_source_x_0 = blocks.vector_source_b([0x00] * 10 + access_code * 10, False, 1, [])
         self.blocks_throttle_0 = blocks.throttle(gr.sizeof_char*1, samp_rate,True)
         self.blocks_file_sink_0 = blocks.file_sink(gr.sizeof_gr_complex*1, 'acgen.dat', False)
@@ -95,7 +99,6 @@ class acgen(gr.top_block):
 
 
 
-
 def main(top_block_cls=acgen, options=None):
     tb = top_block_cls()
 
diff --git a/tests/correlator/acproc.py b/tests/correlator/acproc.py
index 5f6ace3..e119520 100755
--- a/tests/correlator/acproc.py
+++ b/tests/correlator/acproc.py
@@ -49,8 +49,9 @@ ax2.plot(ac.imag, ".-")
 ax2.set_title("Symbols of Access Code (time)")
 plt.show()
 
+fir = list(np.conj(ac[::-1]))
+
 # print the symbols
 print(f"Generated {len(ac)} symbols from a {aclen} byte sequence")
-print(list(ac))
-print("Reversed symbols (for FIR filter)")
-print(list(ac[::-1]))
+print("Reversed symbols (for FIR filter):")
+print(fir)
diff --git a/tests/correlator/correlator.grc b/tests/correlator/correlator.grc
index a5a8c89..cc57e18 100644
--- a/tests/correlator/correlator.grc
+++ b/tests/correlator/correlator.grc
@@ -1,6 +1,7 @@
 options:
   parameters:
     author: Naoki Pross
+    catch_exceptions: 'True'
     category: '[GRC Hier Blocks]'
     cmake_opt: ''
     comment: ''
@@ -22,7 +23,6 @@ options:
     sizing_mode: fixed
     thread_safe_setters: ''
     title: Correlator Test
-    window_size: ''
   states:
     bus_sink: false
     bus_source: false
@@ -38,6 +38,7 @@ blocks:
     comment: ''
     const_points: '[-1-1j, -1+1j, 1+1j, 1-1j]'
     dims: '1'
+    normalization: digital.constellation.AMPLITUDE_NORMALIZATION
     precision: '8'
     rot_sym: '4'
     soft_dec_lut: None
@@ -122,6 +123,22 @@ blocks:
     coordinate: [696, 420.0]
     rotation: 0
     state: true
+- name: blocks_complex_to_mag_0
+  id: blocks_complex_to_mag
+  parameters:
+    affinity: ''
+    alias: ''
+    comment: ''
+    maxoutbuf: '0'
+    minoutbuf: '0'
+    vlen: '1'
+  states:
+    bus_sink: false
+    bus_source: false
+    bus_structure: null
+    coordinate: [1584, 80.0]
+    rotation: 0
+    state: true
 - name: blocks_null_sink_0
   id: blocks_null_sink
   parameters:
@@ -169,7 +186,7 @@ blocks:
     repeat: 'False'
     tags: '[]'
     type: byte
-    vector: '[0x00] * 10 + [0xaa, 0xff, 0xff] + [0x00] * 10'
+    vector: ([0x00] * 10 + [0xaa, 0xff, 0x0a] + [0x00] * 10) * 20
     vlen: '1'
   states:
     bus_sink: false
@@ -196,7 +213,7 @@ blocks:
     bus_structure: null
     coordinate: [992, 188.0]
     rotation: 0
-    state: true
+    state: enabled
 - name: digital_constellation_decoder_cb_0
   id: digital_constellation_decoder_cb
   parameters:
@@ -226,6 +243,7 @@ blocks:
     maxoutbuf: '0'
     minoutbuf: '0'
     samples_per_symbol: sps
+    truncate: 'False'
     verbose: 'False'
   states:
     bus_sink: false
@@ -267,17 +285,17 @@ blocks:
     maxoutbuf: '0'
     minoutbuf: '0'
     samp_delay: '0'
-    taps: '[(1.4142197+1.4142197j), (1.4142197+1.4142197j), (1.4142197+1.4142197j),
-      (1.4142197+1.4142197j), (1.4142197+1.4142197j), (1.4142197+1.4142197j), (-1.4142197+1.4142197j),
-      (-1.4142197+1.4142197j), (-1.4142197+1.4142197j), (-1.4142197+1.4142197j), (1.4142197+1.4142197j),
-      (1.4142197+1.4142197j), (1.4142197+1.4142197j), (1.4142197+1.4142197j), (1.4142197+1.4142197j),
-      (1.4142197+1.4142197j)]'
+    taps: '[(-1.4142197+1.4142197j), (-1.4142197+1.4142197j), (1.4142197-1.4142197j),
+      (1.4142197-1.4142197j), (1.4142197-1.4142197j), (1.4142197-1.4142197j), (-1.4142197-1.4142197j),
+      (-1.4142197-1.4142197j), (-1.4142197-1.4142197j), (-1.4142197-1.4142197j), (-1.4142197-1.4142197j),
+      (-1.4142197-1.4142197j), (-1.4142197+1.4142197j), (-1.4142197+1.4142197j), (1.4142197-1.4142197j),
+      (1.4142197-1.4142197j)]'
     type: ccc
   states:
     bus_sink: false
     bus_source: false
     bus_structure: null
-    coordinate: [1240, 76.0]
+    coordinate: [1328, 68.0]
     rotation: 0
     state: enabled
 - name: qtgui_time_sink_x_0
@@ -354,7 +372,7 @@ blocks:
     tr_mode: qtgui.TRIG_MODE_FREE
     tr_slope: qtgui.TRIG_SLOPE_POS
     tr_tag: '""'
-    type: complex
+    type: float
     update_time: '0.10'
     width1: '1'
     width10: '1'
@@ -367,14 +385,14 @@ blocks:
     width8: '1'
     width9: '1'
     ylabel: Amplitude
-    ymax: '2'
-    ymin: '-2'
+    ymax: '50'
+    ymin: '0'
     yunit: '""'
   states:
     bus_sink: false
     bus_source: false
     bus_structure: null
-    coordinate: [1488, 68.0]
+    coordinate: [1792, 60.0]
     rotation: 0
     state: true
 - name: qtgui_time_sink_x_1
@@ -476,6 +494,7 @@ blocks:
     state: true
 
