diff --git a/include/ieee802-11/CMakeLists.txt b/include/ieee802-11/CMakeLists.txt
index 159c3c6..c7e375e 100644
--- a/include/ieee802-11/CMakeLists.txt
+++ b/include/ieee802-11/CMakeLists.txt
@@ -70,6 +70,7 @@ list(APPEND include_sources
     ${generated_includes}
     api.h
     chunks_to_symbols.h
+    constellations.h
     decode_mac.h
     decode_signal.h
     equalize_symbols.h
diff --git a/include/ieee802-11/constellations.h b/include/ieee802-11/constellations.h
new file mode 100644
index 0000000..bcc79a5
--- /dev/null
+++ b/include/ieee802-11/constellations.h
@@ -0,0 +1,71 @@
+/*
+ * Copyright (C) 2016 Bastian Bloessl <bloessl@ccs-labs.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/>.
+ */
+
+#ifndef INCLUDED_IEEE802_11_CONSTELLATIONS_H
+#define INCLUDED_IEEE802_11_CONSTELLATIONS_H
+
+#include <ieee802-11/api.h>
+#include <gnuradio/digital/constellation.h>
+
+namespace gr {
+namespace ieee802_11 {
+
+class IEEE802_11_API constellation_bpsk : virtual public digital::constellation
+{
+public:
+	typedef boost::shared_ptr<gr::ieee802_11::constellation_bpsk> sptr;
+	static sptr make();
+
+protected:
+	constellation_bpsk();
+};
+
+class IEEE802_11_API constellation_qpsk : virtual public digital::constellation
+{
+public:
+	typedef boost::shared_ptr<gr::ieee802_11::constellation_qpsk> sptr;
+	static sptr make();
+
+protected:
+	constellation_qpsk();
+};
+
+class IEEE802_11_API constellation_16qam : virtual public digital::constellation
+{
+public:
+	typedef boost::shared_ptr<gr::ieee802_11::constellation_16qam> sptr;
+	static sptr make();
+
+protected:
+	constellation_16qam();
+};
+
+class IEEE802_11_API constellation_64qam : virtual public digital::constellation
+{
+public:
+	typedef boost::shared_ptr<gr::ieee802_11::constellation_64qam> sptr;
+	static sptr make();
+
+protected:
+	constellation_64qam();
+};
+
+} // namespace ieee802_11
+} // namespace gr
+
+#endif /* INCLUDED_IEEE802_11_CONSTELLATIONS_H */
+
diff --git a/lib/CMakeLists.txt b/lib/CMakeLists.txt
index fca0ec2..c2abad8 100644
--- a/lib/CMakeLists.txt
+++ b/lib/CMakeLists.txt
@@ -95,7 +95,7 @@ add_dependencies(ieee802_11_generated_sources ieee802_11_generated_includes)
 list(APPEND gr_ieee802_11_sources
     ${generated_sources}
     chunks_to_symbols_impl.cc
-    constellations.cc
+    constellations_impl.cc
     decode_mac.cc
     decode_signal.cc
     equalize_symbols.cc
diff --git a/lib/constellations_impl.cc b/lib/constellations_impl.cc
new file mode 100644
index 0000000..6f7792d
--- /dev/null
+++ b/lib/constellations_impl.cc
@@ -0,0 +1,235 @@
+/*
+ * Copyright (C) 2016 Bastian Bloessl <bloessl@ccs-labs.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/>.
