From 9b5bbee265380b1452a1a04010a10ea0c4e1e637 Mon Sep 17 00:00:00 2001 From: Jonathan Naylor Date: Wed, 10 Jan 2018 21:39:29 +0000 Subject: [PATCH] Add actual NXDN values. --- NXDNDefines.h | 38 ++++++++++----------- NXDNRX.cpp | 92 +++++++++++++++++++++++++-------------------------- NXDNRX.h | 10 +++--- NXDNTX.cpp | 8 ++--- 4 files changed, 72 insertions(+), 76 deletions(-) diff --git a/NXDNDefines.h b/NXDNDefines.h index 1253b8e..956ffaf 100644 --- a/NXDNDefines.h +++ b/NXDNDefines.h @@ -21,34 +21,30 @@ const unsigned int NXDN_RADIO_SYMBOL_LENGTH = 5U; // At 24 kHz sample rate -const unsigned int NXDN_FRAME_LENGTH_BYTES = 120U; -const unsigned int NXDN_FRAME_LENGTH_BITS = NXDN_FRAME_LENGTH_BYTES * 8U; -const unsigned int NXDN_FRAME_LENGTH_SYMBOLS = NXDN_FRAME_LENGTH_BYTES * 4U; +const unsigned int NXDN_FRAME_LENGTH_BITS = 384U; +const unsigned int NXDN_FRAME_LENGTH_BYTES = NXDN_FRAME_LENGTH_BITS / 8U; +const unsigned int NXDN_FRAME_LENGTH_SYMBOLS = NXDN_FRAME_LENGTH_BITS / 2U; const unsigned int NXDN_FRAME_LENGTH_SAMPLES = NXDN_FRAME_LENGTH_SYMBOLS * NXDN_RADIO_SYMBOL_LENGTH; -const unsigned int NXDN_SYNC_LENGTH_BYTES = 5U; -const unsigned int NXDN_SYNC_LENGTH_BITS = NXDN_SYNC_LENGTH_BYTES * 8U; -const unsigned int NXDN_SYNC_LENGTH_SYMBOLS = NXDN_SYNC_LENGTH_BYTES * 4U; -const unsigned int NXDN_SYNC_LENGTH_SAMPLES = NXDN_SYNC_LENGTH_SYMBOLS * NXDN_RADIO_SYMBOL_LENGTH; +const unsigned int NXDN_FSW_LENGTH_BITS = 20U; +const unsigned int NXDN_FSW_LENGTH_SYMBOLS = NXDN_FSW_LENGTH_BITS / 2U; +const unsigned int NXDN_FSW_LENGTH_SAMPLES = NXDN_FSW_LENGTH_SYMBOLS * NXDN_RADIO_SYMBOL_LENGTH; -const unsigned int NXDN_FICH_LENGTH_BITS = 200U; -const unsigned int NXDN_FICH_LENGTH_SYMBOLS = 100U; -const unsigned int NXDN_FICH_LENGTH_SAMPLES = NXDN_FICH_LENGTH_SYMBOLS * NXDN_RADIO_SYMBOL_LENGTH; +const uint8_t NXDN_FSW_BYTES[] = {0x0CU, 0xDFU, 0x59U}; +const uint8_t NXDN_FSW_BYTES_MASK[] = {0x0FU, 0xFFU, 0xFFU}; +const uint8_t NXDN_FSW_BYTES_LENGTH = 3U; -const uint8_t NXDN_SYNC_BYTES[] = {0xD4U, 0x71U, 0xC9U, 0x63U, 0x4DU}; -const uint8_t NXDN_SYNC_BYTES_LENGTH = 5U; +const uint32_t NXDN_FSW_BITS = 0x000CDF59U; +const uint32_t NXDN_FSW_BITS_MASK = 0x000FFFFFU; -const uint64_t NXDN_SYNC_BITS = 0x000000D471C9634DU; -const uint64_t NXDN_SYNC_BITS_MASK = 0x000000FFFFFFFFFFU; +// C D F 5 9 +// 11 00 11 01 11 11 01 01 10 01 +// -3 +1 -3 +3 -3 -3 +3 +3 -1 +3 -// D 4 7 1 C 9 6 3 4 D -// 11 01 01 00 01 11 00 01 11 00 10 01 01 10 00 11 01 00 11 01 -// -3 +3 +3 +1 +3 -3 +1 +3 -3 +1 -1 +3 +3 -1 +3 -3 +3 +1 -3 +3 +const int8_t NXDN_FSW_SYMBOLS_VALUES[] = {-3, +1, -3, +3, -3, -3, +3, +3, -1, +3}; -const int8_t NXDN_SYNC_SYMBOLS_VALUES[] = {-3, +3, +3, +1, +3, -3, +1, +3, -3, +1, -1, +3, +3, -1, +3, -3, +3, +1, -3, +3}; - -const uint32_t NXDN_SYNC_SYMBOLS = 0x0007B5ADU; -const uint32_t NXDN_SYNC_SYMBOLS_MASK = 0x000FFFFFU; +const uint16_t NXDN_FSW_SYMBOLS = 0x014DU; +const uint16_t NXDN_FSW_SYMBOLS_MASK = 0x03FFU; #endif diff --git a/NXDNRX.cpp b/NXDNRX.cpp index 360a3a8..6087579 100644 --- a/NXDNRX.cpp +++ b/NXDNRX.cpp @@ -23,10 +23,10 @@ const q15_t SCALING_FACTOR = 18750; // Q15(0.55) -const uint8_t MAX_SYNC_BIT_START_ERRS = 2U; -const uint8_t MAX_SYNC_BIT_RUN_ERRS = 4U; +const uint8_t MAX_FSW_BIT_START_ERRS = 2U; +const uint8_t MAX_FSW_BIT_RUN_ERRS = 4U; -const uint8_t MAX_SYNC_SYMBOLS_ERRS = 3U; +const uint8_t MAX_FSW_SYMBOLS_ERRS = 3U; const uint8_t BIT_MASK_TABLE[] = {0x80U, 0x40U, 0x20U, 0x10U, 0x08U, 0x04U, 0x02U, 0x01U}; @@ -36,7 +36,7 @@ const uint8_t NOAVEPTR = 99U; const uint16_t NOENDPTR = 9999U; -const unsigned int MAX_SYNC_FRAMES = 4U + 1U; +const unsigned int MAX_FSW_FRAMES = 4U + 1U; CNXDNRX::CNXDNRX() : m_state(NXDNRXS_NONE), @@ -46,9 +46,9 @@ m_bitPtr(0U), m_dataPtr(0U), m_startPtr(NOENDPTR), m_endPtr(NOENDPTR), -m_syncPtr(NOENDPTR), -m_minSyncPtr(NOENDPTR), -m_maxSyncPtr(NOENDPTR), +m_fswPtr(NOENDPTR), +m_minFSWPtr(NOENDPTR), +m_maxFSWPtr(NOENDPTR), m_maxCorr(0), m_lostCount(0U), m_countdown(0U), @@ -71,9 +71,9 @@ void CNXDNRX::reset() m_averagePtr = NOAVEPTR; m_startPtr = NOENDPTR; m_endPtr = NOENDPTR; - m_syncPtr = NOENDPTR; - m_minSyncPtr = NOENDPTR; - m_maxSyncPtr = NOENDPTR; + m_fswPtr = NOENDPTR; + m_minFSWPtr = NOENDPTR; + m_maxFSWPtr = NOENDPTR; m_centreVal = 0; m_thresholdVal = 0; m_lostCount = 0U; @@ -117,7 +117,7 @@ void CNXDNRX::samples(const q15_t* samples, uint16_t* rssi, uint8_t length) void CNXDNRX::processNone(q15_t sample) { - bool ret = correlateSync(); + bool ret = correlateFSW(); if (ret) { // On the first sync, start the countdown to the state change if (m_countdown == 0U) { @@ -137,13 +137,13 @@ void CNXDNRX::processNone(q15_t sample) m_countdown--; if (m_countdown == 1U) { - m_minSyncPtr = m_syncPtr + NXDN_FRAME_LENGTH_SAMPLES - 1U; - if (m_minSyncPtr >= NXDN_FRAME_LENGTH_SAMPLES) - m_minSyncPtr -= NXDN_FRAME_LENGTH_SAMPLES; + m_minFSWPtr = m_fswPtr + NXDN_FRAME_LENGTH_SAMPLES - 1U; + if (m_minFSWPtr >= NXDN_FRAME_LENGTH_SAMPLES) + m_minFSWPtr -= NXDN_FRAME_LENGTH_SAMPLES; - m_maxSyncPtr = m_syncPtr + 1U; - if (m_maxSyncPtr >= NXDN_FRAME_LENGTH_SAMPLES) - m_maxSyncPtr -= NXDN_FRAME_LENGTH_SAMPLES; + m_maxFSWPtr = m_fswPtr + 1U; + if (m_maxFSWPtr >= NXDN_FRAME_LENGTH_SAMPLES) + m_maxFSWPtr -= NXDN_FRAME_LENGTH_SAMPLES; m_state = NXDNRXS_DATA; m_countdown = 0U; @@ -152,29 +152,29 @@ void CNXDNRX::processNone(q15_t sample) void CNXDNRX::processData(q15_t sample) { - if (m_minSyncPtr < m_maxSyncPtr) { - if (m_dataPtr >= m_minSyncPtr && m_dataPtr <= m_maxSyncPtr) - correlateSync(); + if (m_minFSWPtr < m_maxFSWPtr) { + if (m_dataPtr >= m_minFSWPtr && m_dataPtr <= m_maxFSWPtr) + correlateFSW(); } else { - if (m_dataPtr >= m_minSyncPtr || m_dataPtr <= m_maxSyncPtr) - correlateSync(); + if (m_dataPtr >= m_minFSWPtr || m_dataPtr <= m_maxFSWPtr) + correlateFSW(); } if (m_dataPtr == m_endPtr) { // Only update the centre and threshold if they are from a good sync - if (m_lostCount == MAX_SYNC_FRAMES) { - m_minSyncPtr = m_syncPtr + NXDN_FRAME_LENGTH_SAMPLES - 1U; - if (m_minSyncPtr >= NXDN_FRAME_LENGTH_SAMPLES) - m_minSyncPtr -= NXDN_FRAME_LENGTH_SAMPLES; + if (m_lostCount == MAX_FSW_FRAMES) { + m_minFSWPtr = m_fswPtr + NXDN_FRAME_LENGTH_SAMPLES - 1U; + if (m_minFSWPtr >= NXDN_FRAME_LENGTH_SAMPLES) + m_minFSWPtr -= NXDN_FRAME_LENGTH_SAMPLES; - m_maxSyncPtr = m_syncPtr + 1U; - if (m_maxSyncPtr >= NXDN_FRAME_LENGTH_SAMPLES) - m_maxSyncPtr -= NXDN_FRAME_LENGTH_SAMPLES; + m_maxFSWPtr = m_fswPtr + 1U; + if (m_maxFSWPtr >= NXDN_FRAME_LENGTH_SAMPLES) + m_maxFSWPtr -= NXDN_FRAME_LENGTH_SAMPLES; } calculateLevels(m_startPtr, NXDN_FRAME_LENGTH_SYMBOLS); - DEBUG4("NXDNRX: sync found pos/centre/threshold", m_syncPtr, m_centreVal, m_thresholdVal); + DEBUG4("NXDNRX: sync found pos/centre/threshold", m_fswPtr, m_centreVal, m_thresholdVal); uint8_t frame[NXDN_FRAME_LENGTH_BYTES + 3U]; samplesToBits(m_startPtr, NXDN_FRAME_LENGTH_SYMBOLS, frame, 8U, m_centreVal, m_thresholdVal); @@ -195,17 +195,17 @@ void CNXDNRX::processData(q15_t sample) m_countdown = 0U; m_maxCorr = 0; } else { - frame[0U] = m_lostCount == (MAX_SYNC_FRAMES - 1U) ? 