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Simplify the CTCSS and Noise Squelch decoders and logic.

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This commit is contained in:
Jonathan Naylor
2020-07-31 09:20:55 +01:00
parent b5ba384495
commit 2a001f491d
6 changed files with 58 additions and 95 deletions
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FMNoiseSquelch.cpp
+12 -18
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@@ -32,23 +32,21 @@ m_lowThreshold(0),
m_count(0U),
m_q0(0),
m_q1(0),
m_result(NS_NONE)
m_state(false)
{
}
void CFMNoiseSquelch::setParams(uint8_t highThreshold, uint8_t lowThreshold)
{
m_highThreshold = q31_t(highThreshold);
m_lowThreshold = q31_t(lowThreshold);
m_highThreshold = q31_t(highThreshold) * 20;
m_lowThreshold = q31_t(lowThreshold) * 20;
}
uint8_t CFMNoiseSquelch::process(q15_t sample)
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);
m_result &= ~NS_READY;
q31_t q2 = m_q1;
m_q1 = m_q0;
@@ -80,33 +78,29 @@ uint8_t CFMNoiseSquelch::process(q15_t sample)
// value = m_q0 * m_q0 + m_q1 * m_q1 - m_q0 * m_q1 * m_coeffDivTwo * 2
q31_t value = t2 + t4 - t9;
bool previousNSQValid = NSQ_VALID(m_result);
bool previousState = m_state;
q31_t threshold = m_highThreshold;
if (previousNSQValid)
if (previousState)
threshold = m_lowThreshold;
m_result |= NS_READY;
if (value < threshold)
m_result |= NS_VALID;
else
m_result &= ~NS_VALID;
m_state = value < threshold;
if (previousNSQValid != NSQ_VALID(m_result))
DEBUG4("Noise Squelch Value / Threshold / Valid", value, threshold, NSQ_VALID(m_result));
if (previousState != m_state)
DEBUG4("Noise Squelch Value / Threshold / Valid", value, threshold, m_state);
m_count = 0U;
m_q0 = 0;
m_q1 = 0;
}
return m_result;
return m_state;
}
void CFMNoiseSquelch::reset()
{
m_q0 = 0;
m_q1 = 0;
m_result = NS_NONE;
m_count = 0U;
m_state = false;
m_count = 0U;
}