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diff --git a/gr-digital/python/digital/psk_constellations.py b/gr-digital/python/digital/psk_constellations.py
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+++ b/gr-digital/python/digital/psk_constellations.py
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+#!/usr/bin/env python
+#
+# Copyright 2013 Free Software Foundation, Inc.
+# 
+# This file is part of GNU Radio
+# 
+# GNU Radio 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, or (at your option)
+# any later version.
+# 
+# GNU Radio 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 GNU Radio; see the file COPYING.  If not, write to
+# the Free Software Foundation, Inc., 51 Franklin Street,
+# Boston, MA 02110-1301, USA.
+# 
+
+import numpy
+from constellation_map_generator import *
+
+'''
+Note on the naming scheme. Each constellation is named using a prefix
+for the type of constellation, the order of the constellation, and a
+distinguishing feature, which comes in three modes:
+
+- No extra feature: the basic Gray-coded constellation map; others
+  will be derived from this type.
+- A single number: an indexed number to uniquely identify different
+  constellation maps.
+- 0xN_x0_x1..._xM: A permutation of the base constellation, explained
+  below.
+
+For rectangular constellations (BPSK, QPSK, QAM), we can define a
+hyperspace and look for all symmetries. This is also known as the
+automorphism group of the hypercube, aka the hyperoctahedral
+group. What this means is that we can easily define all possible
+rotations in terms of the first base mapping by creating the mapping:
+
+  f(x) = k XOR pi(x)
+
+The x is the bit string for the symbol we are altering. Then k is a
+bit string of n bits where n is the number of bits per symbol in the
+constellation (e.g., 2 for QPSK or 6 for QAM64). The pi is a
+permutation function specified as pi_0, pi_1..., pi_n-1. This permutes
+the bits from the base constellation symbol to a new code, which is
+then xor'd by k.
+
+The value of k is from 0 to 2^n-1 and pi is a list of all bit
+positions.
+
+The total number of Gray coded modulations is (2^n)*(n!).
+
+We create aliases for all possible naming schemes for the
+constellations. So if a hyperoctahedral group is defined, we also set
+this function equal to a function name using a unique ID number, and
+we always select one rotation as our basic rotation that the other
+rotations are based off of.
+'''
+
+# BPSK Constellation Mappings
+
+def psk_2_0x0():
+    '''
+    0 | 1
+    '''
+    const_points = [-1, 1]
+    symbols = [0, 1]
+    return (const_points, symbols)
+psk_2 = psk_2_0x0  # Basic BPSK rotation
+psk_2_0 = psk_2    # First ID for BPSK rotations
+
+def psk_2_0x1():
+    '''
+    1 | 0
+    '''
+    const_points = [-1, 1]
+    symbols = [1, 0]
+    return (const_points, symbols)
+psk_2_1 = psk_2_0x1
+
+
+############################################################
+# BPSK Soft bit LUT generators
+############################################################
+
+def sd_psk_2_0x0(x, Es=1):
+    '''
+    0 | 1
+    '''
+    x_re = x.real
+    dist = Es*numpy.sqrt(2)
+    return [dist*x_re,]
+sd_psk_2 = sd_psk_2_0x0  # Basic BPSK rotation
+sd_psk_2_0 = sd_psk_2    # First ID for BPSK rotations
+
+def sd_psk_2_0x1(x, Es=1):
+    '''
+    1 | 0
+    '''
+    x_re = [x.real,]
+    dist = Es*numpy.sqrt(2)
+    return -dist*x_re
+sd_psk_2_1 = sd_psk_2_0x1
+
+
+############################################################
+# QPSK Constellation Mappings
+############################################################