+ */
+#include "constellations_impl.h"
+
+using namespace gr::ieee802_11;
+
+constellation_bpsk::sptr
+constellation_bpsk::make() {
+	return constellation_bpsk::sptr(new constellation_bpsk_impl());
+}
+
+constellation_bpsk::constellation_bpsk() {}
+
+constellation_bpsk_impl::constellation_bpsk_impl() {
+	d_constellation.resize(2);
+	d_constellation[0] = gr_complex(-1, 0);
+	d_constellation[1] = gr_complex(1, 0);
+	d_rotational_symmetry = 2;
+	d_dimensionality = 1;
+	calc_arity();
+}
+
+constellation_bpsk_impl::~constellation_bpsk_impl() {
+}
+
+unsigned int
+constellation_bpsk_impl::decision_maker(const gr_complex *sample) {
+	return (real(*sample) > 0);
+}
+
+
+/**********************************************************/
+
+constellation_qpsk::sptr
+constellation_qpsk::make() {
+	return constellation_qpsk::sptr(new constellation_qpsk_impl());
+}
+
+constellation_qpsk::constellation_qpsk() {}
+
+constellation_qpsk_impl::constellation_qpsk_impl() {
+	const float level = sqrt(float(0.5));
+	d_constellation.resize(4);
+	// Gray-coded
+	d_constellation[0] = gr_complex(-level, -level);
+	d_constellation[1] = gr_complex( level, -level);
+	d_constellation[2] = gr_complex(-level,  level);
+	d_constellation[3] = gr_complex( level,  level);
+
+	d_rotational_symmetry = 4;
+	d_dimensionality = 1;
+	calc_arity();
+}
+
+constellation_qpsk_impl::~constellation_qpsk_impl() {
+}
+
+unsigned int
+constellation_qpsk_impl::decision_maker(const gr_complex *sample) {
+	return 2*(imag(*sample)>0) + (real(*sample)>0);
+}
+
+
+/**********************************************************/
+
+constellation_16qam::sptr
+constellation_16qam::make() {
+	return constellation_16qam::sptr(new constellation_16qam_impl());
+}
+
+constellation_16qam::constellation_16qam() {}
+
+constellation_16qam_impl::constellation_16qam_impl()
+{
+	const float level = sqrt(float(0.1));
+	d_constellation.resize(16);
+
+	d_constellation[ 0] = gr_complex(-3*level,-3*level);
+	d_constellation[ 1] = gr_complex( 3*level,-3*level);
+	d_constellation[ 2] = gr_complex(-1*level,-3*level);
+	d_constellation[ 3] = gr_complex( 1*level,-3*level);
+	d_constellation[ 4] = gr_complex(-3*level, 3*level);
+	d_constellation[ 5] = gr_complex( 3*level, 3*level);
+	d_constellation[ 6] = gr_complex(-1*level, 3*level);
+	d_constellation[ 7] = gr_complex( 1*level, 3*level);
+	d_constellation[ 8] = gr_complex(-3*level,-1*level);
+	d_constellation[ 9] = gr_complex( 3*level,-1*level);
+	d_constellation[10] = gr_complex(-1*level,-1*level);
+	d_constellation[11] = gr_complex( 1*level,-1*level);
+	d_constellation[12] = gr_complex(-3*level, 1*level);
+	d_constellation[13] = gr_complex( 3*level, 1*level);
+	d_constellation[14] = gr_complex(-1*level, 1*level);
+	d_constellation[15] = gr_complex( 1*level, 1*level);
+
+	d_rotational_symmetry = 4;
+	d_dimensionality = 1;
+	calc_arity();
+}
+
+constellation_16qam_impl::~constellation_16qam_impl() {
+}
+
+unsigned int
+constellation_16qam_impl::decision_maker(const gr_complex *sample)
+{
+	unsigned int ret = 0;
+	const float level = sqrt(float(0.1));
+	float re = sample->real();
+	float im = sample->imag();
+
+	ret |= re > 0;
+	ret |= (std::abs(re) < (2*level)) << 1;
+	ret |= (im > 0) << 2;
+	ret |= (std::abs(im) < (2*level)) << 3;
+
+	return ret;
+}
+
+
+/**********************************************************/
+
+constellation_64qam::sptr
+constellation_64qam::make() {
+	return constellation_64qam::sptr(new constellation_64qam_impl());
+}
+
+constellation_64qam::constellation_64qam() {}
+
+constellation_64qam_impl::constellation_64qam_impl() {
+	const float level = sqrt(float(1/42.0));
+	d_constellation.resize(64);
+
+	d_constellation[ 0] = gr_complex(-7*level,-7*level);
+	d_constellation[ 1] = gr_complex( 7*level,-7*level);
+	d_constellation[ 2] = gr_complex(-1*level,-7*level);
+	d_constellation[ 3] = gr_complex( 1*level,-7*level);
+	d_constellation[ 4] = gr_complex(-5*level,-7*level);
+	d_constellation[ 5] = gr_complex( 5*level,-7*level);
+	d_constellation[ 6] = gr_complex(-3*level,-7*level);
