User manual

DTS Broadcast PDH Microwave Digital Radio User Manual
-12-
The QPSK IF signal with 70MHz carrier received by ODU will be demodulated required frame
data. And the frame data will be demultiplexed by frame-diplexer to EOW signal, Auxiliary Data, CPU
site-to-site communication messages and service data. The EOW signal is sent to phone interface, the
Auxiliary Data is sent to Auxiliary Data interface, the CPU messages is sent to CPU for management,
and the service data send to service plug-in card.
The CPU in IDU monitors the device running, and communicates with NMS.
The DC-DC module in IDU is feed by -48V and supports 3.3V, 5V and 1.5V for system
The IDU-ODU communicating module supports communication between IDU and ODU. The
IDU can configure frequency and monitors status of ODU by this module.
Figure 2-16 Block diagram of the IDU
The modulator of QPSK modem in IDU has functions list below: See Figure 2-17.
Convolutive Coder with 7/8 puncture rate.
Digital interpolation filters
I/Q modulater with 310MHz IF signal.
IF signal amplifier.
PLL module with 310MHz for modulate