0x01U : 0x00U; + frame[0U] = m_lostCount == (MAX_FSW_FRAMES - 1U) ? 0x01U : 0x00U; writeRSSIData(frame); m_maxCorr = 0; } } } -bool CNXDNRX::correlateSync() +bool CNXDNRX::correlateFSW() { - if (countBits32((m_bitBuffer[m_bitPtr] & NXDN_SYNC_SYMBOLS_MASK) ^ NXDN_SYNC_SYMBOLS) <= MAX_SYNC_SYMBOLS_ERRS) { - uint16_t ptr = m_dataPtr + NXDN_FRAME_LENGTH_SAMPLES - NXDN_SYNC_LENGTH_SAMPLES + NXDN_RADIO_SYMBOL_LENGTH; + if (countBits32((m_bitBuffer[m_bitPtr] & NXDN_FSW_SYMBOLS_MASK) ^ NXDN_FSW_SYMBOLS) <= MAX_FSW_SYMBOLS_ERRS) { + uint16_t ptr = m_dataPtr + NXDN_FRAME_LENGTH_SAMPLES - NXDN_FSW_LENGTH_SAMPLES + NXDN_RADIO_SYMBOL_LENGTH; if (ptr >= NXDN_FRAME_LENGTH_SAMPLES) ptr -= NXDN_FRAME_LENGTH_SAMPLES; @@ -213,7 +213,7 @@ bool CNXDNRX::correlateSync() q15_t min = 16000; q15_t max = -16000; - for (uint8_t i = 0U; i < NXDN_SYNC_LENGTH_SYMBOLS; i++) { + for (uint8_t i = 0U; i < NXDN_FSW_LENGTH_SYMBOLS; i++) { q15_t val = m_buffer[ptr]; if (val > max) @@ -221,7 +221,7 @@ bool CNXDNRX::correlateSync() if (val < min) min = val; - switch (NXDN_SYNC_SYMBOLS_VALUES[i]) { + switch (NXDN_FSW_SYMBOLS_VALUES[i]) { case +3: corr -= (val + val + val); break; @@ -249,31 +249,31 @@ bool CNXDNRX::correlateSync() m_thresholdVal = q15_t(v1 >> 15); } - uint16_t startPtr = m_dataPtr + NXDN_FRAME_LENGTH_SAMPLES - NXDN_SYNC_LENGTH_SAMPLES + NXDN_RADIO_SYMBOL_LENGTH; + uint16_t startPtr = m_dataPtr + NXDN_FRAME_LENGTH_SAMPLES - NXDN_FSW_LENGTH_SAMPLES + NXDN_RADIO_SYMBOL_LENGTH; if (startPtr >= NXDN_FRAME_LENGTH_SAMPLES) startPtr -= NXDN_FRAME_LENGTH_SAMPLES; - uint8_t sync[NXDN_SYNC_BYTES_LENGTH]; - samplesToBits(startPtr, NXDN_SYNC_LENGTH_SYMBOLS, sync, 0U, m_centreVal, m_thresholdVal); + uint8_t sync[NXDN_FSW_BYTES_LENGTH]; + samplesToBits(startPtr, NXDN_FSW_LENGTH_SYMBOLS, sync, 0U, m_centreVal, m_thresholdVal); uint8_t maxErrs; if (m_state == NXDNRXS_NONE) - maxErrs = MAX_SYNC_BIT_START_ERRS; + maxErrs = MAX_FSW_BIT_START_ERRS; else - maxErrs = MAX_SYNC_BIT_RUN_ERRS; + maxErrs = MAX_FSW_BIT_RUN_ERRS; uint8_t errs = 0U; - for (uint8_t i = 0U; i < NXDN_SYNC_BYTES_LENGTH; i++) - errs += countBits8(sync[i] ^ NXDN_SYNC_BYTES[i]); + for (uint8_t i = 0U; i < NXDN_FSW_BYTES_LENGTH; i++) + errs += countBits8((sync[i] & NXDN_FSW_BYTES_MASK[i]) ^ NXDN_FSW_BYTES[i]); if (errs <= maxErrs) { m_maxCorr = corr; - m_lostCount = MAX_SYNC_FRAMES; - m_syncPtr = m_dataPtr; + m_lostCount = MAX_FSW_FRAMES; + m_fswPtr = m_dataPtr; m_startPtr = startPtr; - m_endPtr = m_dataPtr + NXDN_FRAME_LENGTH_SAMPLES - NXDN_SYNC_LENGTH_SAMPLES - 1U; + m_endPtr = m_dataPtr + NXDN_FRAME_LENGTH_SAMPLES - NXDN_FSW_LENGTH_SAMPLES - 1U; if (m_endPtr >= NXDN_FRAME_LENGTH_SAMPLES) m_endPtr -= NXDN_FRAME_LENGTH_SAMPLES; diff --git a/NXDNRX.h b/NXDNRX.h index 7fc81f6..1bff2ac 100644 --- a/NXDNRX.h +++ b/NXDNRX.h @@ -37,15 +37,15 @@ public: private: NXDNRX_STATE m_state; - uint32_t m_bitBuffer[NXDN_RADIO_SYMBOL_LENGTH]; + uint16_t m_bitBuffer[NXDN_RADIO_SYMBOL_LENGTH]; q15_t m_buffer[NXDN_FRAME_LENGTH_SAMPLES]; uint16_t m_bitPtr; uint16_t m_dataPtr; uint16_t m_startPtr; uint16_t m_endPtr; - uint16_t m_syncPtr; - uint16_t m_minSyncPtr; - uint16_t m_maxSyncPtr; + uint16_t m_fswPtr; + uint16_t m_minFSWPtr; + uint16_t m_maxFSWPtr; q31_t m_maxCorr; uint16_t m_lostCount; uint8_t m_countdown; @@ -59,7 +59,7 @@ private: void processNone(q15_t sample); void processData(q15_t sample); - bool correlateSync(); + bool correlateFSW(); void calculateLevels(uint16_t start, uint16_t count); void samplesToBits(uint16_t start, uint16_t count, uint8_t* buffer, uint16_t offset, q15_t centre, q15_t threshold); void writeRSSIData(uint8_t* data); diff --git a/NXDNTX.cpp b/NXDNTX.cpp index d450e98..2e2ca0a 100644 --- a/NXDNTX.cpp +++ b/NXDNTX.cpp @@ -29,10 +29,10 @@ static q15_t RRC_0_2_FILTER[] = {0, 0, 0, 0, 850, 219, -720, -1548, -1795, -1172 -4544, -1431, 1447, 3073, 3120, 1927, 237, -1172, -1795, -1548, -720, 219, 850}; // numTaps = 45, L = 5 const uint16_t RRC_0_2_FILTER_PHASE_LEN = 9U; // phaseLength = numTaps/L -const q15_t NXDN_LEVELA = 1893; -const q15_t NXDN_LEVELB = 631; -const q15_t NXDN_LEVELC = -631; -const q15_t NXDN_LEVELD = -1893; +const q15_t NXDN_LEVELA = 1683; +const q15_t NXDN_LEVELB = 561; +const q15_t NXDN_LEVELC = -561; +const q15_t NXDN_LEVELD = -1683; const uint8_t NXDN_START_SYNC = 0x77U; const uint8_t NXDN_END_SYNC = 0xFFU;