tests/dtx: test detection/decoding of A[FH]S_SID_UPDATE
This patch extends the existing unit test coverage for AMR's special
DTX frames. The new tests confirm that the problem with unexpected
BER in decoded AFS_SID_UPDATE frames has been actually fixed [1].
Additionally this patch demonstrates another TCH/AHS specific problem,
which negatively affects RxQual-SUB measurements in osmo-bts-trx: the
actual content of AHS_SID_UPDATE_CN is decoded with ~50% BER, because
the burst buffer contains only half of the burst bits.
Change-Id: I434157e2091a306c039123cea08d84bd8533c937
Related: [1] I813081a4c0865958eee2496fe251ae17235ac842
Related: SYS#5853
diff --git a/tests/dtx/dtx_gsm0503_test.c b/tests/dtx/dtx_gsm0503_test.c
index b14c978..4ee5bf7 100644
--- a/tests/dtx/dtx_gsm0503_test.c
+++ b/tests/dtx/dtx_gsm0503_test.c
@@ -21,8 +21,12 @@
#include <stdio.h>
#include <stdint.h>
#include <osmocom/core/utils.h>
+#include <osmocom/coding/gsm0503_coding.h>
#include <osmocom/coding/gsm0503_amr_dtx.h>
+/* Length of payload bits in a Normal Burst */
+#define BURST_PLEN (57 * 2 + 2)
+
char sample_afs_sid_frame[] =
{
"111111110000000011001100101010100100010011111111001000100111011110011001001100111100110010011001111011100100010011111111001000100111011110011001001100111100110010011001111011100100010011111111001000100111011110011001001100111100110010011001111011100100010011111111001000100111011110011001001100111100110010011001111011100100010011111111001000100111011110011001001100111100110010011001111011100100010011111111001000100111011110011001001100111100110010011001"
@@ -108,6 +112,109 @@
n_errors, n_bits_total);
}
+static void test_gsm0503_tch_afhs_decode_dtx(const sbit_t *bursts, size_t offset,
+ enum gsm0503_amr_dtx_frames *amr_last_dtx,
+ bool full_rate, const char *test_desc)
+{
+ uint8_t tch_data[128]; /* just to be safe */
+ int n_errors = 0, n_bits_total = 0;
+ int rc;
+
+ printf("Running %s(at offset=%zu): testing %s\n", __func__, offset, test_desc);
+
+ /* Dummy (not really important) values */
+ uint8_t codec[4] = { 0, 1, 2, 3 };
+ int codecs = ARRAY_SIZE(codec);
+ uint8_t ul_cmr = 0;
+ uint8_t ul_ft = 0;
+
+ if (full_rate) {
+ rc = gsm0503_tch_afs_decode_dtx(&tch_data[0], &bursts[offset], false,
+ codec, codecs, &ul_ft, &ul_cmr,
+ &n_errors, &n_bits_total,
+ (uint8_t *)amr_last_dtx);
+ } else {
+ rc = gsm0503_tch_ahs_decode_dtx(&tch_data[0], &bursts[offset], false, false,
+ codec, codecs, &ul_ft, &ul_cmr,
+ &n_errors, &n_bits_total,
+ (uint8_t *)amr_last_dtx);
+ }