 connections:
+- [blocks_complex_to_mag_0, '0', qtgui_time_sink_x_0, '0']
 - [blocks_throttle_0, '0', digital_constellation_modulator_0, '0']
 - [blocks_vector_source_x_0, '0', blocks_throttle_0, '0']
 - [digital_cma_equalizer_cc_0, '0', digital_constellation_decoder_cb_0, '0']
@@ -484,7 +503,7 @@ connections:
 - [digital_constellation_modulator_0, '0', digital_pfb_clock_sync_xxx_0, '0']
 - [digital_constellation_modulator_0, '0', qtgui_time_sink_x_1, '0']
 - [digital_pfb_clock_sync_xxx_0, '0', digital_cma_equalizer_cc_0, '0']
-- [fir_filter_xxx_1, '0', qtgui_time_sink_x_0, '0']
+- [fir_filter_xxx_1, '0', blocks_complex_to_mag_0, '0']
 
 metadata:
   file_format: 1
diff --git a/tests/correlator/correlator.py b/tests/correlator/correlator.py
index b0cef0e..79fa3f8 100755
--- a/tests/correlator/correlator.py
+++ b/tests/correlator/correlator.py
@@ -7,7 +7,7 @@
 # GNU Radio Python Flow Graph
 # Title: Correlator Test
 # Author: Naoki Pross
-# GNU Radio version: 3.8.2.0
+# GNU Radio version: 3.9.2.0
 
 from distutils.version import StrictVersion
 
@@ -29,18 +29,21 @@ from gnuradio import blocks
 from gnuradio import digital
 from gnuradio import filter
 from gnuradio import gr
+from gnuradio.fft import window
 import sys
 import signal
 from argparse import ArgumentParser
 from gnuradio.eng_arg import eng_float, intx
 from gnuradio import eng_notation
 
