mirror of
https://github.com/JvanKatwijk/dabradio
synced 2025-10-06 00:02:49 +02:00
stupid error in rtlsdr handler
This commit is contained in:
jan van Katwijk
@@ -68,7 +68,7 @@ int32_t i;
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this -> nrBlocks = params. get_L ();
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this -> carriers = params. get_carriers ();
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this -> carrierDiff = params. get_carrierDiff ();
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this -> giveSignal = false;
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this -> scanMode = false;
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ofdmBuffer. resize (2 * T_s);
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ofdmBufferIndex = 0;
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@@ -92,9 +92,10 @@ int32_t i;
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}
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}
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void dabProcessor::start (int frequency, bool giveSignal) {
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this -> frequency = frequency;
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this -> giveSignal = giveSignal;
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void dabProcessor::start (int frequency, bool scanMode) {
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this -> frequency = frequency;
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this -> scanMode = scanMode;
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startFailures = 0;
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this -> QThread::start ();
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}
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@@ -137,7 +138,7 @@ notSynced:
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break; // yes, we are ready
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case NO_DIP_FOUND:
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if (giveSignal && (++ attempts >= 5)) {
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if (scanMode && (++ attempts >= 5)) {
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emit (No_Signal_Found ());
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attempts = 0;
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}
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@@ -174,9 +175,15 @@ SyncOnPhase:
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if (!correctionNeeded) {
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setSyncLost ();
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}
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startFailures ++;
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if (scanMode && (startFailures > 3)) {
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emit (No_Signal_Found ());
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startFailures = 0;
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}
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goto notSynced;
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}
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startFailures = 0;
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/**
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* Once here, we are synchronized, we need to copy the data we
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* used for synchronization for block 0
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@@ -252,6 +259,21 @@ NewOffset:
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*/
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myReader. getSamples (ofdmBuffer. data (),
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T_null, coarseOffset);
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float sum = 0;
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for (i = 0; i < T_null; i ++)
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sum += abs (ofdmBuffer [i]);
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sum /= T_null;
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static float snr = 0;
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snr = 0.9 * snr +
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0.1 * 20 * log10 ((myReader. get_sLevel () + 0.005) / sum);
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static int ccc = 0;
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if (++ccc > 10) {
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ccc = 0;
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show_snr ((int)snr);
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}
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/**
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* The first sample to be found for the next frame should be T_g
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* samples ahead. Before going for the next frame, we
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@@ -4,19 +4,19 @@
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* Jan van Katwijk (J.vanKatwijk@gmail.com)
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* Lazy Chair Computing
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*
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* This file is part of the Qt-DAB program
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* Qt-DAB is free software; you can redistribute it and/or modify
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* This file is part of the dabradio