+	d_constellation[ 7] = gr_complex( 3*level,-7*level);
+	d_constellation[ 8] = gr_complex(-7*level, 7*level);
+	d_constellation[ 9] = gr_complex( 7*level, 7*level);
+	d_constellation[10] = gr_complex(-1*level, 7*level);
+	d_constellation[11] = gr_complex( 1*level, 7*level);
+	d_constellation[12] = gr_complex(-5*level, 7*level);
+	d_constellation[13] = gr_complex( 5*level, 7*level);
+	d_constellation[14] = gr_complex(-3*level, 7*level);
+	d_constellation[15] = gr_complex( 3*level, 7*level);
+	d_constellation[16] = gr_complex(-7*level,-1*level);
+	d_constellation[17] = gr_complex( 7*level,-1*level);
+	d_constellation[18] = gr_complex(-1*level,-1*level);
+	d_constellation[19] = gr_complex( 1*level,-1*level);
+	d_constellation[20] = gr_complex(-5*level,-1*level);
+	d_constellation[21] = gr_complex( 5*level,-1*level);
+	d_constellation[22] = gr_complex(-3*level,-1*level);
+	d_constellation[23] = gr_complex( 3*level,-1*level);
+	d_constellation[24] = gr_complex(-7*level, 1*level);
+	d_constellation[25] = gr_complex( 7*level, 1*level);
+	d_constellation[26] = gr_complex(-1*level, 1*level);
+	d_constellation[27] = gr_complex( 1*level, 1*level);
+	d_constellation[28] = gr_complex(-5*level, 1*level);
+	d_constellation[29] = gr_complex( 5*level, 1*level);
+	d_constellation[30] = gr_complex(-3*level, 1*level);
+	d_constellation[31] = gr_complex( 3*level, 1*level);
+	d_constellation[32] = gr_complex(-7*level,-5*level);
+	d_constellation[33] = gr_complex( 7*level,-5*level);
+	d_constellation[34] = gr_complex(-1*level,-5*level);
+	d_constellation[35] = gr_complex( 1*level,-5*level);
+	d_constellation[36] = gr_complex(-5*level,-5*level);
+	d_constellation[37] = gr_complex( 5*level,-5*level);
+	d_constellation[38] = gr_complex(-3*level,-5*level);
+	d_constellation[39] = gr_complex( 3*level,-5*level);
+	d_constellation[40] = gr_complex(-7*level, 5*level);
+	d_constellation[41] = gr_complex( 7*level, 5*level);
+	d_constellation[42] = gr_complex(-1*level, 5*level);
+	d_constellation[43] = gr_complex( 1*level, 5*level);
+	d_constellation[44] = gr_complex(-5*level, 5*level);
+	d_constellation[45] = gr_complex( 5*level, 5*level);
+	d_constellation[46] = gr_complex(-3*level, 5*level);
+	d_constellation[47] = gr_complex( 3*level, 5*level);
+	d_constellation[48] = gr_complex(-7*level,-3*level);
+	d_constellation[49] = gr_complex( 7*level,-3*level);
+	d_constellation[50] = gr_complex(-1*level,-3*level);
+	d_constellation[51] = gr_complex( 1*level,-3*level);
+	d_constellation[52] = gr_complex(-5*level,-3*level);
+	d_constellation[53] = gr_complex( 5*level,-3*level);
+	d_constellation[54] = gr_complex(-3*level,-3*level);
+	d_constellation[55] = gr_complex( 3*level,-3*level);
+	d_constellation[56] = gr_complex(-7*level, 3*level);
+	d_constellation[57] = gr_complex( 7*level, 3*level);
+	d_constellation[58] = gr_complex(-1*level, 3*level);
+	d_constellation[59] = gr_complex( 1*level, 3*level);
+	d_constellation[60] = gr_complex(-5*level, 3*level);
+	d_constellation[61] = gr_complex( 5*level, 3*level);
+	d_constellation[62] = gr_complex(-3*level, 3*level);
+	d_constellation[63] = gr_complex( 3*level, 3*level);
+
+	d_rotational_symmetry = 4;
+	d_dimensionality = 1;
+	calc_arity();
+}
+
+constellation_64qam_impl::~constellation_64qam_impl() {
+}
+
+unsigned int
+constellation_64qam_impl::decision_maker(const gr_complex *sample) {
+	unsigned int ret = 0;
+	const float level = sqrt(float(1/42.0));
+	float re = sample->real();
+	float im = sample->imag();
+
+	ret |= re > 0;
+	ret |= (std::abs(re) < (4*level)) << 1;
+	ret |= (std::abs(re) < (6*level) && std::abs(re) > (2*level)) << 2;
+	ret |= (im > 0) << 3;
+	ret |= (std::abs(im) < (4*level)) << 4;
+	ret |= (std::abs(im) < (6*level) && std::abs(im) > (2*level)) << 5;
+
+	return ret;
+}
diff --git a/lib/constellations_impl.h b/lib/constellations_impl.h
new file mode 100644
index 0000000..7519d0b
--- /dev/null
+++ b/lib/constellations_impl.h
@@ -0,0 +1,71 @@
+/*
+ * Copyright (C) 2016 Bastian Bloessl <bloessl@ccs-labs.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/>.
