diff options
| author | Thomas Tsou <ttsou@vt.edu> | 2012-03-20 16:29:43 -0400 |
|---|---|---|
| committer | Alexander Chemeris <Alexander.Chemeris@gmail.com> | 2013-06-24 01:51:02 +0400 |
| commit | afb04f8b631b6727db0bc62802f2bf50cf39503a (patch) | |
| tree | 893633210ebf37de52ca3abb6503074f70cd801c | |
| parent | 5f13377b83bc5bfafaf6b150a4b507f190cee585 (diff) | |
multi-arfcn, trx: fix infinite energy threshold bug
This fixes a bug where the energy threshold may reach infinity.
The transceiver energy detection threshold increase is
dependent on elapsed frames and the previous false detection
time. If we assume a (0,0) start time with the actual start
time - randomly determined - it's possible to get very
large elapsed frame counts at start. Once the threshold hits
'inf' further calculations are impossible and transceiver
is locked out from use.
Use the actual start time for initializing variables so
we avoid this scenario.
Signed-off-by: Thomas Tsou <ttsou@vt.edu>
| -rw-r--r-- | Transceiver52M/DriveLoop.cpp | 9 | ||||
| -rw-r--r-- | Transceiver52M/DriveLoop.h | 3 | ||||
| -rw-r--r-- | Transceiver52M/Transceiver.cpp | 6 |
3 files changed, 11 insertions, 7 deletions
diff --git a/Transceiver52M/DriveLoop.cpp b/Transceiver52M/DriveLoop.cpp index cbd2993..c925d20 100644 --- a/Transceiver52M/DriveLoop.cpp +++ b/Transceiver52M/DriveLoop.cpp @@ -33,12 +33,13 @@ DriveLoop::DriveLoop(int wSamplesPerSymbol, mSamplesPerSymbol = wSamplesPerSymbol; mRadioInterface = wRadioInterface; - GSM::Time startTime(random() % gHyperframe, 0); - mTransmitDeadlineClock = startTime; - mLatencyUpdateTime = startTime; + mStartTime = (random() % gHyperframe, 0); + + mTransmitDeadlineClock = mStartTime; + mLatencyUpdateTime = mStartTime; mTransmitLatency = wTransmitLatency; - mRadioInterface->getClock()->set(startTime); + mRadioInterface->getClock()->set(mStartTime); // generate pulse and setup up signal processing library gsmPulse = generateGSMPulse(2, mSamplesPerSymbol); diff --git a/Transceiver52M/DriveLoop.h b/Transceiver52M/DriveLoop.h index df54ef7..593ef58 100644 --- a/Transceiver52M/DriveLoop.h +++ b/Transceiver52M/DriveLoop.h @@ -58,6 +58,7 @@ private: Thread *mRadioDriveLoopThread; ///< thread to push/pull bursts into transmit/receive FIFO GSM::Time mTransmitDeadlineClock; ///< deadline for pushing bursts into transmit FIFO + GSM::Time mStartTime; ///< random start time of the radio clock RadioInterface *mRadioInterface; ///< associated radioInterface object double txFullScale; ///< full scale input to radio @@ -149,6 +150,8 @@ public: mChanType[m][timeslot] = comb; } + GSM::Time getStartTime() { return mStartTime; } + private: ChannelCombination mChanType[CHAN_M][8]; ///< channel types for all timeslots diff --git a/Transceiver52M/Transceiver.cpp b/Transceiver52M/Transceiver.cpp index ff8c12e..0d7776f 100644 --- a/Transceiver52M/Transceiver.cpp +++ b/Transceiver52M/Transceiver.cpp @@ -66,7 +66,7 @@ Transceiver::Transceiver(int wBasePort, mSamplesPerSymbol = wSamplesPerSymbol; mRadioInterface = wRadioInterface; - mLastClockUpdateTime = GSM::Time(0, 0); + mLastClockUpdateTime = mDriveLoop->getStartTime(); mMaxExpectedDelay = 0; mTransmitDeadlineClock = wDriveLoop->deadlineClock(); @@ -83,7 +83,7 @@ Transceiver::Transceiver(int wBasePort, channelResponse[i] = NULL; DFEForward[i] = NULL; DFEFeedback[i] = NULL; - channelEstimateTime[i] = GSM::Time(0, 0); + channelEstimateTime[i] = mDriveLoop->getStartTime(); } mOn = false; @@ -92,7 +92,7 @@ Transceiver::Transceiver(int wBasePort, mRxFreq = 0.0; mPower = -10; mEnergyThreshold = INIT_ENERGY_THRSHD; - prevFalseDetectionTime = GSM::Time(0, 0); + prevFalseDetectionTime = mDriveLoop->getStartTime(); mRadioLocked = mRadioInterface->started(); } |