+
+def psk_4_0x0_0_1():
+    '''
+    10 | 11
+    -------
+    00 | 01
+    '''
+    const_points = [-1-1j, 1-1j,
+                    -1+1j, 1+1j]
+    symbols = [0, 1, 2, 3]
+    return (const_points, symbols)
+psk_4 = psk_4_0x0_0_1
+psk_4_0 = psk_4
+
+def psk_4_0x1_0_1():
+    '''
+    11 | 10
+    -------
+    01 | 00
+    '''
+    k = 0x1
+    pi = [0, 1]
+    return constellation_map_generator(psk_4, k, pi)
+psk_4_1 = psk_4_0x1_0_1
+
+def psk_4_0x2_0_1():
+    '''
+    00 | 01
+    -------
+    10 | 11
+    '''
+    k = 0x2
+    pi = [0, 1]
+    return constellation_map_generator(psk_4, k, pi)
+psk_4_2 = psk_4_0x2_0_1
+
+def psk_4_0x3_0_1():
+    '''
+    01 | 00
+    -------
+    11 | 10
+    '''
+    k = 0x3
+    pi = [0, 1]
+    return constellation_map_generator(psk_4, k, pi)
+psk_4_3 = psk_4_0x3_0_1
+
+def psk_4_0x0_1_0():
+    '''
+    01 | 11
+    -------
+    00 | 10
+    '''
+    k = 0x0
+    pi = [1, 0]
+    return constellation_map_generator(psk_4, k, pi)
+psk_4_4 = psk_4_0x0_1_0
+
+def psk_4_0x1_1_0():
+    '''
+    00 | 10
+    -------
+    01 | 11
+    '''
+    k = 0x1
+    pi = [1, 0]
+    return constellation_map_generator(psk_4, k, pi)
+psk_4_5 = psk_4_0x1_1_0
+
+def psk_4_0x2_1_0():
+    '''
+    11 | 01
+    -------
+    10 | 00
+    '''
+    k = 0x2
+    pi = [1, 0]
+    return constellation_map_generator(psk_4, k, pi)
+psk_4_6 = psk_4_0x2_1_0
+
+def psk_4_0x3_1_0():
+    '''
+    10 | 00
+    -------
+    11 | 01
+    '''
+    k = 0x3
+    pi = [1, 0]
+    return constellation_map_generator(psk_4, k, pi)
+psk_4_7 = psk_4_0x3_1_0
+
+
+
+############################################################
+# QPSK Constellation Softbit LUT generators
+############################################################
+
+def sd_psk_4_0x0_0_1(x, Es=1):
+    '''
+    10 | 11
+    -------
+    00 | 01
+    '''
+    x_re = x.real
+    x_im = x.imag
+    dist = Es*numpy.sqrt(2)
+    return [dist*x_im, dist*x_re]
+sd_psk_4 = sd_psk_4_0x0_0_1
+sd_psk_4_0 = sd_psk_4
+
+def sd_psk_4_0x1_0_1(x, Es=1):
+    '''
+    11 | 10
+    -------
+    01 | 00
+    '''
+    x_re = x.real
+    x_im = x.imag
+    dist = Es*numpy.sqrt(2)
+    return [dist*x_im, -dist*x_re]
+sd_psk_4_1 = sd_psk_4_0x1_0_1
+
+def sd_psk_4_0x2_0_1(x, Es=1):
+    '''
+    00 | 01
+    -------
+    10 | 11
+    '''
+    x_re = x.real
+    x_im = x.imag
+    dist = Es*numpy.sqrt(2)
+    return [-dist*x_im, dist*x_re]
+sd_psk_4_2 = sd_psk_4_0x2_0_1
+
+def sd_psk_4_0x3_0_1(x, Es=1):
+    '''
+    01 | 00
+    -------
+    11 | 10
+    '''
+    x_re = x.real
+    x_im = x.imag
+    dist = Es*numpy.sqrt(2)
+    return [-dist*x_im, -dist*x_re]
+sd_psk_4_3 = sd_psk_4_0x3_0_1
+
+def sd_psk_4_0x0_1_0(x, Es=1):
+    '''
+    01 | 11
+    -------
+    00 | 10
+    '''
+    x_re = x.real
+    x_im = x.imag
+    dist = Es*numpy.sqrt(2)
+    return [dist*x_re, dist*x_im]
+sd_psk_4_4 = sd_psk_4_0x0_1_0
+
+def sd_psk_4_0x1_1_0(x, Es=1):
+    '''
+    00 | 10
+    -------
+    01 | 11
+    '''
+    x_re = x.real
+    x_im = x.imag
+    dist = Es*numpy.sqrt(2)
+    return [dist*x_re, -dist*x_im]
+sd_psk_4_5 = sd_psk_4_0x1_1_0
+
+
+def sd_psk_4_0x2_1_0(x, Es=1):
+    '''
+    11 | 01
+    -------
+    10 | 00
+    '''
+    x_re = x.real
+    x_im = x.imag
+    dist = Es*numpy.sqrt(2)
+    return [-dist*x_re, dist*x_im]
+sd_psk_4_6 = sd_psk_4_0x2_1_0
+
+def sd_psk_4_0x3_1_0(x, Es=1):
+    '''
+    10 | 00
+    -------
+    11 | 01
+    '''
+    x_re = x.real
+    x_im = x.imag
+    dist = Es*numpy.sqrt(2)
+    return [-dist*x_re, -dist*x_im]
+sd_psk_4_7 = sd_psk_4_0x3_1_0
+