+ */
+#ifndef INCLUDED_IEEE802_11_CONSTELLATIONS_IMPL_H
+#define INCLUDED_IEEE802_11_CONSTELLATIONS_IMPL_H
+
+#include <ieee802-11/constellations.h>
+
+namespace gr {
+namespace ieee802_11 {
+
+class constellation_bpsk_impl : public constellation_bpsk
+{
+public:
+	constellation_bpsk_impl();
+	~constellation_bpsk_impl();
+
+	unsigned int decision_maker(const gr_complex *sample);
+};
+
+
+class constellation_qpsk_impl : public constellation_qpsk
+{
+public:
+	constellation_qpsk_impl();
+	~constellation_qpsk_impl();
+
+	unsigned int decision_maker(const gr_complex *sample);
+};
+
+
+
+class constellation_16qam_impl : public constellation_16qam
+{
+public:
+	constellation_16qam_impl();
+	~constellation_16qam_impl();
+
+	unsigned int decision_maker(const gr_complex *sample);
+};
+
+
+
+
+class constellation_64qam_impl : public constellation_64qam
+{
+public:
+	constellation_64qam_impl();
+	~constellation_64qam_impl();
+
+	unsigned int decision_maker(const gr_complex *sample);
+};
+
+
+} // namespace ieee802_11
+} // namespace gr
+
+#endif /* INCLUDED_IEEE802_11_CONSTELLATIONS_IMPL_H */
diff --git a/swig/ieee802_11_swig.i b/swig/ieee802_11_swig.i
index 2995854..2eba124 100644
--- a/swig/ieee802_11_swig.i
+++ b/swig/ieee802_11_swig.i
@@ -25,6 +25,7 @@
 #include "gnuradio/digital/packet_header_default.h"
 
 #include "ieee802-11/chunks_to_symbols.h"
+#include "ieee802-11/constellations.h"
 #include "ieee802-11/ether_encap.h"
 #include "ieee802-11/moving_average_cc.h"
 #include "ieee802-11/moving_average_ff.h"
@@ -41,7 +42,13 @@
 
 %include "gnuradio/digital/packet_header_default.h"
 
+%ignore gr::digital::constellation_bpsk;
+%ignore gr::digital::constellation_qpsk;
+%ignore gr::digital::constellation_16qam;
+%include "gnuradio/digital/constellation.h"
+
 %include "ieee802-11/chunks_to_symbols.h"
+%include "ieee802-11/constellations.h"
 %include "ieee802-11/ether_encap.h"
 %include "ieee802-11/moving_average_cc.h"
 %include "ieee802-11/moving_average_ff.h"
@@ -71,5 +78,29 @@ GR_SWIG_BLOCK_MAGIC2(ieee802_11, sync_short);
 %template(signal_field_sptr) boost::shared_ptr<gr::ieee802_11::signal_field>;
 %pythoncode %{
 signal_field_sptr.__repr__ = lambda self: "<signal_field>"
-signal_field = signal_field .make;
+signal_field = signal_field.make;
+%}
+
+%template(constellation_bpsk_sptr) boost::shared_ptr<gr::ieee802_11::constellation_bpsk>;
+%pythoncode %{
+constellation_bpsk_sptr.__repr__ = lambda self: "<constellation BPSK>"
+constellation_bpsk = constellation_bpsk.make;
+%}
+
+%template(constellation_qpsk_sptr) boost::shared_ptr<gr::ieee802_11::constellation_qpsk>;
+%pythoncode %{
+constellation_qpsk_sptr.__repr__ = lambda self: "<constellation QPSK>"
+constellation_qpsk = constellation_qpsk.make;
+%}
+
+%template(constellation_16qam_sptr) boost::shared_ptr<gr::ieee802_11::constellation_16qam>;
+%pythoncode %{
+constellation_16qam_sptr.__repr__ = lambda self: "<constellation 16QAM>"
+constellation_16qam = constellation_16qam.make;
+%}
+
+%template(constellation_64qam_sptr) boost::shared_ptr<gr::ieee802_11::constellation_64qam>;
+%pythoncode %{
