Ringing In The Uen - Nortel DMS-100 Series General Description Manual

1-42 DMS-100 ringing overview
Figure 1-30 Timing of audible and power ringing signals - immediate ringing
enabled
Power ring
(LME coded and
superimposed
ringing or LCM
coded ringing)
Power ring (LCE
superimposed
ringing)
Audible ring

Ringing in the UEN

In the UEN, there is no external ringing generator. Iinstead, each line card (line
subgroup) containsa ringing generator. The zero crossings of the ringing
sinusoid are monitored and coordinate several control operations that are
synchronized to the ringing signal. The TDM software can change the state of
the ringing relays at the coder-decoders (CODEC) to the zero crossing.
297-1001-131 Standard 06.01 October 2000
1 ringing cycle
2 s
0 1 2 3 4 5 6 7 8
Power ring
starts
Ring request
Audible ring starts
0 1 2 3 4 5 6 7 8
2 s
1 audible ring back cycle
91011 0 1 2 3 4 5
91011 0 1 2 3 4 5
6 7 8 9 1011
6 7 8 9 1011