Alarm Signal Transmission; Dsc Transmit Side; Dsc Receive Side; Ws Transmit Side/Ws Receive Side - NEC PASOLINK Training Course

FUNCTIONAL OPERATION
2.8.1

DSC Transmit Side

2.8.2

DSC Receive Side

2.9

Alarm Signal Transmission

2.10 Wayside Signal Transmission (Optional)
2.10.1 WS Transmit Side
2.10.2 WS Receive Side
2-24
The DSC signal received from DSC IN terminal is applied to level
converter circuit. Here, the DSC signal is converted into 9.6 K transistor-
transistor logic (TTL) level in the level converter and fed to the digital
processing unit (DPU) circuit on the MAIN BOARD. In the DPU circuit,
9.6 K (TTL) signal is converted into 40 kbps (approx.) with 40 kHz
(approx.) clock produced at the MAIN BOARD, and fed to the opposite
station.
The 40 kbps (approx.) extracted from DPU circuit on the MAIN BOARD
is converted into 9.6 K (TTL) signal with 9.6 kHz clock. The 9.6 K (TTL)
signal is converted into 9.6 K DSC signal in the level converter, and fed to
the DSC OUT terminal.
With optional ALM INTFC card, two channels cluster alarm transmission
provides for external/internal alarm signal extension.
The wayside (WS) signal transmission is performed in the WS INTFC
section.
The 2.048 Mbps bipolar signal applied through the WS IN terminal is fed
to the bilopar-unipolar converter (B-U CONV) circuit, where it is
converted into a NRZ unipolar signal. NRZ unipolar signal is code-
converted by the HDB-3 decoder. The code-converted 2.048 Mbps WS
data signal is fed to the MAIN BOARD together with the clock.
The process of RX side is the reverse of the process of the TX side. The
2.048 Mbps WS data signal and clock are applied to the HDB-3 encoder.
In the HDB-3 encoder, 2.048 Mbps WS signal is code-converted and fed
to unipolar-bipolar converter (U-B CONV). The 2.048 Mbps unipolar
data signal is converted into the 2.048 Mbps bipolar data stream and fed to
the WS OUT terminal.
ROI-S04488