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* dabradio is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* Qt-DAB is distributed in the hope that it will be useful,
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* dabradio is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with Qt-DAB; if not, write to the Free Software
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* along with dabradio; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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#
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@@ -92,7 +92,8 @@ private:
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mscHandler my_mscHandler;
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int32_t frequency;
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int16_t attempts;
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bool giveSignal;
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bool scanMode;
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int startFailures;
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int32_t T_null;
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int32_t T_u;
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int32_t T_s;
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@@ -112,7 +113,6 @@ private:
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uint32_t ofdmSymbolCount;
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phaseReference phaseSynchronizer;
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ofdmDecoder my_ofdmDecoder;
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bool wasSecond (int16_t, dabParams *);
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virtual void run (void);
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bool isReset;
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signals:
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@@ -120,8 +120,8 @@ signals:
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void No_Signal_Found (void);
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void setSyncLost (void);
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void showCoordinates (int, int);
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// void showCoordinates (float, float);
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void show_Spectrum (int);
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void show_snr (int);
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};
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#endif
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@@ -167,12 +167,12 @@ int i, k;
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gains = new int [gainsCount];
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gainsCount = rtlsdr_get_tuner_gains (device, gains);
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for (i = gainsCount; i > 0; i--) {
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fprintf(stderr, "%.1f ", gains [i - 1] / 10.0);
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fprintf (stderr, "%.1f ", gains [i - 1] / 10.0);
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}
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fprintf(stderr, "\n");
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rtlsdr_set_tuner_gain_mode (device, 1);
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rtlsdr_set_agc_mode (device, 0);
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_I_Buffer = new RingBuffer<uint8_t>(8 * 1024 * 1024);
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//
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// See what the saved values are and restore the GUI settings
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@@ -212,7 +212,8 @@ int i, k;
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#endif
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return;
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}
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//
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// library was open
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stopReader ();
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this -> rtlsdr_close (device);
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@@ -233,7 +234,7 @@ int i, k;
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}
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//
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//
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bool rtlsdrHandler::restartReader (void) {
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bool rtlsdrHandler::restartReader (int32_t frequency) {
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int32_t r;
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if (workerHandle != NULL)
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@@ -244,7 +245,7 @@ int32_t r;
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if (r < 0)
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return false;
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this -> rtlsdr_set_center_freq (device, lastFrequency);
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this -> rtlsdr_set_center_freq (device, frequency);
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workerHandle = new dll_driver (this);
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rtlsdr_set_agc_mode (device, agcControl -> isChecked ());
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rtlsdr_set_tuner_gain (device,
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@@ -268,8 +269,10 @@ void rtlsdrHandler::stopReader (void) {
