Tait TB9100, Инструкция по установке и эксплуатации

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102 Technical Description TB9100 Installation and Operation Manual
© Tait Electronics Limited May 2006
Output Paths
The following sections describe how the output paths from the voter to the
four reciter interfaces process their signals.
To the Transmitter
(Digital P25)
Figure 8.9 shows the signal path from the voter to the RF interface for a
digital P25 call.
The winning signal is processed as follows.
1. The voter switches the signal to the P25 modem.
2. The P25 modem adds forward error correction to the IMBE packets.
3. The Modulator/Demodulator circuitry converts the audio frequency
to the required RF frequency (VHF or UHF).
Figure 8.9 Path from voter to transmitter (digital P25 mode)
Packet
Switch
ADC ADC
ADC
Voter
P25
Modem
Mod/
Demod
IMBE
Enc/Dec
G.711
Enc/Dec
FM Audio
Process
RTP
RF
Interface
Control Panel
Speaker/Microphone
Digital
Network
Analog Line
IMBE G.711
IMBE
IMBE/G.711 IMBE/G.711
Digital
Board DSP
Network
Board RISC
Network
Board DSP
IMBE
Dec*
Buffer Buffer