+ printf(" ==> gsm0503_tch_a%cs_decode_dtx() yields '%s' (rc=%d, BER %d/%d)\n",
+ full_rate ? 'f' : 'h', gsm0503_amr_dtx_frame_name(*amr_last_dtx),
+ rc, n_errors, n_bits_total);
+ if (rc > 0)
+ printf(" ====> tch_data[] = { %s }\n", osmo_hexdump_nospc(tch_data, rc));
+}
+
+static void test_gsm0503_tch_afhs_decode_dtx_sid_update(void)
+{
+ enum gsm0503_amr_dtx_frames amr_last_dtx = AMR_OTHER;
+ sbit_t bursts[BURST_PLEN * 12]; /* 12 bursts */
+ int rc;
+
+ /* 456 soft-bits containing an AFS_SID_UPDATE frame (captured on the air) */
+ const char *afs_sid_update = \
+ "94 81 83 76 7b 81 6b 7f 76 8c 81 81 81 86 71 7f 75 81 6d 7a 81 6b 7f 78 8a 87 70 75 8e"
+ "81 8d 7f 81 70 72 81 7f 85 86 7f 93 81 8a 74 7f 71 89 8a 75 7f 7f 78 8c 81 8b 7f 81 7f"
+ "7f 7f 70 8a 8b 7f 90 81 81 81 8a 77 7f 7f 70 81 70 71 86 8e 7f 81 7f 81 75 72 87 8c 76"
+ "7f 72 8e 81 81 81 81 92 7f 8c 81 92 7f 8c 89 7f 81 7f 8f 8b 77 76 86 8c 78 73 88 81 8b"
+ "81 7f 8c 85 77 7b 8d 81 81 81 8b 7f 81 7f 8e 81 8e 7f 8a 8a 7f 93 85 6b 7f 7f 72 81 6f"
+ "76 89 81 81 81 8a 73 7f 72 88 87 73 7f 73 81 7f 81 7f 92 87 73 78 81 6f 7f 71 81 76 77"
+ "6f 81 7f 81 71 7f 6e 81 75 77 83 81 81 90 7f 8b 88 76 76 8a 8d 76 74 81 7f 92 81 81 8b"
+ "78 72 81 77 76 81 6c 7c 8b 81 81 8d 7f 8b 81 8e 74 7f 7f 72 81 7f 81 74 7f 71 81 75 7f"
+ "8e 81 81 8c 72 79 85 8c 78 75 8c 8a 7f 90 81 8e 77 77 81 70 7f 7f 71 81 7f 81 7f 8e 89"
+ "7f 8f 81 8f 7f 8c 8d 7f 81 7f 81 6f 7f 71 8a 87 7f 81 6f 77 81 7f 8d 88 73 79 8a 8a 7f"
+ "7f 7f 7f 7f 76 8b 81 8c 77 7c 8a 81 91 7f 81 76 79 81 71 7f 7f 6f 84 8e 78 7f 7f 7f 74"
+ "88 86 7b 77 81 6f 7f 7f 7f 7f 7f 75 81 70 7f 76 89 81 81 81 8d 78 74 84 81 8e 7f 8d 8a"
+ "7f 79 8c 87 7f 81 7f 81 6f 7f 75 8d 8a 7f 81 7f 92 81 81 85 76 7f 6f 8c 88 6c 7f 73 91"
+ "81 8d 71 7f 7f 73 8d 88 7f 81 7f 91 86 6f 7f 73 8e 81 8d 79 78 81 72 74 8c 86 72 7f 77"
+ "6e 81 7f 81 77 76 81 72 74 81 6f 7f 6f 8d 81 91 7f 81 6d 7f 6d 81 6c 7f 6c 81 7f 81 7f"
+ "8c 8b 7f 8e 89 74 74 8c 81 81 81 81 81 92 7f 8e 8b 7f 93 81 8f 7f 90 81 8d 74 7b 8b 89";
+
+ memset(&bursts[0], 0, sizeof(bursts));
+ rc = osmo_hexparse(afs_sid_update, (uint8_t *)&bursts[BURST_PLEN * 4], BURST_PLEN * 8);
+ OSMO_ASSERT(rc == BURST_PLEN * 4);
+
+ /* Test detection of AFS_SID_UPDATE (marker) */
+ test_gsm0503_tch_afhs_decode_dtx(&bursts[0], BURST_PLEN * 0, &amr_last_dtx, true /* AFS */,
+ "detection of AFS_SID_UPDATE");
+
+ /* Test decoding of AFS_SID_UPDATE_CN (actual SID) */
+ test_gsm0503_tch_afhs_decode_dtx(&bursts[0], BURST_PLEN * 4, &amr_last_dtx, true /* AFS */,