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//
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// when selecting the gain from a table, use the table value
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void rtlsdrHandler::set_ifgain (int gain) {
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fprintf (stderr, "gain will be set %d to %d\n",
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gain, gains [gain * gainsCount / 100]);
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rtlsdr_set_tuner_gain (device,
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gain * gainsCount / 100);
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gains [gain * gainsCount / 100]);
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}
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//
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void rtlsdrHandler::set_agcControl (int dummy) {
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@@ -277,21 +280,42 @@ void rtlsdrHandler::set_agcControl (int dummy) {
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rtlsdr_set_tuner_gain (device,
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gains [(int)(ifgainSelector -> value () * gainsCount / 100)]);
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}
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//
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// we only have 8 bits, so rather than doing a float division to get
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// the float value we want, we precompute the possibilities
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static
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float convTable [] = {
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-128 / 128.0 , -127 / 128.0 , -126 / 128.0 , -125 / 128.0 , -124 / 128.0 , -123 / 128.0 , -122 / 128.0 , -121 / 128.0 , -120 / 128.0 , -119 / 128.0 , -118 / 128.0 , -117 / 128.0 , -116 / 128.0 , -115 / 128.0 , -114 / 128.0 , -113 / 128.0
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, -112 / 128.0 , -111 / 128.0 , -110 / 128.0 , -109 / 128.0 , -108 / 128.0 , -107 / 128.0 , -106 / 128.0 , -105 / 128.0 , -104 / 128.0 , -103 / 128.0 , -102 / 128.0 , -101 / 128.0 , -100 / 128.0 , -99 / 128.0 , -98 / 128.0 , -97 / 128.0
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, -96 / 128.0 , -95 / 128.0 , -94 / 128.0 , -93 / 128.0 , -92 / 128.0 , -91 / 128.0 , -90 / 128.0 , -89 / 128.0 , -88 / 128.0 , -87 / 128.0 , -86 / 128.0 , -85 / 128.0 , -84 / 128.0 , -83 / 128.0 , -82 / 128.0 , -81 / 128.0
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, -80 / 128.0 , -79 / 128.0 , -78 / 128.0 , -77 / 128.0 , -76 / 128.0 , -75 / 128.0 , -74 / 128.0 , -73 / 128.0 , -72 / 128.0 , -71 / 128.0 , -70 / 128.0 , -69 / 128.0 , -68 / 128.0 , -67 / 128.0 , -66 / 128.0 , -65 / 128.0
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, -64 / 128.0 , -63 / 128.0 , -62 / 128.0 , -61 / 128.0 , -60 / 128.0 , -59 / 128.0 , -58 / 128.0 , -57 / 128.0 , -56 / 128.0 , -55 / 128.0 , -54 / 128.0 , -53 / 128.0 , -52 / 128.0 , -51 / 128.0 , -50 / 128.0 , -49 / 128.0
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, -48 / 128.0 , -47 / 128.0 , -46 / 128.0 , -45 / 128.0 , -44 / 128.0 , -43 / 128.0 , -42 / 128.0 , -41 / 128.0 , -40 / 128.0 , -39 / 128.0 , -38 / 128.0 , -37 / 128.0 , -36 / 128.0 , -35 / 128.0 , -34 / 128.0 , -33 / 128.0
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, -32 / 128.0 , -31 / 128.0 , -30 / 128.0 , -29 / 128.0 , -28 / 128.0 , -27 / 128.0 , -26 / 128.0 , -25 / 128.0 , -24 / 128.0 , -23 / 128.0 , -22 / 128.0 , -21 / 128.0 , -20 / 128.0 , -19 / 128.0 , -18 / 128.0 , -17 / 128.0
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, -16 / 128.0 , -15 / 128.0 , -14 / 128.0 , -13 / 128.0 , -12 / 128.0 , -11 / 128.0 , -10 / 128.0 , -9 / 128.0 , -8 / 128.0 , -7 / 128.0 , -6 / 128.0 , -5 / 128.0 , -4 / 128.0 , -3 / 128.0 , -2 / 128.0 , -1 / 128.0
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, 0 / 128.0 , 1 / 128.0 , 2 / 128.0 , 3 / 128.0 , 4 / 128.0 , 5 / 128.0 , 6 / 128.0 , 7 / 128.0 , 8 / 128.0 , 9 / 128.0 , 10 / 128.0 , 11 / 128.0 , 12 / 128.0 , 13 / 128.0 , 14 / 128.0 , 15 / 128.0
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, 16 / 128.0 , 17 / 128.0 , 18 / 128.0 , 19 / 128.0 , 20 / 128.0 , 21 / 128.0 , 22 / 128.0 , 23 / 128.0 , 24 / 128.0 , 25 / 128.0 , 26 / 128.0 , 27 / 128.0 , 28 / 128.0 , 29 / 128.0 , 30 / 128.0 , 31 / 128.0
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, 32 / 128.0 , 33 / 128.0 , 34 / 128.0 , 35 / 128.0 , 36 / 128.0 , 37 / 128.0 , 38 / 128.0 , 39 / 128.0 , 40 / 128.0 , 41 / 128.0 , 42 / 128.0 , 43 / 128.0 , 44 / 128.0 , 45 / 128.0 , 46 / 128.0 , 47 / 128.0
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, 48 / 128.0 , 49 / 128.0 , 50 / 128.0 , 51 / 128.0 , 52 / 128.0 , 53 / 128.0 , 54 / 128.0 , 55 / 128.0 , 56 / 128.0 , 57 / 128.0 , 58 / 128.0 , 59 / 128.0 , 60 / 128.0 , 61 / 128.0 , 62 / 128.0 , 63 / 128.0
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, 64 / 128.0 , 65 / 128.0 , 66 / 128.0 , 67 / 128.0 , 68 / 128.0 , 69 / 128.0 , 70 / 128.0 , 71 / 128.0 , 72 / 128.0 , 73 / 128.0 , 74 / 128.0 , 75 / 128.0 , 76 / 128.0 , 77 / 128.0 , 78 / 128.0 , 79 / 128.0
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, 80 / 128.0 , 81 / 128.0 , 82 / 128.0 , 83 / 128.0 , 84 / 128.0 , 85 / 128.0 , 86 / 128.0 , 87 / 128.0 , 88 / 128.0 , 89 / 128.0 , 90 / 128.0 , 91 / 128.0 , 92 / 128.0 , 93 / 128.0 , 94 / 128.0 , 95 / 128.0
