EDGE: Add interfaces to enable EDGE transceiver
Create EDGE slot type in the Transceiver. When EDGE mode is enabled
for a particular slot, blind detection will be performed by
correlating against EDGE followed by normal bursts if no EDGE burst
is found.
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
diff --git a/Transceiver52M/Transceiver.cpp b/Transceiver52M/Transceiver.cpp
index 2be7ab0..255e120 100644
--- a/Transceiver52M/Transceiver.cpp
+++ b/Transceiver52M/Transceiver.cpp
@@ -367,7 +367,12 @@
return;
}
- burst = modulateBurst(bits, 8 + (wTime.TN() % 4 == 0), mSPSTx);
+ /* Use the number of bits as the EDGE burst indicator */
+ if (bits.size() == EDGE_BURST_NBITS)
+ burst = modulateEdgeBurst(bits, mSPSTx);
+ else
+ burst = modulateBurst(bits, 8 + (wTime.TN() % 4 == 0), mSPSTx);
+
scaleVector(*burst, txFullScale * pow(10, -RSSI / 10));
radio_burst = new radioVector(wTime, burst);
@@ -561,6 +566,13 @@
float threshold = 5.0, rc = 0;
switch (type) {
+ case EDGE:
+ rc = detectEdgeBurst(burst, mTSC, threshold, mSPSRx,
+ amp, toa, mMaxExpectedDelay);
+ if (rc > 0)
+ break;
+ else
+ type = TSC;
case TSC:
rc = analyzeTrafficBurst(burst, mTSC, threshold, mSPSRx,
amp, toa, mMaxExpectedDelay);
@@ -573,6 +585,8 @@
LOG(ERR) << "Invalid correlation type";
}
+ if (rc > 0)
+ return type;
return rc;
}
@@ -583,8 +597,11 @@
*/
SoftVector *Transceiver::demodulate(TransceiverState *state,
signalVector &burst, complex amp,
- float toa)
+ float toa, CorrType type)
{
+ if (type == EDGE)
+ return demodEdgeBurst(burst, mSPSRx, amp, toa);
+
return demodulateBurst(burst, mSPSRx, amp, toa);
}
@@ -606,7 +623,7 @@
double &timingOffset, double &noise,
size_t chan)
{
- int success;
+ int rc;
complex amp;
float toa, pow, max = -1.0, avg = 0.0;
int max_i = -1;
@@ -677,13 +694,14 @@
}
/* Detect normal or RACH bursts */
- success = detectBurst(state, *burst, amp, toa, type);
+ rc = detectBurst(state, *burst, amp, toa, type);
- /* Alert an error and exit */
- if (success <= 0) {
- if (success == -SIGERR_CLIP) {
+ if (rc > 0) {
+ type = (CorrType) rc;
+ } else if (rc <= 0) {
+ if (rc == -SIGERR_CLIP) {
LOG(WARNING) << "Clipping detected on received RACH or Normal Burst";
- } else if (success != SIGERR_NONE) {
+ } else if (rc != SIGERR_NONE) {
LOG(WARNING) << "Unhandled RACH or Normal Burst detection error";
}
@@ -693,7 +711,7 @@
timingOffset = toa / mSPSRx;
- bits = demodulate(state, *burst, amp, toa);
+ bits = demodulate(state, *burst, amp, toa, type);
delete radio_burst;
return bits;
@@ -916,6 +934,19 @@
}
}
+void Transceiver::logRxBurst(SoftVector *burst, GSM::Time time, double dbm,
+ double rssi, double noise, double toa)
+{
+ LOG(DEBUG) << std::fixed << std::right
+ << " time: " << time
+ << " RSSI: " << std::setw(5) << std::setprecision(1) << rssi
+ << "dBFS/" << std::setw(6) << -dbm << "dBm"
+ << " noise: " << std::setw(5) << std::setprecision(1) << noise
+ << "dBFS/" << std::setw(6) << -(noise + rssiOffset) << "dBm"
+ << " TOA: " << std::setw(5) << std::setprecision(2) << toa
+ << " bits: " << *burst;
+}
+
void Transceiver::driveReceiveFIFO(size_t chan)
{
SoftVector *rxBurst = NULL;
@@ -926,37 +957,39 @@
double noise; // noise level in dBFS
GSM::Time burstTime;
bool isRssiValid; // are RSSI, noise and burstTime valid
+ unsigned nbits = gSlotLen;
rxBurst = pullRadioVector(burstTime, RSSI, isRssiValid, TOA, noise, chan);
+ if (!rxBurst)
+ return;
- if (rxBurst) {
- dBm = RSSI+rssiOffset;
- TOAint = (int) (TOA * 256.0 + 0.5); // round to closest integer
+ /*
+ * EDGE demodulator returns 444 (148 * 3) bits
+ */
+ if (rxBurst->size() == gSlotLen * 3)
+ nbits = gSlotLen * 3;
- LOG(DEBUG) << std::fixed << std::right
- << " time: " << burstTime
- << " RSSI: " << std::setw(5) << std::setprecision(1) << RSSI << "dBFS/" << std::setw(6) << -dBm << "dBm"
- << " noise: " << std::setw(5) << std::setprecision(1) << noise << "dBFS/" << std::setw(6) << -(noise+rssiOffset) << "dBm"
- << " TOA: " << std::setw(5) << std::setprecision(2) << TOA
- << " bits: " << *rxBurst;
+ dBm = RSSI + rssiOffset;
+ logRxBurst(rxBurst, burstTime, dBm, RSSI, noise, TOA);
- char burstString[gSlotLen+10];
- burstString[0] = burstTime.TN();
- for (int i = 0; i < 4; i++)
- burstString[1+i] = (burstTime.FN() >> ((3-i)*8)) & 0x0ff;
- burstString[5] = (int)dBm;
- burstString[6] = (TOAint >> 8) & 0x0ff;
- burstString[7] = TOAint & 0x0ff;
- SoftVector::iterator burstItr = rxBurst->begin();
+ TOAint = (int) (TOA * 256.0 + 0.5); // round to closest integer
- for (unsigned int i = 0; i < gSlotLen; i++) {
- burstString[8+i] =(char) round((*burstItr++)*255.0);
- }
- burstString[gSlotLen+9] = '\0';
- delete rxBurst;
+ char burstString[nbits + 10];
+ burstString[0] = burstTime.TN();
+ for (int i = 0; i < 4; i++)
+ burstString[1+i] = (burstTime.FN() >> ((3-i)*8)) & 0x0ff;
+ burstString[5] = (int)dBm;
+ burstString[6] = (TOAint >> 8) & 0x0ff;
+ burstString[7] = TOAint & 0x0ff;
+ SoftVector::iterator burstItr = rxBurst->begin();
- mDataSockets[chan]->write(burstString,gSlotLen+10);
- }
+ for (unsigned i = 0; i < nbits; i++)
+ burstString[8 + i] = (char) round((*burstItr++) * 255.0);
+
+ burstString[nbits + 9] = '\0';
+ delete rxBurst;
+
+ mDataSockets[chan]->write(burstString, nbits + 10);
}
void Transceiver::driveTxFIFO()