SVP HDT-02, User Manual

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HDT-02_H.264 High Definition Digital Camera Transmitter
MANUAL V9.9 145
Chapter 7: Block Diagram
7.1 Introduction
In this chapter, the block diagram of the HDT-02 Transmitter is explained.
This diagram has several parts related to the HDT-02 internal performance
which are shown in blocks with different inputs and outputs.
In the first part, the outputs from the video encoder, Audio 1 encoder and
Audio 2 encoder go to the multiplexer to obtain one common output signal.
Then, the signal passes through the encryption system to make the message
unintelligible at a receiver not equipped with an appropriately configured
decryption device. In the same way, the ASI transport stream can be
scrambled in BISS 1 or BISS E, with a Session Word, or encrypted with
AES128 and AES256. This is an ultimate solution for reliable and
interoperable protection of the communication. As it is explained in the
manual, if NONE option is selected the signal will not be encrypted.
Once the signal has passed the encryption block, it passes through the DVB-
T/T2/S/S2 modulator. In this part, the signal is modulated according to the
needed requirements and a digital signal is obtained. The next step is to go
to the DAC converter to obtain an analogue signal. There are two digital to
analog converters blocks. The first one provides a 70 MHz output and the
other one goes to the Quadrature Modulator which is a general technique of
modulating employing a VCO & PLL system. Thanks to the VCO & PLL block,
the system frequency can be configured, and then, in the output of the
Quadrature Modulator block, the RF signal is obtained.
The next block consists of a variable attenuator that controls the output
power. Then a splitter is required, which distributes the signal to four different
amplifier blocks. In this way, there are four different outputs, one for DVB-
S/S2 L-Band and three for DVB-T/T2 1-6,4 GHz depending on the user
necessities. The 10 MHz oscillator is used for the synchronization of the BUC
and it can be enabled or disabled.
At the bottom of the diagram, there is a FPGA Controller, which is responsible
for controlling all the system. This block also controls the Remote Control
(RTC), the Power Amplifier (PA), the temperature and the voltage. It has an
USB and Ethernet control connection too.