mirror of
https://github.com/saitohirga/WSJT-X.git
synced 2024-11-09 02:26:06 -05:00
4838d97370
git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@7340 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
270 lines
11 KiB
C
270 lines
11 KiB
C
// qra64.h
|
|
// Encoding/decoding functions for the QRA64 mode
|
|
//
|
|
// (c) 2016 - Nico Palermo, IV3NWV
|
|
// ------------------------------------------------------------------------------
|
|
// This file is part of the qracodes project, a Forward Error Control
|
|
// encoding/decoding package based on Q-ary RA (Repeat and Accumulate) LDPC codes.
|
|
//
|
|
// qracodes is free software: you can redistribute it and/or modify
|
|
// it under the terms of the GNU General Public License as published by
|
|
// the Free Software Foundation, either version 3 of the License, or
|
|
// (at your option) any later version.
|
|
// qracodes is distributed in the hope that it will be useful,
|
|
// but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
// GNU General Public License for more details.
|
|
|
|
// You should have received a copy of the GNU General Public License
|
|
// along with qracodes source distribution.
|
|
// If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
#ifndef _qra64_h_
|
|
#define _qra64_h_
|
|
|
|
// qra64_init(...) initialization flags
|
|
#define QRA_NOAP 0 // don't use a-priori knowledge
|
|
#define QRA_AUTOAP 1 // use auto a-priori knowledge
|
|
#define QRA_USERAP 2 // a-priori knowledge messages provided by the user
|
|
|
|
// QRA code parameters
|
|
#define QRA64_K 12 // information symbols
|
|
#define QRA64_N 63 // codeword length
|
|
#define QRA64_C 51 // (number of parity checks C=(N-K))
|
|
#define QRA64_M 64 // code alphabet size
|
|
#define QRA64_m 6 // bits per symbol
|
|
|
|
// packed predefined callsigns and fields as defined in JT65
|
|
#define CALL_CQ 0xFA08319
|
|
#define CALL_QRZ 0xFA0831A
|
|
#define CALL_CQ000 0xFA0831B
|
|
#define CALL_CQ999 0xFA08702
|
|
#define CALL_CQDX 0x5624C39
|
|
#define CALL_DE 0xFF641D1
|
|
#define GRID_BLANK 0x7E91
|
|
|
|
// Types of a-priori knowledge messages
|
|
#define APTYPE_CQQRZ 0 // [cq/qrz ? ?/blank]
|
|
#define APTYPE_MYCALL 1 // [mycall ? ?/blank]
|
|
#define APTYPE_HISCALL 2 // [? hiscall ?/blank]
|
|
#define APTYPE_BOTHCALLS 3 // [mycall hiscall ?]
|
|
#define APTYPE_FULL 4 // [mycall hiscall grid]
|
|
#define APTYPE_CQHISCALL 5 // [cq/qrz hiscall ?/blank]
|
|
#define APTYPE_SIZE (APTYPE_CQHISCALL+1)
|
|
|
|
typedef struct {
|
|
float decEsNoMetric;
|
|
int apflags;
|
|
int apmsg_set[APTYPE_SIZE]; // indicate which ap type knowledge has
|
|
// been set by the user
|
|
// ap messages buffers
|
|
int apmsg_cqqrz[12]; // [cq/qrz ? ?/blank]
|
|
int apmsg_call1[12]; // [mycall ? ?/blank]
|
|
int apmsg_call2[12]; // [? hiscall ?/blank]
|
|
int apmsg_call1_call2[12]; // [mycall hiscall ?]
|
|
int apmsg_call1_call2_grid[12]; // [mycall hiscall grid]
|
|
int apmsg_cq_call2[12]; // [cq hiscall ?/blank]
|
|
int apmsg_cq_call2_grid[12]; // [cq hiscall grid]
|
|
|
|
// ap messages masks
|
|
int apmask_cqqrz[12];
|
|
int apmask_cqqrz_ooo[12];
|
|
int apmask_call1[12];
|
|
int apmask_call1_ooo[12];
|
|
int apmask_call2[12];
|
|
int apmask_call2_ooo[12];
|
|
int apmask_call1_call2[12];
|
|
int apmask_call1_call2_grid[12];
|
|
int apmask_cq_call2[12];
|
|
int apmask_cq_call2_ooo[12];
|
|
} qra64codec;
|
|
|
|
#ifdef __cplusplus
|
|
extern "C" {
|
|
#endif
|
|
|
|
qra64codec *qra64_init(int flags);
|
|
// QRA64 mode initialization function
|
|
// arguments:
|
|
// flags: set the decoder mode
|
|
// QRA_NOAP use no a-priori information
|
|
// QRA_AUTOAP use any relevant previous decodes
|
|
// QRA_USERAP use a-priori information provided via qra64_apset(...)
