From 5e8b4c680934a16b6e554c53ba2bd3ae4f621d49 Mon Sep 17 00:00:00 2001 From: piotr Date: Thu, 4 Jun 2009 13:19:27 +0200 Subject: Revert "removed void detect_norm_burst(const gr_complex * in, gr_complex * chan_imp_resp, int burst_start, unsigned char * output_binary);" This reverts commit 99e4a46c9acfb833ae2c9c198046933f9117dca8. --- src/lib/gsm_receiver_cf.cc | 41 +++++++++++++++++++++++++++++++++++++++++ src/lib/gsm_receiver_cf.h | 2 ++ 2 files changed, 43 insertions(+) (limited to 'src') diff --git a/src/lib/gsm_receiver_cf.cc b/src/lib/gsm_receiver_cf.cc index 8e3bad0..ce59bee 100644 --- a/src/lib/gsm_receiver_cf.cc +++ b/src/lib/gsm_receiver_cf.cc @@ -695,3 +695,44 @@ int gsm_receiver_cf::get_norm_chan_imp_resp(const gr_complex *in, gr_complex * c burst_start = search_start_pos + strongest_window_nr + chan_imp_resp_center - 66 * d_OSR - 2 * d_OSR + 2; return burst_start; } + +void gsm_receiver_cf::detect_norm_burst(const gr_complex * in, gr_complex * chan_imp_resp, int burst_start, unsigned char * output_binary) +{ + float output[BURST_SIZE]; + gr_complex rhh_temp[CHAN_IMP_RESP_LENGTH*d_OSR]; + gr_complex rhh[CHAN_IMP_RESP_LENGTH]; + gr_complex filtered_burst[BURST_SIZE]; + int start_state = 3; + unsigned int stop_states[2] = {4, 12}; + + autocorrelation(chan_imp_resp, rhh_temp, d_chan_imp_length*d_OSR); + for (int ii = 0; ii < (d_chan_imp_length); ii++) { + rhh[ii] = conj(rhh_temp[ii*d_OSR]); + } + + mafi_norm(&in[burst_start], BURST_SIZE, chan_imp_resp, d_chan_imp_length*d_OSR, filtered_burst); + + viterbi_detector(filtered_burst, BURST_SIZE, rhh, start_state, stop_states, 2, output); + + for (int i = 0; i < BURST_SIZE ; i++) { + output_binary[i] = (output[i] > 0); + } +} + +inline void gsm_receiver_cf::mafi_norm(const gr_complex * input, int input_length, gr_complex * filter, int filter_length, gr_complex * output) +{ + int ii = 0, n, a; + + for (n = 0; n < input_length; n++) { + a = n * d_OSR; + output[n] = 0; + ii = 0; + + while (ii < filter_length) { + if ((a + ii) >= input_length*d_OSR) + break; + output[n] += input[a+ii] * filter[ii]; //!!conj + ii++; + } + } +} diff --git a/src/lib/gsm_receiver_cf.h b/src/lib/gsm_receiver_cf.h index cfdcd5b..796bb5b 100644 --- a/src/lib/gsm_receiver_cf.h +++ b/src/lib/gsm_receiver_cf.h @@ -290,6 +290,8 @@ class gsm_receiver_cf : public gr_block inline void autocorrelation(const gr_complex * input, gr_complex * out, int length); inline void mafi(const gr_complex * input, int input_length, gr_complex * filter, int filter_length, gr_complex * output); int get_norm_chan_imp_resp(const gr_complex *in, gr_complex * chan_imp_resp, unsigned search_range); + void detect_norm_burst(const gr_complex * in, gr_complex * chan_imp_resp, int burst_start, unsigned char * output_binary); + inline void mafi_norm(const gr_complex * input, int input_length, gr_complex * filter, int filter_length, gr_complex * output); public: ~gsm_receiver_cf(); -- cgit v1.2.3