diff options
Diffstat (limited to 'gnuradio-core/src/lib/general/gr_constellation.cc')
| -rw-r--r-- | gnuradio-core/src/lib/general/gr_constellation.cc | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/gnuradio-core/src/lib/general/gr_constellation.cc b/gnuradio-core/src/lib/general/gr_constellation.cc index 477532e5c9..403394eaac 100644 --- a/gnuradio-core/src/lib/general/gr_constellation.cc +++ b/gnuradio-core/src/lib/general/gr_constellation.cc @@ -29,6 +29,7 @@ #include <stdlib.h> #define M_TWOPI (2*M_PI) +#define SQRT_TWO 0.707107 gr_constellation_sptr gr_make_constellation(std::vector<gr_complex> constellation) @@ -190,3 +191,27 @@ unsigned int gr_constellation_bpsk::decision_maker(gr_complex sample) { return (real(sample) > 0); } + + +gr_constellation_qpsk_sptr +gr_make_constellation_qpsk() +{ + return gr_constellation_qpsk_sptr(new gr_constellation_qpsk ()); +} + +gr_constellation_qpsk::gr_constellation_qpsk () +{ + d_constellation.resize(4); + // Gray-coded + d_constellation[0] = gr_complex(-SQRT_TWO, -SQRT_TWO); + d_constellation[1] = gr_complex(SQRT_TWO, -SQRT_TWO); + d_constellation[2] = gr_complex(-SQRT_TWO, SQRT_TWO); + d_constellation[3] = gr_complex(SQRT_TWO, SQRT_TWO); +} + +unsigned int gr_constellation_qpsk::decision_maker(gr_complex sample) +{ + // Real component determines small bit. + // Imag component determines big bit. + return 2*(imag(sample)>0) + (real(sample)>0); +} |