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fixeria gerrit-no-reply at lists.osmocom.orgfixeria has uploaded this change for review. ( https://gerrit.osmocom.org/c/osmo-bts/+/23823 ) Change subject: osmo-bts-trx: remove outdated TRXD protocol documentation ...................................................................... osmo-bts-trx: remove outdated TRXD protocol documentation We do have TRXC/TRXD documentation in osmo-gsm-manuals repository. This big comment is out of sync with what we have in the manuals, so let's better remove it to avoid maintaining docs in several places. Change-Id: Ibfcefcbb5f30fe9b6c691578a93e6fedd5644b30 Related: SYS#4895, OS#4941, OS#4006 --- M src/osmo-bts-trx/trx_if.c 1 file changed, 1 insertion(+), 118 deletions(-) git pull ssh://gerrit.osmocom.org:29418/osmo-bts refs/changes/23/23823/1 diff --git a/src/osmo-bts-trx/trx_if.c b/src/osmo-bts-trx/trx_if.c index bec6a5a..495de92 100644 --- a/src/osmo-bts-trx/trx_if.c +++ b/src/osmo-bts-trx/trx_if.c @@ -916,124 +916,7 @@ return buf; } -/* Parse TRXD message from transceiver, compose an UL burst indication. - * - * This message contains a demodulated Uplink burst with fixed-size - * header preceding the burst bits. The header consists of the common - * and message specific part. - * - * +---------------+-----------------+------------+ - * | common header | specific header | burst bits | - * +---------------+-----------------+------------+ - * - * Common header is the same as for Downlink message: - * - * +-----------------+----------------+-------------------+ - * | VER (1/2 octet) | TN (1/2 octet) | FN (4 octets, BE) | - * +-----------------+----------------+-------------------+ - * - * and among with TDMA parameters, contains the version indicator: - * - * +-----------------+------------------------+ - * | 7 6 5 4 3 2 1 0 | bit numbers | - * +-----------------+------------------------+ - * | X X X X . . . . | PDU version (0..15) | - * +-----------------+------------------------+ - * | . . . . . X X X | TDMA TN (0..7) | - * +-----------------+------------------------+ - * | . . . . X . . . | RESERVED (0) | - * +-----------------+------------------------+ - * - * which is encoded in 4 MSB bits of the first octet, which used to be - * zero-initialized due to the value range of TDMA TN. Therefore, the - * old header format has implicit version 0x00. - * - * The message specific header has the following structure: - * - * == Version 0x00 - * - * +------+-----+--------------------+ - * | RSSI | ToA | soft-bits (254..0) | - * +------+-----+--------------------+ - * - * == Version 0x01 - * - * +------+-----+-----+-----+--------------------+ - * | RSSI | ToA | MTS | C/I | soft-bits (254..0) | - * +------+-----+-----+-----+--------------------+ - * - * where: - * - * - RSSI (1 octet) - Received Signal Strength Indication - * encoded without the negative sign. - * - ToA (2 octets) - Timing of Arrival in units of 1/256 - * of symbol (big endian). - * - MTS (1 octet) - Modulation and Training Sequence info. - * - C/I (2 octets) - Carrier-to-Interference ratio (big endian). - * - * == Coding of MTS: Modulation and Training Sequence info - * - * 3GPP TS 45.002 version 15.1.0 defines several modulation types, - * and a few sets of training sequences for each type. The most - * common are GMSK and 8-PSK (which is used in EDGE). - * - * +-----------------+---------------------------------------+ - * | 7 6 5 4 3 2 1 0 | bit numbers (value range) | - * +-----------------+---------------------------------------+ - * | . . . . . X X X | Training Sequence Code (0..7) | - * +-----------------+---------------------------------------+ - * | . X X X X . . . | Modulation, TS set number (see below) | - * +-----------------+---------------------------------------+ - * | X . . . . . . . | IDLE / nope frame indication (0 or 1) | - * +-----------------+---------------------------------------+ - * - * The bit number 7 (MSB) is set to high when either nothing has been - * detected, or during IDLE frames, so we can deliver noise levels, - * and avoid clock gaps on the L1 side. Other bits are ignored, - * and should be set to low (0) in this case. L16 shall be set to 0x00. - * - * == Coding of modulation and TS set number - * - * GMSK has 4 sets of training sequences (see tables 5.2.3a-d), - * while 8-PSK (see tables 5.2.3f-g) and the others have 2 sets. - * Access and Synchronization bursts also have several synch. - * sequences. - * - * +-----------------+---------------------------------------+ - * | 7 6 5 4 3 2 1 0 | bit numbers (value range) | - * +-----------------+---------------------------------------+ - * | . 0 0 X X . . . | GMSK, 4 TS sets (0..3) | - * +-----------------+---------------------------------------+ - * | . 0 1 0 X . . . | 8-PSK, 2 TS sets (0..1) | - * +-----------------+---------------------------------------+ - * | . 0 1 1 X . . . | AQPSK, 2 TS sets (0..1) | - * +-----------------+---------------------------------------+ - * | . 1 0 0 X . . . | 16QAM, 2 TS sets (0..1) | - * +-----------------+---------------------------------------+ - * | . 1 0 1 X . . . | 32QAM, 2 TS sets (0..1) | - * +-----------------+---------------------------------------+ - * | . 1 1 1 X . . . | RESERVED (0) | - * +-----------------+---------------------------------------+ - * - * NOTE: we only support GMSK and 8-PSK. - * - * == C/I: Carrier-to-Interference ratio - * - * The C/I value can be computed from the training sequence of each - * burst, where we can compare the "ideal" training sequence with - * the actual training sequence and then express that in centiBels. - * - * == Coding of the burst bits - * - * Unlike to be transmitted bursts, the received bursts are designated - * using the soft-bits notation, so the receiver can indicate its - * assurance from 0 to -127 that a given bit is 1, and from 0 to +127 - * that a given bit is 0. - * - * Each soft-bit (-127..127) of the burst is encoded as an unsigned - * value in range (254..0) respectively using the constant shift. - * - */ +/* Parse TRXD message from transceiver, compose an UL burst indication. */ static int trx_data_read_cb(struct osmo_fd *ofd, unsigned int what) { struct trx_l1h *l1h = ofd->data; -- To view, visit https://gerrit.osmocom.org/c/osmo-bts/+/23823 To unsubscribe, or for help writing mail filters, visit https://gerrit.osmocom.org/settings Gerrit-Project: osmo-bts Gerrit-Branch: master Gerrit-Change-Id: Ibfcefcbb5f30fe9b6c691578a93e6fedd5644b30 Gerrit-Change-Number: 23823 Gerrit-PatchSet: 1 Gerrit-Owner: fixeria <vyanitskiy at sysmocom.de> Gerrit-MessageType: newchange -------------- next part -------------- An HTML attachment was scrubbed... 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