Appendixb - Functional Operation; Timing; Ground Fault Detect; H2Tu-C-388 List 3E Block Diagram - ADC HiGain H2TU-C-388 Technical Practice

LTPH-TP-1001-02, Issue 2
A
PPENDIX
ADC's HDSL2 technology provides full-duplex services at standard T1 rates over copper wires between an
H2TU-C and an H2TU-R, which comprise one HiGain HDSL2 system. HiGain HDSL2 systems use Overlapped
Pulse Amplitude Modulation (PAM) Transmission with Interlocking Spectra (OPTIS) transceiver systems to
establish full-duplex, 1.552 kbps data channels between the H2TU-C-388 List 3E and a remotely located
H2TU-R.
Figure 32 shows a block diagram of the H2TU-C-388 List 3E. The H2TU-C-388 List 3E receives a 1.544 Mbps
DSX-1 data stream from the DSX-1 digital cross connect interface. The H2TU-C contains a DS1 frame
synchronizer controlled by an 8-bit microprocessor that determines the type of framing on the DS1 stream and
synchronizes to it. The H2TU-C recognizes Superframe (SF), including D4, or Extended Superframe (ESF)
framing.
T
IMING
The low loop wander (0.5 UI max) of an H2TU-C, when used with compatible remote units, allows the circuit to
be used in all critical timing applications, including those that are used to transport Stratum 1 timing.
G F
ROUND AULT
The H2TU-C has a Ground Fault Detect (GFD) circuit which detects a ground or a resistive path to ground on any
wire of the HDSL2 loop. This makes the product compliant with the Class A2 requirements of GR-1089.
H2TU-C-388 List 3E
B - F
UNCTIONAL
Figure 32. H2TU-C-388 List 3E Block Diagram
D
ETECT
February 28, 2001
Appendix B - Functional Operation
O
PERATION
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