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, 96 / 128.0 , 97 / 128.0 , 98 / 128.0 , 99 / 128.0 , 100 / 128.0 , 101 / 128.0 , 102 / 128.0 , 103 / 128.0 , 104 / 128.0 , 105 / 128.0 , 106 / 128.0 , 107 / 128.0 , 108 / 128.0 , 109 / 128.0 , 110 / 128.0 , 111 / 128.0
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, 112 / 128.0 , 113 / 128.0 , 114 / 128.0 , 115 / 128.0 , 116 / 128.0 , 117 / 128.0 , 118 / 128.0 , 119 / 128.0 , 120 / 128.0 , 121 / 128.0 , 122 / 128.0 , 123 / 128.0 , 124 / 128.0 , 125 / 128.0 , 126 / 128.0 , 127 / 128.0 };
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//
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// The brave old getSamples. For the dab stick, we get
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// size samples: still in I/Q pairs, but we have to convert the data from
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// uint8_t to std::complex<float> *
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// uint8_t to DSPCOMPLEX *
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int32_t rtlsdrHandler::getSamples (std::complex<float> *V, int32_t size) {
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int32_t amount, i;
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uint8_t *tempBuffer = (uint8_t *)alloca (2 * size * sizeof (uint8_t));
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//
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amount = _I_Buffer -> getDataFromBuffer (tempBuffer, 2 * size);
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for (i = 0; i < amount / 2; i ++)
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V [i] = std::complex<float>
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((float (tempBuffer [2 * i] - 128)) / 128.0,
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(float (tempBuffer [2 * i + 1] - 128)) / 128.0);
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(convTable [tempBuffer [2 * i]],
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convTable [tempBuffer [2 * i + 1]]);;
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return amount / 2;
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}
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@@ -72,7 +72,7 @@ public:
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QCheckBox *);
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~rtlsdrHandler (void);
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// interface to the reader
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bool restartReader (void);
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bool restartReader (int32_t frequency);
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void stopReader (void);
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int32_t getSamples (std::complex<float> *, int32_t);
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int32_t Samples (void);
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@@ -433,6 +433,25 @@
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<string>agc</string>
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</property>
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</widget>
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<widget class="QLCDNumber" name="snrDisplay">
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<property name="geometry">
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<rect>
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<x>300</x>
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<y>30</y>
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<width>64</width>
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<height>23</height>
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</rect>
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</property>
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<property name="frameShape">
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<enum>QFrame::NoFrame</enum>
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</property>
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<property name="digitCount">
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<number>3</number>
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</property>
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<property name="segmentStyle">
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<enum>QLCDNumber::Flat</enum>
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</property>
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</widget>
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</widget>
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<widget class="QStatusBar" name="statusbar"/>
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</widget>
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@@ -4,19 +4,19 @@
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* Jan van Katwijk (J.vanKatwijk@gmail.com)
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* Lazy Chair Computing
|
||||
*
|
||||
* This file is part of the Qt-DAB program
|
||||
* Qt-DAB is free software; you can redistribute it and/or modify
|
||||
* This file is part of the dabradio
|
||||
* dabradio 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 2 of the License, or
|
||||
* (at your option) any later version.
|
||||
*
|
||||
* Qt-DAB is distributed in the hope that it will be useful,
|
||||
* dabradio 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 Qt-DAB; if not, write to the Free Software
|
||||
* along with dabradio; if not, write to the Free Software
|
||||
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
||||
*/
|
||||
#ifndef __OFDM_DECODER__
