diff options
| author | Andreas Eversberg <jolly@eversberg.eu> | 2013-02-27 12:04:27 +0100 |
|---|---|---|
| committer | Steve Markgraf <steve@steve-m.de> | 2021-10-23 18:51:19 +0200 |
| commit | 2318cc993d88f66670f9b1dfe2e40e7b3736bd09 (patch) | |
| tree | fe4012e2190235d9bc0fba64345c51a43802ca2d | |
| parent | 5f71fbcb706388a64a167265f0cf249cbf0a708b (diff) | |
Tansceiver checks quality of RACH, before forwarding it to TRX interface
By checking peak level of RACH's training sequence, only peaks that are
good enough are forwarded to the TRX interface. If any received noise
would be forwarded, there would be too many false detection, due to weak
CRC protection of RACH.
| -rw-r--r-- | src/host/layer23/src/transceiver/demod.c | 4 | ||||
| -rw-r--r-- | src/host/layer23/src/transceiver/l1ctl.c | 9 |
2 files changed, 10 insertions, 3 deletions
diff --git a/src/host/layer23/src/transceiver/demod.c b/src/host/layer23/src/transceiver/demod.c index 45b0570a..c7a2d15f 100644 --- a/src/host/layer23/src/transceiver/demod.c +++ b/src/host/layer23/src/transceiver/demod.c @@ -64,6 +64,10 @@ gsm_ab_ind_process(struct app_state *as, if (rv) goto err; + /* Check for a significant peak */ + if (cabsf(chan) < 0.5) + goto err; + printf("TOA : %f\n", toa); printf("chan : (%f %f) => %f\n", crealf(chan), cimagf(chan), cabsf(chan)); diff --git a/src/host/layer23/src/transceiver/l1ctl.c b/src/host/layer23/src/transceiver/l1ctl.c index 96ca869b..afdeb171 100644 --- a/src/host/layer23/src/transceiver/l1ctl.c +++ b/src/host/layer23/src/transceiver/l1ctl.c @@ -233,12 +233,15 @@ _l1ctl_rx_bts_burst_ab_ind(struct app_state *as, struct msgb *msg) fn = ntohl(bi->fn); - LOGP(DL1C, LOGL_INFO, "Access Burst Indication (fn=%d iq toa=%f)\n", fn, bi->toa); + rc = gsm_ab_ind_process(as, bi, data, &toa); + if (rc < 0) + goto exit; - gsm_ab_ind_process(as, bi, data, &toa); toa += bi->toa; - trx_data_ind(as->trx, fn, 0, data, toa, 0); + LOGP(DL1C, LOGL_INFO, "Access Burst Indication (fn=%d iq toa=%f)\n", fn, toa); + + trx_data_ind(as->trx, fn, 0, data, toa, 0); exit: msgb_free(msg); |