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Merge branch 'boxcar' into boxcar_dstar_correlator

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This commit is contained in:
Jonathan Naylor
2017-08-02 20:36:57 +01:00
parent 7f8a0a71f5 469be87dc3
commit 13f340917e
8 changed files with 97 additions and 46 deletions
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DStarRX.cpp
+29 -4
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@@ -233,6 +233,10 @@ const uint16_t CCITT_TABLE[] = {
const uint16_t NOENDPTR = 9999U;
// Generated using [b, a] = butter(1, 0.001) in MATLAB
static q31_t DC_FILTER[] = {3367972, 0, 3367972, 0, 2140747704, 0}; // {b0, 0, b1, b2, -a1, -a2}
const uint32_t DC_FILTER_STAGES = 1U; // One Biquad stage
CDStarRX::CDStarRX() :
m_rxState(DSRXS_NONE),
m_bitBuffer(),
@@ -257,8 +261,16 @@ m_pathMemory2(),
m_pathMemory3(),
m_fecOutput(),
m_rssiAccum(0U),
m_rssiCount(0U)
m_rssiCount(0U),
m_dcFilter(),
m_dcState()
{
::memset(m_dcState, 0x00U, 4U * sizeof(q31_t));
m_dcFilter.numStages = DC_FILTER_STAGES;
m_dcFilter.pState = m_dcState;
m_dcFilter.pCoeffs = DC_FILTER;
m_dcFilter.postShift = 0;
}
void CDStarRX::reset()
@@ -279,13 +291,26 @@ void CDStarRX::reset()
m_rssiCount = 0U;
}
void CDStarRX::samples(const q15_t* samples, const uint16_t* rssi, uint8_t length)
{
void CDStarRX::samples(q15_t* samples, const uint16_t* rssi, uint8_t length)
{
q31_t dcLevel = 0;
q31_t dcVals[20U];
q31_t q31Samples[20U];
::arm_q15_to_q31(samples, q31Samples, length);
::arm_biquad_cascade_df1_q31(&m_dcFilter, q31Samples, dcVals, length);
for (uint8_t i = 0U; i < length; i++)
dcLevel += dcVals[i];
dcLevel /= length;
q15_t offset = q15_t(__SSAT((dcLevel >> 16), 16));
for (uint16_t i = 0U; i < length; i++) {
m_rssiAccum += rssi[i];
m_rssiCount++;
q15_t sample = samples[i];
q15_t sample = samples[i] - offset;
m_bitBuffer[m_bitPtr] <<= 1;
if (sample < 0)