|
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@@ -55,7 +55,6 @@ public:
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void decode (std::vector<std::complex<float> >,
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int32_t n, int16_t *);
|
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|
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int16_t get_snr (std::complex<float> *);
|
||||
void stop (void);
|
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void reset (void);
|
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private:
|
||||
@@ -71,17 +70,13 @@ private:
|
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int32_t T_g;
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||||
int32_t nrBlocks;
|
||||
int32_t carriers;
|
||||
int16_t getMiddle (void);
|
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std::vector<complex<float>> phaseReference;
|
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std::vector<int16_t> ibits;
|
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std::complex<float> *fft_buffer;
|
||||
phaseTable *phasetable;
|
||||
int32_t blockIndex;
|
||||
int16_t snrCount;
|
||||
int16_t snr;
|
||||
int16_t maxSignal;
|
||||
signals:
|
||||
void show_snr (int);
|
||||
void showIQ (int);
|
||||
void showQuality (float);
|
||||
|
||||
|
||||
12
radio.cpp
12
radio.cpp
@@ -177,6 +177,8 @@ QString h;
|
||||
picturesPath);
|
||||
connect (my_dabProcessor, SIGNAL (setSynced (char)),
|
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this, SLOT (setSynced (char)));
|
||||
connect (my_dabProcessor, SIGNAL (show_snr (int)),
|
||||
this, SLOT (show_snr (int)));
|
||||
//
|
||||
serviceCharacteristics = NULL;
|
||||
secondsTimer. setInterval (1000);
|
||||
@@ -290,6 +292,7 @@ void RadioInterface::nextChannel (void) {
|
||||
|
||||
void RadioInterface::reset (void) {
|
||||
my_dabProcessor -> stop ();
|
||||
|
||||
disconnect (ensembleDisplay,
|
||||
SIGNAL (clicked (QModelIndex)),
|
||||
this, SLOT (selectService (QModelIndex)));
|
||||
@@ -445,7 +448,7 @@ void RadioInterface::showQuality (float f) {
|
||||
}
|
||||
|
||||
void RadioInterface::show_snr (int s) {
|
||||
(void)s;
|
||||
snrDisplay -> display (s);
|
||||
}
|
||||
|
||||
void RadioInterface::set_CorrectorDisplay (int c) {
|
||||
@@ -590,15 +593,16 @@ void RadioInterface::TerminateProcess (void) {
|
||||
displayTimer. stop ();
|
||||
signalTimer. stop ();
|
||||
|
||||
inputDevice -> stopReader ();
|
||||
my_dabProcessor -> stop (); // definitely concurrent
|
||||
soundOut -> stop ();
|
||||
// everything should be halted by now
|
||||
delete soundOut;
|
||||
if (inputDevice != NULL)
|
||||
delete inputDevice;
|
||||
fprintf (stderr, "going to delete dabProcessor\n");
|
||||
delete my_dabProcessor;
|
||||
fprintf (stderr, "deleted dabProcessor\n");
|
||||
delete soundOut;
|
||||
if (inputDevice != NULL)
|
||||
delete inputDevice;
|
||||
if (ensembleDisplay != NULL)
|
||||
delete ensembleDisplay;
|
||||
if (serviceDescription != NULL)
|
||||
|
||||
@@ -4,19 +4,19 @@
|
||||
* Jan van Katwijk (J.vanKatwijk@gmail.com)
|
||||
* Lazy Chair Computing
|
||||
*
|
||||
* This file is part of Qt-DAB
|
||||
* Qt-DAB is free software; you can redistribute it and/or modify
|
||||
* This file is part of dabradio
|
||||
* dabradio 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 2 of the License, or
|
||||
* (at your option) any later version.
|
||||
*
|
||||
* Qt-DAB is distributed in the hope that it will be useful,
|
||||
* dabradio 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 Qt-DAB; if not, write to the Free Software
|
||||
* along with dabradio; if not, write to the Free Software
|
||||
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
||||
*
|
||||
* Once the bits are "in", interpretation and manipulation
|
||||
@@ -68,12 +68,6 @@ int16_t i;
|
||||
this -> T_g = T_s - T_u;
|
||||
fft_buffer = my_fftHandler. getVector ();
|
||||
phaseReference .resize (T_u);
|
||||
|
||||
connect (this, SIGNAL (show_snr (int)),
|
||||
mr, SLOT (show_snr (int)));
|
||||
|
||||
snrCount = 0;
|
||||
snr = 0;
|
||||
}
|
||||
|
||||
ofdmDecoder::~ofdmDecoder (void) {
|
||||
@@ -93,17 +87,6 @@ void ofdmDecoder::processBlock_0 (std::vector <std::complex<float> > buffer) {
|
||||
T_u * sizeof (std::complex<float>));
|
||||
|
||||
my_fftHandler. do_FFT ();
|
||||
/**
|
||||
* The SNR is determined by looking at a segment of bins
|
||||
* within the signal region and bits outside.
|
||||
* It is just an indication
|
||||
*/
|
||||
|
||||
if (++snrCount > 10) {
|
||||
snr = 0.8 * snr + 0.2 * get_snr (fft_buffer);
|
||||
// show_snr (snr);
|
||||
snrCount = 0;
|
||||
}
|
||||
/**
|
||||
* we are now in the frequency domain, and we keep the carriers
|
||||
* as coming from the FFT as phase reference.
|
||||
@@ -205,26 +188,4 @@ toBitsLabel:
|
||||
}
|
||||
}
|
||||
}
|
||||
/**
|
||||
* for the snr we have a full T_u wide vector, with in the middle
|
||||
* K carriers.
|
||||
* Just get the strength from the selected carriers compared
|
||||
* to the strength of the carriers outside that region
|
||||
*/
|
||||
int16_t ofdmDecoder::get_snr (std::complex<float> *v) {
|
||||
int16_t i;
|
||||
float noise = 0;
|
||||
float signal = 0;
|
||||
|
||||
for (i = -100; i < 100; i ++)
|
||||
noise += abs (v [(T_u / 2 + i)]);
|
||||
|
||||
noise /= 200;
|
||||
for (i = - carriers / 4; i < carriers / 4; i ++)
|
||||
signal += abs (v [(T_u + i) % T_u]);
|
||||
signal /= (carriers / 2);
|
||||
|
||||
return 20 * log10 ((signal + 0.005) / (noise + 0.005));
|
||||
}
|
||||
|
||||
|
||||
|
||||
Reference in New Issue
Block a user