From b3a2a3e24f44adcc6660d33cc9684a8f24271e2e Mon Sep 17 00:00:00 2001 From: Harald Welte Date: Mon, 27 Jun 2016 18:56:01 +0200 Subject: RACH decoding: Use BER threshold for RACH ghost detection When decoding RACH bursts, we should use a BER threshold in order to help distinguish 'ghost' RACH bursts from real RACH bursts. The theoretical ideal threshold according to some papers is 7 out of 41 bits qhich aquals to Eb/N0 of 0 dB = 0.1707 (17.07%) We add a new 'ber10k' parameter to the RACH indication l1sap primitive (needs separate change for libosmocore), and then fill this value from osmo-bts-{sysmo,lc15,trx,octphy}. The common part above L1SAP then applies the threshold, which can be changed from vty using the "max-ber10k-rach <0-10000>" command available at the BTS node. The unit is BER in 1/10000, i.e. a value of 100 equals 1% bit error rate. Change-Id: Ic41c11f6312a36baa2738547e8dcec80829457f8 --- include/osmo-bts/gsm_data.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/osmo-bts/gsm_data.h b/include/osmo-bts/gsm_data.h index f2574b15..10c9d049 100644 --- a/include/osmo-bts/gsm_data.h +++ b/include/osmo-bts/gsm_data.h @@ -111,6 +111,7 @@ struct gsm_bts_role_bts { float min_qual_rach; /* minimum quality for RACH bursts */ float min_qual_norm; /* minimum quality for normal daata */ + uint16_t max_ber10k_rach; /* Maximum permitted RACH BER in 0.01% */ struct { char *sock_path; -- cgit v1.2.3