1 Scope
2 References
3 Definitions
4 Abbreviations
5 Digital modem
6 Analogue modem
6.1 Data signalling rates
6.2 Symbol rate
6.3 Scrambler
6.4 Transmitter
6.4.1 Modulus encoder
6.4.2 Precoder and prefilter
6.4.3 Inverse map
6.4.4 Convolutional encoder
7
Interchange circuits
7.1 List of interchange circuits
7.2 Asynchronous character-mode interfacing
8 Signals and sequences
8.1 Full Phase 1
8.2 Short Phase 1 signals and sequences for the analogue modem
8.2.1
QC1a
8.2.2 QC2a
8.2.3 QCA1a
8.2.4 QCA2a
8.2.5 TONEq
8.3 Short Phase 1 signals and sequences for the digital modem
8.3.1
ANSpcm
8.3.2 QC1d
8.3.3 QC2d
8.3.4 QCA1d
8.3.5 QCA2d
8.3.6 QTS
8.4 Full and short Phase 2 signals and sequences
8.4.1 INFO information
bits
8.5 Phase 3 signals for the analogue modem
8.5.1
CPt
8.5.2 E1u
8.5.3 MD
8.5.4 Ja
8.5.5 Ru
8.5.6 Su
8.5.7 TRN1u
8.6 Phase 3,
signals for the digital modem
8.6.1
DIL
8.6.2 Jd
8.6.3 Jp
8.6.4 Jp´
8.6.5 Ri
8.6.6 SCR
8.6.7 Sd
8.6.8 TRN1d
8.7 Phase 4, Rate Renegotiation and Fast Parameter Exchange signals
for the analogue modem
8.7.1
B1u
8.7.2 E2u
8.7.3 CPu
8.7.4 RM
8.7.5 SUVu
8.7.6 TRN2u
8.7.7 FB1u
8.8 Phase 4, Rate Renegotiation and Fast Parameter Exchange signals
for the digital modem
8.8.1 B1d
8.8.2 Ed
8.8.3 CPd
8.8.4 R
8.8.5 SUVd
8.8.6 TRN2d
8.9 Modem-on-hold
8.9.1 RT
8.9.2 MH sequences
9 Operating
procedures
9.1 Full Phase 1 – Network interaction
9.2 Short Phase 1 – Network interaction
9.2.1 Call modem is
analogue modem
9.2.2 Call modem is
digital modem
9.2.3 Answer
modem is analogue modem
9.2.4 Answer modem is
digital modem
9.2.5 ODP/ADP bypass
9.3 Full Phase 2 – Probing/ranging
9.3.1 ODP/ADP bypass
9.4 Short Phase 2 – Ranging
9.4.1
Digital modem
9.4.2 Analogue modem
9.5 Phase 3 – Equalizer and echo canceller training and digital
impairment learning
9.5.1
Digital modem
9.5.2 Analogue
modem
9.6 Phase 4 – Final training
9.6.1
Digital modem
9.6.2 Analogue modem
9.7 Retrains
9.7.1 Digital modem
9.7.2 Analogue modem
9.8 Rate renegotiation
9.8.1
Digital modem
9.8.2 Analogue modem
9.9 Fast parameter exchange
9.9.1
Digital modem
9.9.2 Analogue modem
9.10 Modem‑on‑hold
9.10.1 Transmission of
MH sequences
9.10.2 Modem‑on‑hold
transactions
9.11 Cleardown
10 Testing
facilities