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Field Service Ver. 7.0 Jan. 2009
F. Phase 3 .....Training of the main channel equalizer
• Band division full-duplex method
• Transmission and reception of Phase 3 signals (S, , PP, TRN) are executed by using
parameter values which are determined by exchanging INF Oh. (symbol rate, carrier fre-
quency, pre-emphasis filter and transmission level)
Calling
Called
• The speed of the following signals (Phase 3) are determined by INFOh. (The following
signals are used in the main channel in the half-duplex procedure.)
S
:Signal which sends alternately 0 point and a point which rotated 0 point coun-
terclockwise by 90 degrees
:Signal which sends alternately a point which rotated 0 point counterclockwise
by 180 degrees and a point which rotated 0 point counterclockwise by 270
degrees
PP
:Special signal which is sent from a remote station for adjusting an equalizer
TRN
:Training signal. (Symbol rate and duration are determined in INFOh.)
(1) Control channel signal
• The following signals are used for establishing the control channel or re-synchronization
and retrain. (peculiar to half-duplex procedure)
Modulation method:
1200 / 2400bps QAM modulation (600 ± 0.01 symbols / sec). However, training
and synchronous signals are 1200bps.
Calling modem: Carrier (=1200Hz ± 0.01% (level = set value))
Called modem: Carrier (=2400Hz ± 0.01% (level = set value-1dB))
+Guard tone
Sh
:Signal which sends alternately 0 point and a point which rotated 0 point coun-
terclockwise by 90 degrees (the same as S)
:Signal which sends alternately a point which rotated 0 point counterclockwise
by 180 degrees and a point which rotated 0 point counterclockwise by 270
degrees (the same as S)
AC
:Signal which send alternately 0 point and a point which rotated 0 point by 180
degrees
PPh
:Special signal which is sent from a remote station for adjusting an equalizer
(used when the initial of the control channel and re-synchronization are exe-
cuted)
ALT
:Signal which scrambled alternate signals of 0 and 1 (1200bps)
MPh
:Binary signal used for exchanging parameters of the modulation method when
data is actually sent and received by using the main channel
(Both type 0 and type 1 (type 0+pre-recording coefficient) must be received.)
(When type 0 is received, pre-recording coefficient is considered to be 0 and
never functions.)
E
: "1", binary of 20 bit, which represents the beginning of user data transmission
on the control channel
Y104784-2
Phase3
Control channel start-up procedure
32T
16T or more
PPh
ALT
S
S
PP
TRN
–
120T or less
128T 16T 288T
70
5ms
PPh
ALT
32T or less
Between 16T and 120T
(=1800Hz ± 0.01% (level = set value-7dB))
Service Manual
2. COMMUNICATION CONTROL
* : Symbol interval
MPh
MPh
E
control channel data
MPh
MPh
E
control channel data
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