+ "decoding of AFS_SID_UPDATE");
+
+ /* 456 soft-bits containing an AHS_SID_UPDATE frame (captured on the air) */
+ const char *ahs_sid_update = \
+ "81 67 7f 7f 7f 71 8f 88 6f 73 81 7e 81 6b 7f 7e 7d 6f 8f 8a 72 76 92 81 82 81 8f 6d 6f"
+ "81 7f 92 8c 7f 97 81 8e 6f 7f 7c 7f 6e 81 7e 81 6e 73 81 7f 93 8d 6f 7f 6c 81 6b 7f 72"
+ "7c 7c 7d 7f 6f 8f 81 94 7f 92 8d 6e 7d 7d 7f 6c 8b 8e 73 71 81 7f 92 90 7f 81 6e 6e 81"
+ "7f 94 8e 70 7f 6e 8c 8d 77 7f 6a 81 7f 81 70 6d 81 6c 71 8c 91 7f 90 8e 73 6e 81 6d 7f"
+ "81 8b 71 6e 81 7f 82 7c 81 7f 81 6d 73 81 6c 6d 81 6d 7f 6e 81 7e 81 6b 7f 7f 7f 6b 81"
+ "6e 6f 81 68 7f 71 91 81 82 81 8e 70 7f 7c 7d 7f 70 81 7f 91 8f 7f 81 6c 7f 71 81 6d 74"
+ "6f 8f 81 92 7f 82 7f 91 8b 7f 81 6b 7f 6d 81 6b 6f 81 6f 6e 90 81 81 92 7f 94 81 95 7f"
+ "96 81 96 70 7f 72 8f 81 95 7f 81 6f 70 81 7f 90 92 7f 81 6c 70 81 6b 7f 6f 8d 8d 7f 81"
+ "77 81 6a 7e 7e 73 92 8c 7f 81 6a 7f 6c 8e 8e 6e 7f 71 8e 8d 7e 81 6d 7f 6c 81 6d 6c 81"
+ "7f 94 81 92 7f 97 81 92 6e 7f 70 8c 8b 73 73 91 81 93 7f 81 70 72 81 7d 81 71 70 81 7f"
+ "7d 7f 6d 90 8d 73 76 92 81 92 6f 7d 7d 70 91 81 8f 73 75 8c 90 7f 94 81 91 70 7f 7d 7e"
+ "70 8d 8d 73 7f 7c 7e 6a 81 7e 81 6d 7f 6a 81 6f 7f 7f 71 8e 81 82 81 81 81 96 72 7e 7d"
+ "81 8d 7f 81 68 7f 7e 7c 7b 7f 6c 81 6a 7f 7f 71 8f 8d 7f 81 6c 72 8e 88 70 70 81 6d 70"
+ "8d 90 7f 81 7e 95 81 94 7f 92 8b 6e 7f 7f 70 8c 8c 73 75 91 81 91 6d 7d 7e 7b 7c 7d 71"
+ "6c 89 91 7f 81 7f 95 81 93 7f 95 90 7f 81 6d 70 81 6f 75 8c 8e 75 71 81 6e 70 8d 8d 7f"
+ "91 92 7f 81 7f 94 8d 70 71 81 6e 6d 81 6e 75 8e 81 93 70 7f 70 8f 8c 7f 81 6d 6f 81 6a";
+
+ memset(&bursts[0], 0, sizeof(bursts));
+ rc = osmo_hexparse(ahs_sid_update, (uint8_t *)&bursts[BURST_PLEN * 2], BURST_PLEN * 10);
+ OSMO_ASSERT(rc == BURST_PLEN * 4);
+
+ /* Test detection and decoding of AHS_SID_UPDATE */
+ test_gsm0503_tch_afhs_decode_dtx(&bursts[0], BURST_PLEN * 0, &amr_last_dtx, false /* AHS */,
+ "detection/decoding of AHS_SID_UPDATE");
+ test_gsm0503_tch_afhs_decode_dtx(&bursts[0], BURST_PLEN * 2, &amr_last_dtx, false /* AHS */,
+ "detection/decoding of AHS_SID_UPDATE");
+ test_gsm0503_tch_afhs_decode_dtx(&bursts[0], BURST_PLEN * 4, &amr_last_dtx, false /* AHS */,
+ "detection/decoding of AHS_SID_UPDATE");
+}
+
int main(int argc, char **argv)
{
printf("FR AMR DTX FRAMES:\n");
@@ -122,5 +229,7 @@
test_gsm0503_detect_ahs_dtx_frame(sample_sid_first_inh_frame);
test_gsm0503_detect_ahs_dtx_frame(sample_sid_update_inh_frame);
+ test_gsm0503_tch_afhs_decode_dtx_sid_update();
+
return EXIT_SUCCESS;
}