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Fine tune.

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This commit is contained in:
John Greb 2015-01-28 00:02:49 +00:00
parent 1982574527
commit bfdd03e903
2 changed files with 32 additions and 17 deletions
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48
plugins/channel/lora/lorademod.cpp
View File

@ -48,6 +48,7 @@ LoRaDemod::LoRaDemod(SampleSink* sampleSink) :
mov = new float[4*LORA_SFFT_LEN];
history = new short[1024];
finetune = new short[16];
}
LoRaDemod::~LoRaDemod()
@ -60,6 +61,8 @@ LoRaDemod::~LoRaDemod()
delete [] mov;
if (history)
delete [] history;
if (finetune)
delete [] finetune;
}
void LoRaDemod::configure(MessageQueue* messageQueue, Real Bandwidth)
@ -70,33 +73,40 @@ void LoRaDemod::configure(MessageQueue* messageQueue, Real Bandwidth)
void LoRaDemod::dumpRaw()
{
int i, j, max;
max = m_time - 4;
if (max > 32 * 4)
max = 32 * 4;
short bin, j, max;
max = m_time / 4 - 1;
if (max > 32)
max = 32;
char text[256];
for ( i=0; i < max; i+=4) {
j = i / 4;
text[j] = 32 + (toGray(127 & history[i + 4]) >> 1);
for ( j=0; j < max; j++) {
bin = (history[j * 4 + 4] + m_tune) & (LORA_SFFT_LEN - 1);
text[j] = 32 + (toGray(bin) >> 1);
}
text[i / 4] = 0;
text[j] = 0;
printf(">%s..(%d)\n", text, m_time / 4);
}
short LoRaDemod::synch(short bin)
{
short i, j;
if (bin < 0) {
if (m_time > 70)
dumpRaw();
m_time = 0;
return -1;
}
history[m_time] = (bin + m_tune) & (LORA_SFFT_LEN - 1);
history[m_time] = bin;
if (m_time > 12)
if (history[m_time] == history[m_time - 6])
if (history[m_time] == history[m_time - 12]) {
m_time = 0;
if (bin == history[m_time - 6])
if (bin == history[m_time - 12]) {
m_tune = LORA_SFFT_LEN - bin;
j = 0;
for (i=0; i<12; i++)
j += finetune[15 & (m_time - i)];
if (j < 0)
m_tune += 1;
m_tune &= (LORA_SFFT_LEN - 1);
m_time = 0;
return -1;
}
@ -109,6 +119,7 @@ short LoRaDemod::synch(short bin)
int LoRaDemod::detect(Complex c, Complex a)
{
int p, q;
short i, result, negresult, movpoint;
float peak, negpeak, tfloat;
float mag[LORA_SFFT_LEN];
@ -139,11 +150,14 @@ int LoRaDemod::detect(Complex c, Complex a)
}
mov[movpoint * LORA_SFFT_LEN + i] = mag[i];
}
if (peak > negpeak * 4) {
result = synch(result);
} else {
result = synch(-1);
}
p = (result - 1 + LORA_SFFT_LEN) & (LORA_SFFT_LEN -1);
q = (result + 1) & (LORA_SFFT_LEN -1);
finetune[15 & m_time] = (mag[p] > mag[q]) ? -1 : 1;
if (peak < negpeak * 4)
result = -1;
result = synch(result);
if (result >= 0)
m_result = result;
return m_result;

1
plugins/channel/lora/lorademod.h
View File

@ -85,6 +85,7 @@ private:
sfft* negaFilter;
float* mov;
short* history;
short* finetune;
NCO m_nco;
Interpolator m_interpolator;