+constellation_64qam_sptr.__repr__ = lambda self: "<constellation 64QAM>"
+constellation_64qam = constellation_64qam.make;
 %}
diff --git a/utils/16-qam.png b/utils/16-qam.png
new file mode 100644
index 0000000..ad62b30
Binary files /dev/null and b/utils/16-qam.png differ
diff --git a/utils/64-qam.png b/utils/64-qam.png
new file mode 100644
index 0000000..2b7a12a
Binary files /dev/null and b/utils/64-qam.png differ
diff --git a/utils/constellations.py b/utils/constellations.py
new file mode 100644
index 0000000..422fae8
--- /dev/null
+++ b/utils/constellations.py
@@ -0,0 +1,96 @@
+#!/usr/bin/env python
+
+import sys
+import numpy as np
+import matplotlib as mpl
+import matplotlib.pyplot as plt
+
+import ieee802_11
+
+###############################################
+#                 16-QAM
+###############################################
+
+c = ieee802_11.constellation_16qam()
+a = np.array(c.points())
+p = np.average(np.abs(a)**2)
+level = .1**.5
+
+print "16-QAM, average power: {0:.4f}".format(p)
+
+plt.scatter(a.real, a.imag)
+for i, x in enumerate(a):
+    s = "{0:04b}".format(i)[::-1]
+    plt.text(x.real, x.imag+0.1, s, ha='center')
+
+plt.show()
+
+#######################
+# test decison maker
+#######################
+
+N = 1000
+data = np.random.randint(0, 16, N)
+orig_const = a[data]
+noisy_const = orig_const + np.random.sample(N) * 2 * level - level +\
+                           np.random.sample(N) * 2j * level - level * 1j
+
+rx = np.array(map(lambda x: c.decision_maker_v([x]), noisy_const))
+rx_const = a[rx]
+
+if any(rx != data):
+    print "16-QAM: data does not match."
+else:
+    print "16-QAM: points decoded successfully."
+
+plt.scatter(a.real, a.imag)
+plt.scatter(noisy_const.real, noisy_const.imag, marker='x')
+for d, a, b in zip(rx, rx_const, noisy_const):
+    plt.plot([a.real, b.real], [a.imag, b.imag], color=mpl.cm.hsv(d/16.0))
+
+plt.show()
+
+
+
+###############################################
+#                 64-QAM
+###############################################
+
+c = ieee802_11.constellation_64qam()
+a = np.array(c.points())
+p = np.average(np.abs(a)**2)
+level = (1.0/42)**.5
+
+print "64-QAM, average power: {0:.4f}".format(p)
+
+plt.scatter(a.real, a.imag)
+for i, x in enumerate(a):
+    s = "{0:06b}".format(i)[::-1]
+    plt.text(x.real, x.imag+0.06, s, ha='center')
+
+plt.show()
+
+#######################
+# test decison maker
+#######################
+
+N = 1000
+data = np.random.randint(0, 64, N)
+orig_const = a[data]
+noisy_const = orig_const + np.random.sample(N) * 2 * level - level +\
+                           np.random.sample(N) * 2j * level - level * 1j
+
+rx = np.array(map(lambda x: c.decision_maker_v([x]), noisy_const))
+rx_const = a[rx]
+
+if any(rx != data):
+    print "16-QAM: data does not match."
+else:
+    print "16-QAM: points decoded successfully."
+
+plt.scatter(a.real, a.imag)
+plt.scatter(noisy_const.real, noisy_const.imag, marker='x')
+for d, a, b in zip(rx, rx_const, noisy_const):
+    plt.plot([a.real, b.real], [a.imag, b.imag], color=mpl.cm.hsv(d/64.0))
+
+plt.show()