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MMDVM
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Merge pull request #297 from F4FXL/AX25_FM 

Add some delay to squelch
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Jonathan Naylor 2020-08-05 22:16:37 +01:00 committed by GitHub
parent 1ad9799123 625ec93af8
commit 8d9b49bdb0
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2 changed files with 30 additions and 7 deletions
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35
FMNoiseSquelch.cpp
View File

@ -32,20 +32,22 @@ m_lowThreshold(0),
m_count(0U),
m_q0(0),
m_q1(0),
m_state(false)
m_state(false),
m_validCount(0U)
{
}
void CFMNoiseSquelch::setParams(uint8_t highThreshold, uint8_t lowThreshold)
{
m_highThreshold = q31_t(highThreshold) * 20;
m_lowThreshold = q31_t(lowThreshold) * 20;
m_highThreshold = q31_t(highThreshold);
m_lowThreshold = q31_t(lowThreshold);
}
bool CFMNoiseSquelch::process(q15_t sample)
{
//get more dynamic into the decoder by multiplying the sample by 1.5
q31_t sample31 = q31_t(sample) + (q31_t(sample) >> 1);
//get more dynamic into the decoder by multiplying the sample by 64
q31_t sample31 = q31_t(sample) << 6; //+ (q31_t(sample) >> 1);
q31_t q2 = m_q1;
m_q1 = m_q0;
@ -84,10 +86,29 @@ bool CFMNoiseSquelch::process(q15_t sample)
if (previousState)
threshold = m_lowThreshold;
m_state = value < threshold;
if (!m_state) {
if (value < threshold)
m_validCount++;
else
m_validCount = 0U;
}
if (previousState != m_state)
if (m_state) {
if (value >= threshold)
m_invalidCount++;
else
m_invalidCount = 0U;
}
m_state = m_validCount >= 10U && m_invalidCount < 10U;
if(previousState && !m_state)
m_invalidCount = 0U;
if (previousState != m_state) {
DEBUG4("Noise Squelch Value / Threshold / Valid", value, threshold, m_state);
DEBUG3("Valid Count / Invalid Count", m_validCount, m_invalidCount);
}
m_count = 0U;
m_q0 = 0;

2
FMNoiseSquelch.h
View File

@ -38,6 +38,8 @@ private:
q31_t m_q0;
q31_t m_q1;
bool m_state;
uint8_t m_validCount;
uint8_t m_invalidCount;
};
#endif