+
+
 from gnuradio import qtgui
 
 class correlator(gr.top_block, Qt.QWidget):
 
     def __init__(self):
-        gr.top_block.__init__(self, "Correlator Test")
+        gr.top_block.__init__(self, "Correlator Test", catch_exceptions=True)
         Qt.QWidget.__init__(self)
         self.setWindowTitle("Correlator Test")
         qtgui.util.check_set_qss()
@@ -88,7 +91,8 @@ class correlator(gr.top_block, Qt.QWidget):
             1024, #size
             samp_rate, #samp_rate
             "", #name
-            1 #number of inputs
+            1, #number of inputs
+            None # parent
         )
         self.qtgui_time_sink_x_1.set_update_time(0.10)
         self.qtgui_time_sink_x_1.set_y_axis(-2, 2)
@@ -133,15 +137,16 @@ class correlator(gr.top_block, Qt.QWidget):
             self.qtgui_time_sink_x_1.set_line_alpha(i, alphas[i])
 
         self._qtgui_time_sink_x_1_win = sip.wrapinstance(self.qtgui_time_sink_x_1.pyqwidget(), Qt.QWidget)
-        self.top_grid_layout.addWidget(self._qtgui_time_sink_x_1_win)
-        self.qtgui_time_sink_x_0 = qtgui.time_sink_c(
+        self.top_layout.addWidget(self._qtgui_time_sink_x_1_win)
+        self.qtgui_time_sink_x_0 = qtgui.time_sink_f(
             1024, #size
             samp_rate, #samp_rate
             "", #name
-            1 #number of inputs
+            1, #number of inputs
+            None # parent
         )
         self.qtgui_time_sink_x_0.set_update_time(0.10)
-        self.qtgui_time_sink_x_0.set_y_axis(-2, 2)
+        self.qtgui_time_sink_x_0.set_y_axis(0, 50)
 
         self.qtgui_time_sink_x_0.set_y_label('Amplitude', "")
 
@@ -168,12 +173,9 @@ class correlator(gr.top_block, Qt.QWidget):
             -1, -1, -1, -1, -1]
 
 
-        for i in range(2):
+        for i in range(1):
             if len(labels[i]) == 0:
-                if (i % 2 == 0):
-                    self.qtgui_time_sink_x_0.set_line_label(i, "Re{{Data {0}}}".format(i/2))
-                else:
-                    self.qtgui_time_sink_x_0.set_line_label(i, "Im{{Data {0}}}".format(i/2))
+                self.qtgui_time_sink_x_0.set_line_label(i, "Data {0}".format(i))
             else:
                 self.qtgui_time_sink_x_0.set_line_label(i, labels[i])
             self.qtgui_time_sink_x_0.set_line_width(i, widths[i])
@@ -183,8 +185,8 @@ class correlator(gr.top_block, Qt.QWidget):
             self.qtgui_time_sink_x_0.set_line_alpha(i, alphas[i])
 
