diff options
| author | jcorgan <jcorgan@221aa14e-8319-0410-a670-987f0aec2ac5> | 2007-09-18 18:59:00 +0000 |
|---|---|---|
| committer | jcorgan <jcorgan@221aa14e-8319-0410-a670-987f0aec2ac5> | 2007-09-18 18:59:00 +0000 |
| commit | e692e71305ecd71d3681fe37f3d76f350d67e276 (patch) | |
| tree | dc320c9261303aa9a92f4d12bdba85f82720d1bf /gnuradio-core/src/python/gnuradio/blks2impl/qam.py | |
| parent | 6ad04a094ced626e46c210b9847eae46a1ae8e67 (diff) | |
Merge r6461:6464 from jcorgan/t162-staging into trunk.
* Final gr.top_block and gr.hier_block2 implementation inside
gnuradio-core/src/lib/runtime
* Implementation of gr.hier_block2 versions of all the old-style blocks
in blks. These live in blks2.
* Addition of gr.hier_block2 based versions of gr-wxgui blocks
* Conversion of all the example code in gnuradio-examples to use this
new code
* Conversion of all the gr-utils scripts to use the new code
The OFDM examples and related hierarchical blocks have not yet been
converted. Code in the rest of the tree that is outside the core
and example components has also not yet been converted.
git-svn-id: http://gnuradio.org/svn/gnuradio/trunk@6466 221aa14e-8319-0410-a670-987f0aec2ac5
Diffstat (limited to 'gnuradio-core/src/python/gnuradio/blks2impl/qam.py')
| -rw-r--r-- | gnuradio-core/src/python/gnuradio/blks2impl/qam.py | 113 |
1 files changed, 113 insertions, 0 deletions
diff --git a/gnuradio-core/src/python/gnuradio/blks2impl/qam.py b/gnuradio-core/src/python/gnuradio/blks2impl/qam.py new file mode 100644 index 0000000000..22b1e1dabb --- /dev/null +++ b/gnuradio-core/src/python/gnuradio/blks2impl/qam.py @@ -0,0 +1,113 @@ +# +# Copyright 2005,2006 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. +# + +from math import pi, sqrt +import math + +# These constellations are generated for Gray coding when symbos [1, ..., m] are used +# Mapping to Gray coding is therefore unnecessary + +def make_constellation(m): + # number of bits/symbol (log2(M)) + k = int(math.log10(m) / math.log10(2.0)) + + coeff = 1 + const_map = [] + for i in range(m): + a = (i&(0x01 << k-1)) >> k-1 + b = (i&(0x01 << k-2)) >> k-2 + bits_i = [((i&(0x01 << k-j-1)) >> k-j-1) for j in range(2, k, 2)] + bits_q = [((i&(0x01 << k-j-1)) >> k-j-1) for j in range(3, k, 2)] + + ss = 0 + ll = len(bits_i) + for ii in range(ll): + rr = 0 + for jj in range(ll-ii): + rr = abs(bits_i[jj] - rr) + ss += rr*pow(2.0, ii+1) + re = (2*a-1)*(ss+1) + + ss = 0 + ll = len(bits_q) + for ii in range(ll): + rr = 0 + for jj in range(ll-ii): + rr = abs(bits_q[jj] - rr) + ss += rr*pow(2.0, ii+1) + im = (2*b-1)*(ss+1) + + a = max(re, im) + if a > coeff: + coeff = a + const_map.append(complex(re, im)) + + norm_map = [complex(i.real/coeff, i.imag/coeff) for i in const_map] + return norm_map + +# Common definition of constellations for Tx and Rx +constellation = { + 4 : make_constellation(4), # QAM4 (QPSK) + 8 : make_constellation(8), # QAM8 + 16: make_constellation(16), # QAM16 + 64: make_constellation(64), # QAM64 + 256: make_constellation(256) # QAM256 + } + +# ----------------------- +# Do Gray code +# ----------------------- +# binary to gray coding +binary_to_gray = { + 4 : range(4), + 8 : range(8), + 16: range(16), + 64: range(64), + 256: range(256) + } + +# gray to binary +gray_to_binary = { + 4 : range(4), + 8 : range(8), + 16: range(16), + 64: range(64), + 256: range(256) + } + +# ----------------------- +# Don't Gray code +# ----------------------- +# identity mapping +binary_to_ungray = { + 4 : range(4), + 8 : range(8), + 16: range(16), + 64: range(64) + } + +# identity mapping +ungray_to_binary = { + 4 : range(4), + 8 : range(8), + 16: range(16), + 64: range(64) + } |