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computeCI(): Rename verbose repeated getter to constant 

Change-Id: I9b426d01a282f572c0b915c5666642dce4c60475
This commit is contained in:
Pau Espin 2021-09-01 20:08:55 +02:00
parent d16eb314ed
commit 7f696801ae
1 changed files with 5 additions and 4 deletions
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9
Transceiver52M/sigProcLib.cpp
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@ -1464,20 +1464,21 @@ static signalVector *downsampleBurst(const signalVector &burst)
static float computeCI(const signalVector *burst, const CorrelationSequence *sync,
float toa, int start, const complex &xcorr)
{
const int N = sync->sequence->size();
float S, C;
int ps;
/* Integer position where the sequence starts */
ps = start + 1 - sync->sequence->size() + (int)roundf(toa);
ps = start + 1 - N + (int)roundf(toa);
/* Estimate Signal power */
S = 0.0f;
for (int i=0, j=ps; i<(int)sync->sequence->size(); i++,j++)
for (int i=0, j=ps; i<(int)N; i++,j++)
S += (*burst)[j].norm2();
S /= sync->sequence->size();
S /= N;
/* Esimate Carrier power */
C = xcorr.norm2() / ((sync->sequence->size() - 1) * sync->gain.abs());
C = xcorr.norm2() / ((N - 1) * sync->gain.abs());
/* Interference = Signal - Carrier, so C/I = C / (S - C) */
return 3.0103f * log2f(C / (S - C));