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lower_mac: Add puncturing schemes for voice channels

This commit is contained in:
Harald Welte 2011-05-27 10:38:24 +02:00
parent 025c3fc4c9
commit cb25e99b21
2 changed files with 38 additions and 5 deletions
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41
src/lower_mac/tetra_conv_enc.c
View File

@ -96,10 +96,15 @@ int conv_enc_init(struct conv_enc_state *ces)
const uint8_t P_rate2_3[] = { 0, 1, 2, 5 };
const uint8_t P_rate1_3[] = { 0, 1, 2, 3, 5, 6, 7 };
/* Voice */
const uint8_t P_rate8_12[] = { 0, 1, 2, 4 };
const uint8_t P_rate8_18[] = { 0, 1, 2, 3, 4, 5, 7, 8, 10, 11 };
struct puncturer {
enum tetra_rcpc_puncturer type;
const uint8_t *P;
uint8_t t;
uint8_t period;
uint32_t (*i_func)(uint32_t j);
};
@ -123,6 +128,7 @@ static const struct puncturer punct_2_3 = {
.type = TETRA_RCPC_PUNCT_2_3,
.P = P_rate2_3,
.t = 3,
.period = 8,
.i_func = &i_func_equals,
};
@ -131,6 +137,7 @@ static const struct puncturer punct_1_3 = {
.type = TETRA_RCPC_PUNCT_1_3,
.P = P_rate1_3,
.t = 6,
.period = 8,
.i_func = &i_func_equals,
};
@ -139,6 +146,7 @@ static const struct puncturer punct_292_432 = {
.type = TETRA_RCPC_PUNCT_292_432,
.P = P_rate2_3,
.t = 3,
.period = 8,
.i_func = &i_func_292,
};
@ -147,14 +155,35 @@ static const struct puncturer punct_148_432 = {
.type = TETRA_RCPC_PUNCT_148_432,
.P = P_rate1_3,
.t = 6,
.period = 8,
.i_func = &i_func_148,
};
/* EN 300 395-2 Section 5.5.2.1 */
static const struct puncturer punct_114_171 = {
.type = TETRA_RCPC_PUNCT_114_171,
.P = P_rate8_12,
.t = 3,
.period = 6,
.i_func = &i_func_equals,
};
/* EN 300 395-2 Section 5.5.2.2 */
static const struct puncturer punct_72_162 = {
.type = TETRA_RCPC_PUNCT_72_162,
.P = P_rate8_18,
.t = 9,
.period = 12,
.i_func = &i_func_equals,
};
static const struct puncturer *tetra_puncts[] = {
[TETRA_RCPC_PUNCT_2_3] = &punct_2_3,
[TETRA_RCPC_PUNCT_1_3] = &punct_1_3,
[TETRA_RCPC_PUNCT_292_432] = &punct_292_432,
[TETRA_RCPC_PUNCT_148_432] = &punct_148_432,
[TETRA_RCPC_PUNCT_114_171] = &punct_114_171,
[TETRA_RCPC_PUNCT_72_162] = &punct_72_162,
};
/* Puncture the mother code (in) and write 'len' symbols to out */
@ -175,7 +204,7 @@ int get_punctured_rate(enum tetra_rcpc_puncturer pu, uint8_t *in, int len, uint8
/* Section 8.2.3.1.2 */
for (j = 1; j <= len; j++) {
i = punct->i_func(j);
k = 8 * ((i-1)/t) + P[i - t*((i-1)/t)];
k = punct->period * ((i-1)/t) + P[i - t*((i-1)/t)];
DEBUGP("j = %u, i = %u, k = %u\n", j, i, k);
out[j-1] = in[k-1];
}
@ -200,7 +229,7 @@ int tetra_rcpc_depunct(enum tetra_rcpc_puncturer pu, const uint8_t *in, int len,
/* Section 8.2.3.1.2 */
for (j = 1; j <= len; j++) {
i = punct->i_func(j);
k = 8 * ((i-1)/t) + P[i - t*((i-1)/t)];
k = punct->period * ((i-1)/t) + P[i - t*((i-1)/t)];
DEBUGP("j = %u, i = %u, k = %u\n", j, i, k);
out[k-1] = in[j-1];
}
@ -220,6 +249,8 @@ static const struct punct_test_param punct_test_params[] = {
{ 144, 216, TETRA_RCPC_PUNCT_2_3 }, /* SCH/HD, BNCH, STCH */
{ 112, 168, TETRA_RCPC_PUNCT_2_3 }, /* SCH/HU */
{ 288, 432, TETRA_RCPC_PUNCT_2_3 }, /* SCH/F */
{ 114, 171, TETRA_RCPC_PUNCT_114_171 }, /* Speech class 1 */
{ 72, 162, TETRA_RCPC_PUNCT_72_162 }, /* Speech class 2 */
};
static int mother_memcmp(const uint8_t *mother, const uint8_t *depunct, int len)
@ -266,9 +297,9 @@ static int test_one_punct(const struct punct_test_param *ptp)
/* de-puncture into the depunct_buf (i.e. what happens at the receiver) */
tetra_rcpc_depunct(ptp->punct, type3_buf, ptp->type3_len, depunct_buf);
DEBUGP("MOTH: %s\n", hexdump(mother_buf, mother_len));
DEBUGP("PUNC: %s\n", hexdump(type3_buf, ptp->type3_len));
DEBUGP("DEPU: %s\n", hexdump(depunct_buf, mother_len));
DEBUGP("MOTH: %s\n", osmo_hexdump(mother_buf, mother_len));
DEBUGP("PUNC: %s\n", osmo_hexdump(type3_buf, ptp->type3_len));
DEBUGP("DEPU: %s\n", osmo_hexdump(depunct_buf, mother_len));
i = mother_memcmp(mother_buf, depunct_buf, mother_len);
if (i < 0) {

2
src/lower_mac/tetra_conv_enc.h
View File

@ -18,6 +18,8 @@ enum tetra_rcpc_puncturer {
TETRA_RCPC_PUNCT_1_3,
TETRA_RCPC_PUNCT_292_432,
TETRA_RCPC_PUNCT_148_432,
TETRA_RCPC_PUNCT_114_171,
TETRA_RCPC_PUNCT_72_162,
};
/* Puncture the mother code (in) and write 'len' symbols to out */