Broadcast Microwave Services Inc TCIIAD-2 Manual De Usuario
2
To simplify installation, only a single coaxial cable is required to interconnect the IDU to the ODU; DC
power, 70MHz IF and telemetry signals are all multiplexed onto this single cable. The system also supports
legacy cable systems that feed DC power on separate conductors.
power, 70MHz IF and telemetry signals are all multiplexed onto this single cable. The system also supports
legacy cable systems that feed DC power on separate conductors.
The indoor unit features a menu driven front panel display (vacuum fluorescent) that is used to configure
the equipment and monitor its performance. The system is also designed to support remote control by 3
the equipment and monitor its performance. The system is also designed to support remote control by 3
rd
party equipment using either web based or simple RS232 protocol.
The outdoor RF unit (ODU) is designed to be mounted outdoors adjacent to the antenna. The ODU
translates the 70MHz IF signal from the IDU (exciter) to the desired operating frequency and amplifies the
signal to the desired level. The RF unit employs automatic level control circuits that keep the system
operating optimally and eliminate the need for any user adjustments.
translates the 70MHz IF signal from the IDU (exciter) to the desired operating frequency and amplifies the
signal to the desired level. The RF unit employs automatic level control circuits that keep the system
operating optimally and eliminate the need for any user adjustments.
The ODU uses a common signal path for both Analog (FM) and digital (COFDM) operation. Performance
is automatically optimized for both methods. BMS transmitters feature superior COFDM performance that
is adequate to support split channel operation in a 12MHz channel (see BMS white paper).
is automatically optimized for both methods. BMS transmitters feature superior COFDM performance that
is adequate to support split channel operation in a 12MHz channel (see BMS white paper).
The ODU provides signals to control an antenna relay and feed polarity. Additional contact closures are
also provided for user specific applications.
also provided for user specific applications.
A more detailed description follows:
Indoor Unit
A simplified block diagram of the IDU is shown below:
Composite Video
Front panel
(VFD display)
Power Supply
120/220 VAC
Ext 70 MHz input
(BNC)
splitter
Ext 70 MHz output
(BNC)
Cable
Telemetry
Controller
N-plexer
10bT
Prog
Sub-cxr
Prog
Sub-cxr
Video
LPF
70MHz
FM Mod
FM Modulator
Analog Audio 1
RS232
Remote
Management
DAC
COFDM
Modulator
MPEG-2
Encoder
Encoder
Audio
DAC
Video
DAC
SDI
Interface
SDI Video
(with/without embedded Audio)
ASI
ASI
RX
ASI
TX
Analog Audio 2
TruckCoder II (Indoor Unit)
SMPTE
Bars /
audio
tone
Pre-
emph
RS232
BNC (75 ohm)
50 or 75 ohms
COFDM Modulator
To ODU
Figure 2 TCII IDU (Indoor Unit) Block Diagram
The FM modulator is designed to accept analog audio and video inputs. Support for 2 audio channels is
provided via frequency programmable sub carriers that ride above the video signal. Programmable audio
sub-carriers facilitate compatibility with existing receivers. The video signal path includes a delay
equalized filter and pre-emphasis network. The deviation is user configurable to support operation in either
a 17 MHz or 12 MHz channel allowing Analog operation to continue after the channel plan transition is
provided via frequency programmable sub carriers that ride above the video signal. Programmable audio
sub-carriers facilitate compatibility with existing receivers. The video signal path includes a delay
equalized filter and pre-emphasis network. The deviation is user configurable to support operation in either
a 17 MHz or 12 MHz channel allowing Analog operation to continue after the channel plan transition is