         self._qtgui_time_sink_x_0_win = sip.wrapinstance(self.qtgui_time_sink_x_0.pyqwidget(), Qt.QWidget)
-        self.top_grid_layout.addWidget(self._qtgui_time_sink_x_0_win)
-        self.fir_filter_xxx_1 = filter.fir_filter_ccc(1, [(1.4142197+1.4142197j), (1.4142197+1.4142197j), (1.4142197+1.4142197j), (1.4142197+1.4142197j), (1.4142197+1.4142197j), (1.4142197+1.4142197j), (-1.4142197+1.4142197j), (-1.4142197+1.4142197j), (-1.4142197+1.4142197j), (-1.4142197+1.4142197j), (1.4142197+1.4142197j), (1.4142197+1.4142197j), (1.4142197+1.4142197j), (1.4142197+1.4142197j), (1.4142197+1.4142197j), (1.4142197+1.4142197j)])
+        self.top_layout.addWidget(self._qtgui_time_sink_x_0_win)
+        self.fir_filter_xxx_1 = filter.fir_filter_ccc(1, [(-1.4142197+1.4142197j), (-1.4142197+1.4142197j), (1.4142197-1.4142197j), (1.4142197-1.4142197j), (1.4142197-1.4142197j), (1.4142197-1.4142197j), (-1.4142197-1.4142197j), (-1.4142197-1.4142197j), (-1.4142197-1.4142197j), (-1.4142197-1.4142197j), (-1.4142197-1.4142197j), (-1.4142197-1.4142197j), (-1.4142197+1.4142197j), (-1.4142197+1.4142197j), (1.4142197-1.4142197j), (1.4142197-1.4142197j)])
         self.fir_filter_xxx_1.declare_sample_delay(0)
         self.digital_pfb_clock_sync_xxx_0 = digital.pfb_clock_sync_ccf(sps, timing_loop_bw, rrc_taps, nfilts, 16, 1.5, 1)
         self.digital_constellation_modulator_0 = digital.generic_mod(
@@ -194,18 +196,21 @@ class correlator(gr.top_block, Qt.QWidget):
             pre_diff_code=True,
             excess_bw=excess_bw,
             verbose=False,
-            log=False)
+            log=False,
+            truncate=False)
         self.digital_constellation_decoder_cb_0 = digital.constellation_decoder_cb(const)
         self.digital_cma_equalizer_cc_0 = digital.cma_equalizer_cc(15, 1, .002, 1)
-        self.blocks_vector_source_x_0 = blocks.vector_source_b([0x00] * 10 + [0xaa, 0xff, 0xff] + [0x00] * 10, False, 1, [])
+        self.blocks_vector_source_x_0 = blocks.vector_source_b(([0x00] * 10 + [0xaa, 0xff, 0x0a] + [0x00] * 10) * 20, False, 1, [])
         self.blocks_throttle_0 = blocks.throttle(gr.sizeof_char*1, samp_rate,True)
         self.blocks_null_sink_0 = blocks.null_sink(gr.sizeof_char*1)
+        self.blocks_complex_to_mag_0 = blocks.complex_to_mag(1)
 
 
 
         ##################################################
         # Connections
         ##################################################
+        self.connect((self.blocks_complex_to_mag_0, 0), (self.qtgui_time_sink_x_0, 0))
         self.connect((self.blocks_throttle_0, 0), (self.digital_constellation_modulator_0, 0))
         self.connect((self.blocks_vector_source_x_0, 0), (self.blocks_throttle_0, 0))
         self.connect((self.digital_cma_equalizer_cc_0, 0), (self.digital_constellation_decoder_cb_0, 0))
@@ -214,12 +219,15 @@ class correlator(gr.top_block, Qt.QWidget):
         self.connect((self.digital_constellation_modulator_0, 0), (self.digital_pfb_clock_sync_xxx_0, 0))
         self.connect((self.digital_constellation_modulator_0, 0), (self.qtgui_time_sink_x_1, 0))
         self.connect((self.digital_pfb_clock_sync_xxx_0, 0), (self.digital_cma_equalizer_cc_0, 0))
-        self.connect((self.fir_filter_xxx_1, 0), (self.qtgui_time_sink_x_0, 0))
+        self.connect((self.fir_filter_xxx_1, 0), (self.blocks_complex_to_mag_0, 0))
 
 
     def closeEvent(self, event):
         self.settings = Qt.QSettings("GNU Radio", "correlator")
         self.settings.setValue("geometry", self.saveGeometry())
+        self.stop()
+        self.wait()
+
         event.accept()
 
     def get_sps(self):
@@ -275,7 +283,6 @@ class correlator(gr.top_block, Qt.QWidget):
 
 
 
-
 def main(top_block_cls=correlator, options=None):
 
     if StrictVersion("4.5.0") <= StrictVersion(Qt.qVersion()) < StrictVersion("5.0.0"):
@@ -290,6 +297,9 @@ def main(top_block_cls=correlator, options=None):
     tb.show()
 
     def sig_handler(sig=None, frame=None):
+        tb.stop()
+        tb.wait()
+
         Qt.QApplication.quit()
 
     signal.signal(signal.SIGINT, sig_handler)
@@ -299,11 +309,6 @@ def main(top_block_cls=correlator, options=None):
     timer.start(500)
     timer.timeout.connect(lambda: None)
 
-    def quitting():
-        tb.stop()
-        tb.wait()
-
-    qapp.aboutToQuit.connect(quitting)
     qapp.exec_()
 
 if __name__ == '__main__':