|
|
// returns:
|
|
// Pointer to initialized qra64codec data structure
|
|
// this pointer should be passed to the encoding/decoding functions
|
|
//
|
|
// 0 if unsuccessful (can't allocate memory)
|
|
// ----------------------------------------------------------------------------
|
|
|
|
void qra64_encode(qra64codec *pcodec, int *y, const int *x);
|
|
// QRA64 encoder
|
|
// arguments:
|
|
// pcodec = pointer to a qra64codec data structure as returned by qra64_init
|
|
// x = pointer to the message to be encoded, int x[12]
|
|
// x must point to an array of integers (i.e. defined as int x[12])
|
|
// y = pointer to encoded message, int y[63]=
|
|
// ----------------------------------------------------------------------------
|
|
|
|
int qra64_decode(qra64codec *pcodec, float *ebno, int *x, const float *r);
|
|
// QRA64 mode decoder
|
|
// arguments:
|
|
// pcodec = pointer to a qra64codec data structure as returned by qra64_init
|
|
// ebno = pointer to a float where the avg Eb/No (in dB) will be stored
|
|
// in case of successfull decoding
|
|
// (pass a null pointer if not interested)
|
|
// x = pointer to decoded message, int x[12]
|
|
// r = pointer to received symbol energies (squared amplitudes)
|
|
// r must point to an array of length QRA64_M*QRA64_N (=64*63=4032)
|
|
// The first QRA_M entries should be the energies of the first
|
|
// symbol in the codeword; the last QRA_M entries should be the
|
|
// energies of the last symbol in the codeword
|
|
//
|
|
// return code:
|
|
//
|
|
// The return code is <0 when decoding is unsuccessful
|
|
// -16 indicates that the definition of QRA64_NMSG does not match what required by the code
|
|
// If the decoding process is successfull the return code is accordingly to the following table
|
|
// rc=0 [? ? ?] AP0 (decoding with no a-priori)
|
|
// rc=1 [CQ ? ?] AP27
|
|
// rc=2 [CQ ? ] AP44
|
|
// rc=3 [CALL ? ?] AP29
|
|
// rc=4 [CALL ? ] AP45
|
|
// rc=5 [CALL CALL ?] AP57
|
|
// rc=6 [? CALL ?] AP29
|
|
// rc=7 [? CALL ] AP45
|
|
// rc=8 [CALL CALL GRID] AP72 (actually a AP68 mask to reduce false decodes)
|
|
// rc=9 [CQ CALL ?] AP55
|
|
// rc=10 [CQ CALL ] AP70 (actaully a AP68 mask to reduce false decodes)
|
|
|
|
// return codes in the range 1-10 indicate the amount and the type of a-priori
|
|
// information was required to decode the received message.
|
|
|
|
|
|
// Decode a QRA64 msg using a fast-fading metric
|
|
int qra64_decode_fastfading(
|
|
qra64codec *pcodec, // ptr to the codec structure
|
|
float *ebno, // ptr to where the estimated Eb/No value will be saved
|
|
int *x, // ptr to decoded message
|
|
const float *rxen, // ptr to received symbol energies array
|
|
const int submode, // submode idx (0=QRA64A ... 4=QRA64E)
|
|
const float B90, // spread bandwidth (90% fractional energy)
|
|
const int fadingModel); // 0=Gaussian 1=Lorentzian fade model
|
|
//
|
|
// rxen: The array of the received bin energies
|
|
// Bins must be spaced by integer multiples of the symbol rate (1/Ts Hz)
|
|
// The array must be an array of total length U = L x N where:
|
|
// L: is the number of frequency bins per message symbol (see after)
|
|
// N: is the number of symbols in a QRA64 msg (63)
|
|
//
|
|
// The number of bins/symbol L depends on the selected submode accordingly to
|
|
// the following rule:
|
|
// L = (64+64*2^submode+64) = 64*(2+2^submode)
|
|
// Tone 0 is always supposed to be at offset 64 in the array.
|
|
// The m-th tone nominal frequency is located at offset 64 + m*2^submode (m=0..63)
|
|
//
|
|
// Submode A: (2^submode = 1)
|
|
// L = 64*3 = 196 bins/symbol
|
|
// Total length of the energies array: U = 192*63 = 12096 floats
|
|
//
|
|
// Submode B: (2^submode = 2)
|
|
// L = 64*4 = 256 bins/symbol
|
|
// Total length of the energies array: U = 256*63 = 16128 floats
|
|
//
|
|
// Submode C: (2^submode = 4)
|
|
// L = 64*6 = 384 bins/symbol
|
|
// Total length of the energies array: U = 384*63 = 24192 floats
|
|
//
|
|
// Submode D: (2^submode = 8)
|
|
// L = 64*10 = 640 bins/symbol
|
|
// Total length of the energies array: U = 640*63 = 40320 floats
|
|
//
|
|
// Submode E: (2^submode = 16)
|
|
// L = 64*18 = 1152 bins/symbol
|
|
// Total length of the energies array: U = 1152*63 = 72576 floats
|
|
//
|
|
// Note: The rxen array is modified and reused for internal calculations.
