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Improved calculating signal strength and quality (cont'd)

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This commit is contained in:
Klaus Schmidinger 2018-02-15 15:37:01 +01:00
parent a4343bdfd9
commit a1c53eae1e
1 changed files with 25 additions and 6 deletions
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31
dvbdevice.c
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@ -4,7 +4,7 @@
* See the main source file 'vdr.c' for copyright information and
* how to reach the author.
*
* $Id: dvbdevice.c 4.15 2018/02/12 14:05:22 kls Exp $
* $Id: dvbdevice.c 4.16 2018/02/15 15:37:01 kls Exp $
*/
#include "dvbdevice.h"
@ -749,18 +749,37 @@ int StrengthToSSI(const cChannel *Channel, int Strength, int FeModulation, int F
(prel < 35) ? (prel - 20) * 2 / 3 + 90 : // 90% - 100%
100;
#ifdef DEBUG_SIGNALSTRENGTH
fprintf(stderr, "SSI: STR:%d, Pref:%d, Prel:%d, ssi:%d%%(sys:%d, mod:%d, fec:%d)\n", Strength, pref, prel, ssi, dtp.System(), mod, fec);
fprintf(stderr, "SSI-T: STR:%d, Pref:%d, Prel:%d, ssi:%d%%(sys:%d, mod:%d, fec:%d)\n", Strength, pref, prel, ssi, dtp.System(), mod, fec);
#endif
}
}
else if (Channel->IsCable()) { // ! COMPLETELY UNTESTED !
// Formula: pref(dB) = -174.0 + NoiseFigure + SymRef + CnRef
// NoiseFigure = 6.5 dB; -> Tuner specific - range: 3.5 .. 9.0 dB
// SymRef = 10*log(6900000) = 68.5 dB; -> for Symbolrate of 6900 kSym/sec (TV: 6900, 6750 or 6111 kSym/sec)
// ==> pref(dB) = -174.0 + 6.5 + 68.5 + CnRef[modulation]{20,23,26,29,32}; (+/- 3 dB tuner specific)
if (mod == QAM_AUTO) mod = QAM_256;
// Q16 Q32 Q64 Q128 Q256
int pref = REF_C1(-79, -76, -73, -70, -67);
if (pref) {
int prel = (Strength / 1000) - pref;
ssi = (prel < -15) ? 0 :
(prel < 0) ? (prel + 15) * 2 / 3 : // 0% - 10%
(prel < 20) ? prel * 4 + 10 : // 10% - 90%
(prel < 35) ? (prel - 20) * 2 / 3 + 90 : // 90% - 100%
100;
#ifdef DEBUG_SIGNALSTRENGTH
fprintf(stderr, "SSI-C: STR:%d, Pref:%d, Prel:%d, ssi:%d%%(mod:%d)\n", Strength, pref, prel, ssi, mod);
#endif
}
}
else if (Channel->IsCable())
ssi = dB1000toPercent(Strength, -95000, -20000); // defaults
else if (Channel->IsSat())
ssi = dB1000toPercent(Strength, -95000, -20000); // defaults
return ssi;
}
#define IGNORE_BER 0
// Due to missing values or the different meanings of the reported error rate, ber_sqi is currently not taken into account
#define IGNORE_BER 1
#define BER_ERROR_FREE (1000*1000*1000) // 1/10^-9
int SignalToSQI(const cChannel *Channel, int Signal, int Ber, int FeModulation, int FeCoderateH, int FeFec)
@ -835,7 +854,7 @@ int SignalToSQI(const cChannel *Channel, int Signal, int Ber, int FeModulation,
}
}
else if (Channel->IsCable()) { // ! COMPLETELY UNTESTED !
if (mod == QAM_AUTO) mod = QAM_64;
if (mod == QAM_AUTO) mod = QAM_256;
// 0.1 dB Q16 Q32 Q64 Q128 Q256
int cnref = REF_C1(200, 230, 260, 290, 320); // minimum for BER<10^-4
if (cnref) {