diff options
| -rw-r--r-- | gr-digital/include/digital/constellation_receiver_cb.h | 26 |
1 files changed, 3 insertions, 23 deletions
diff --git a/gr-digital/include/digital/constellation_receiver_cb.h b/gr-digital/include/digital/constellation_receiver_cb.h index 0ade7fc217..31138974ef 100644 --- a/gr-digital/include/digital/constellation_receiver_cb.h +++ b/gr-digital/include/digital/constellation_receiver_cb.h @@ -31,36 +31,16 @@ namespace gr { namespace digital { /*! - * \brief This block takes care of receiving generic modulated signals - * through phase, frequency, and symbol synchronization. - * \ingroup modulators_blk + * \brief This block makes hard decisions about the received + * symbols (using a constellation object) and also fine tunes + * phase synchronization. * * \details - * This block takes care of receiving generic modulated signals - * through phase, frequency, and symbol synchronization. It - * performs carrier frequency and phase locking as well as symbol - * timing recovery. * * The phase and frequency synchronization are based on a Costas * loop that finds the error of the incoming signal point compared * to its nearest constellation point. The frequency and phase of * the NCO are updated according to this error. - * - * The symbol synchronization is done using a modified Mueller and - * Muller circuit from the paper: - * - * "G. R. Danesfahani, T.G. Jeans, "Optimisation of modified - * Mueller and Muller algorithm," Electronics Letters, Vol. 31, - * no. 13, 22 June 1995, pp. 1032 - 1033." - * - * This circuit interpolates the downconverted sample (using the - * NCO developed by the Costas loop) every mu samples, then it - * finds the sampling error based on this and the past symbols and - * the decision made on the samples. Like the phase error - * detector, there are optimized decision algorithms for BPSK and - * QPKS, but 8PSK uses another brute force computation against all - * possible symbols. The modifications to the M&M used here reduce - * self-noise. */ class DIGITAL_API constellation_receiver_cb : virtual public gr_block |