|
|
//
|
|
//
|
|
// B90: spread fading bandwidth in Hz (90% fractional average energy)
|
|
//
|
|
// B90 should be in the range 1 Hz ... 238 Hz
|
|
// The value passed to the call is rounded to the closest value among the
|
|
// 64 available values:
|
|
// B = 1.09^k Hz, with k=0,1,...,63
|
|
//
|
|
// I.e. B90=27 Hz will be approximated in this way:
|
|
// k = rnd(log(27)/log(1.09)) = 38
|
|
// B90 = 1.09^k = 1.09^38 = 26.4 Hz
|
|
//
|
|
// For any input value the maximum rounding error is not larger than +/- 5%
|
|
//
|
|
// return codes: same return codes of qra64_decode (+some additional error codes)
|
|
|
|
|
|
// Simulate the fast-fading channel (to be used with qra64_decode_fastfading)
|
|
int qra64_fastfading_channel(
|
|
float **rxen,
|
|
const int *xmsg,
|
|
const int submode,
|
|
const float EbN0dB,
|
|
const float B90,
|
|
const int fadingModel);
|
|
// Simulate transmission over a fading channel with given B90, fading model and submode
|
|
// and non coherent detection.
|
|
// Sets rxen to point to an array of bin energies formatted as required
|
|
// by the (fast-fading) decoding routine.
|
|
// returns 0 on success or negative values on error conditions
|
|
|
|
|
|
int qra64_apset(qra64codec *pcodec, const int mycall, const int hiscall, const int grid, const int aptype);
|
|
// Set decoder a-priori knowledge accordingly to the type of the message to
|
|
// look up for
|
|
// arguments:
|
|
// pcodec = pointer to a qra64codec data structure as returned by qra64_init
|
|
// mycall = mycall to look for
|
|
// hiscall = hiscall to look for
|
|
// grid = grid to look for
|
|
// aptype = define the type of AP to be set:
|
|
// APTYPE_CQQRZ set [cq/qrz ? ?/blank]
|
|
// APTYPE_MYCALL set [mycall ? ?/blank]
|
|
// APTYPE_HISCALL set [? hiscall ?/blank]
|
|
// APTYPE_BOTHCALLS set [mycall hiscall ?]
|
|
// APTYPE_FULL set [mycall hiscall grid]
|
|
// APTYPE_CQHISCALL set [cq/qrz hiscall ?/blank]
|
|
|
|
// returns:
|
|
// 0 on success
|
|
// -1 when qra64_init was called with the QRA_NOAP flag
|
|
// -2 invalid apytpe (valid range [APTYPE_CQQRZ..APTYPE_CQHISCALL]
|
|
// (APTYPE_CQQRZ [cq/qrz ? ?] is set by default )
|
|
|
|
void qra64_apdisable(qra64codec *pcodec, const int aptype);
|
|
// disable specific AP type
|
|
// arguments:
|
|
// pcodec = pointer to a qra64codec data structure as returned by qra64_init
|
|
// aptype = define the type of AP to be disabled
|
|
// APTYPE_CQQRZ disable [cq/qrz ? ?/blank]
|
|
// APTYPE_MYCALL disable [mycall ? ?/blank]
|
|
// APTYPE_HISCALL disable [ ? hiscall ?/blank]
|
|
// APTYPE_BOTHCALLS disable [mycall hiscall ? ]
|
|
// APTYPE_FULL disable [mycall hiscall grid]
|
|
// APTYPE_CQHISCALL set [cq/qrz hiscall ?/blank]
|
|
|
|
void qra64_close(qra64codec *pcodec);
|
|
// Free memory allocated by qra64_init
|
|
// arguments:
|
|
// pcodec = pointer to a qra64codec data structure as returned by qra64_init
|
|
|
|
// ----------------------------------------------------------------------------
|
|
|
|
// encode/decode std msgs in 12 symbols as done in jt65
|
|
void encodemsg_jt65(int *y, const int call1, const int call2, const int grid);
|
|
void decodemsg_jt65(int *call1, int *call2, int *grid, const int *x);
|
|
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|
|
|
|
#endif // _qra64_h_
|