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diff --git a/gr-fec/python/fec/polar/channel_construction_bec.py b/gr-fec/python/fec/polar/channel_construction_bec.py
new file mode 100644
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+++ b/gr-fec/python/fec/polar/channel_construction_bec.py
@@ -0,0 +1,110 @@
+#!/usr/bin/env python
+#
+# Copyright 2015 Free Software Foundation, Inc.
+#
+# 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 as np
+import matplotlib.pyplot as plt
+
+def bsc_channel(p):
+    '''
+    binary symmetric channel (BSC)
+    output alphabet Y = {0, 1} and
+    W(0|0) = W(1|1) and W(1|0) = W(0|1)
+
+    this function returns a prob's vector for a BSC
+    p denotes an erroneous transistion
+    '''
+    if not (p >= 0.0 and p <= 1.0):
+        print "given p is out of range!"
+        return np.array([], dtype=float)
+
+    # 0 -> 0, 0 -> 1, 1 -> 0, 1 -> 1
+    W = np.array([[1 - p, p], [p, 1 - p]], dtype=float)
+    return W
+
+
+def bec_channel(eta):
+    '''
+    binary erasure channel (BEC)
+    for each y e Y
+    W(y|0) * W(y|1) = 0 or W(y|0) = W(y|1)
+    transistions are 1 -> 1 or 0 -> 0 or {0, 1} -> ? (erased symbol)
+    '''
+
+    # looks like BSC but should be interpreted differently.
+    W = np.array((1 - eta, eta, 1 - eta), dtype=float)
+    return W
+
+
+def odd_rec(iwn):
+    return iwn ** 2
+
+
+def even_rec(iwn):
+    return 2 * iwn - iwn ** 2
+
+
+def calc_one_recursion(iw0):
+    iw1 = np.zeros(2 * len(iw0))  # double values
+    for i in range(len(iw0)):
+        # careful indices screw you because paper is '1' based :(
+        iw1[2 * i] = odd_rec(iw0[i])
+        iw1[2 * i + 1] = even_rec(iw0[i])
+    return iw1
+
+
+def calculate_bec_channel_capacities(eta, n):
+    iw = 1 - eta  # holds for BEC as stated in paper
+    iw = np.array([iw, ], dtype=float)
+    lw = int(np.log2(n))
+    for i in range(lw):
+        iw = calc_one_recursion(iw)
+    return iw
+
+
+def get_frozen_bit_indices_from_capacities(chan_caps, nfrozen):
+    indexes = np.array([], dtype=int)
+    while indexes.size < nfrozen:
+        index = np.argmin(chan_caps)
+        indexes = np.append(indexes, index)
+        chan_caps[index] = 1.0
+    return np.sort(indexes)
+
+
+def bec_channel_contruction_tests():
+    n = 2 ** 10
+    k = n // 2
+    eta = 0.3
+    bec_capacities = calculate_bec_channel_capacities(eta, n)
+    print(bec_capacities)
+
+    frozenbits_position = get_frozen_bit_indices_from_capacities(bec_capacities, k)
+
+    print('frozenbit_positions:')
+    print(frozenbits_position)
+    print('frozenbit_num:', frozenbits_position.size)
+
+
+def main():
+    print 'channel construction main'
+    bec_channel_contruction_tests()
+
+
+if __name__ == '__main__':
+    main()