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6816985H01-B
August 16, 2007
900MHz Overall Characteristics:
Vocoder Circuitry Overview
2.5-3
The digital back-end IC (ABACUS-III) consists of the following:
• an amplifier
• the second mixer
• an IF analog-to-digital converter
• a baseband down-converter, and
• a 18 MHz synthesis circuit to provide a sampling clock to the circuitry. The second LO is
generated by discrete components external to the IC. The output of the ABACUS-III IC is a
current-driven digital bit stream.
The transmitter consists of an RF driver IC and a final stage power amplifier. The RF driver IC gets
an injection signal from the VCO. Transmit power is controlled by a power-control IC that monitors
the output of a directional coupler and adjusts the PA control voltages correspondingly. The signal
passes through a RX/TX switch that uses PIN diodes to automatically provide an appropriate
interface to transmit or receive signals.
2.5.6 Vocoder Circuitry Overview
In the VOCON circuitry, the digital-signal processor (DSP) supports IC digital filters, discriminates the
signal, and passes it to the DSP. The DSP decodes the information in the signal and identifies the
following destination for the signal:
• For a voice signal, the DSP routes the digital voice data to the Coder-Decoder (CODEC) for
conversion to an analog signal. The CODEC then presents the signal to the audio pre-amplifier
and audio power amplifier (integrated into the MAKO IC), which drives the speaker.
• For signaling information, the DSP decodes the message and passes it to the microcontroller
unit.
Содержание ASTRO MT 1500
Страница 4: ...iv Table of Contents August 16 2007 6816985H01 B Notes ...
Страница 30: ...August 16 2007 6816985H01 B 2 1 4 VHF Overall Characteristics Vocoder Circuitry Overview Notes ...
Страница 34: ...August 16 2007 6816985H01 B 2 2 4 UHF1 Overall Characteristics Vocoder Circuitry Overview Notes ...
Страница 38: ...August 16 2007 6816985H01 B 2 3 4 UHF2 Overall Characteristics Vocoder Circuitry Overview Notes ...
Страница 42: ...August 16 2007 6816985H01 B 2 4 4 700 800 MHz Overall Characteristics Vocoder Circuitry Overview Notes ...
Страница 46: ...August 16 2007 6816985H01 B 2 5 4 900MHz Overall Characteristics Vocoder Circuitry Overview Notes ...
Страница 140: ...August 16 2007 6816985H01 B 4 4 20 700 800 MHz Detailed Theories of Operation VOCON Functional Blocks Notes ...
Страница 164: ...August 16 2007 6816985H01 B 5 6 Troubleshooting Procedures Operational Error Codes Notes ...
Страница 188: ...August 16 2007 6816985H01 B 6 1 24 VHF Troubleshooting Charts Secure Hardware Failure Notes ...
Страница 212: ...August 16 2007 6816985H01 B 6 2 24 UHF1 Troubleshooting Charts Secure Hardware Failure Notes ...
Страница 236: ...August 16 2007 6816985H01 B 6 3 24 UHF2 Troubleshooting Charts Secure Hardware Failure Notes ...
Страница 260: ...August 16 2007 6816985H01 B 6 4 24 700 800 MHz Troubleshooting Charts Secure Hardware Failure Notes ...
Страница 284: ...August 16 2007 6816985H01 B 6 5 24 900 MHz Troubleshooting Charts Secure Hardware Failure Notes ...
Страница 296: ...August 16 2007 6816985H01 B 7 1 12 VHF Troubleshooting Waveforms PP7 TX LO 7 1 11PP7 TX LO Probe point TP299 ...
Страница 301: ...6816985H01 B August 16 2007 VHF Troubleshooting Waveforms TP13 Mod In 7 1 17 7 1 16TP13 Mod In Test point TP36 ...
Страница 324: ...August 16 2007 6816985H01 B 7 1 40 VHF Troubleshooting Waveforms PP33 SPI Data 7 1 39PP33 SPI Data Probe Point R802 ...
Страница 325: ...6816985H01 B August 16 2007 VHF Troubleshooting Waveforms PP34 SPI CLK 7 1 41 7 1 40PP34 SPI CLK Probe Point R803 ...
Страница 342: ...August 16 2007 6816985H01 B 7 2 12 UHF1 Troubleshooting Waveforms PP7 TX LO 7 2 11PP7 TX LO Probe point TP299 ...
Страница 347: ...6816985H01 B August 16 2007 UHF1 Troubleshooting Waveforms TP13 Mod In 7 2 17 7 2 16TP13 Mod In Test point TP36 ...
Страница 371: ...6816985H01 B August 16 2007 UHF1 Troubleshooting Waveforms PP33 SPI Data 7 2 41 7 2 39PP33 SPI Data Probe Point R802 ...
Страница 372: ...August 16 2007 6816985H01 B 7 2 42 UHF1 Troubleshooting Waveforms PP34 SPI CLK 7 2 40PP34 SPI CLK Probe Point R803 ...
Страница 378: ...August 16 2007 6816985H01 B 7 2 48 UHF1 Troubleshooting Waveforms TP39 RX SSI Frame Sync Notes ...
Страница 390: ...August 16 2007 6816985H01 B 7 3 12 UHF2 Troubleshooting Waveforms PP7 TX LO 7 3 11PP7 TX LO Probe point TP299 ...
Страница 395: ...6816985H01 B August 16 2007 UHF2 Troubleshooting Waveforms TP13 Mod In 7 3 17 7 3 16TP13 Mod In Test point TP36 ...
Страница 418: ...August 16 2007 6816985H01 B 7 3 40 UHF2 Troubleshooting Waveforms PP33 SPI Data 7 3 39PP33 SPI Data Probe Point R802 ...
Страница 419: ...6816985H01 B August 16 2007 UHF2 Troubleshooting Waveforms PP34 SPI CLK 7 3 41 7 3 40PP34 SPI CLK Probe Point R803 ...
Страница 486: ...August 16 2007 6816985H01 B 7 5 12 Troubleshooting Waveforms PP7 TX LO 7 5 11PP7 TX LO Probe point Shield Tx_INJ ...
Страница 492: ...August 16 2007 6816985H01 B 7 5 18 Troubleshooting Waveforms TP13 Mod In 7 5 17TP13 Mod In Test point TP203 ...
Страница 501: ...6816985H01 B August 16 2007 Troubleshooting Waveforms PP22 Analog 5V 7 5 27 7 5 26PP22 Analog 5V Probe point U500 pin 5 ...
Страница 517: ...6816985H01 B August 16 2007 Troubleshooting Waveforms PP33 SPI Data 7 5 43 7 5 42PP33 SPI Data Probe Point R802 ...
Страница 518: ...August 16 2007 6816985H01 B 7 5 44 Troubleshooting Waveforms PP34 SPI CLK 7 5 43PP34 SPI CLK Probe Point R803 ...
Страница 521: ...6816985H01 B August 16 2007 Troubleshooting Waveforms TP37 RX SSI Data 7 5 47 7 5 46TP37 RX SSI Data Test Point TP403 ...
Страница 522: ...August 16 2007 6816985H01 B 7 5 48 Troubleshooting Waveforms TP38 RX SSI Clock 7 5 47TP38 RX SSI Clock Test Point TP404 ...
Страница 710: ...9 2 40 UHF1 Schematics Board Overlays and Parts Lists August 16 2007 6816985H01 B Notes ...
Страница 806: ...9 5 32 900MHz Schematics Board Overlays and Parts Lists August 16 2007 6816985H01 B Notes ...
Страница 816: ...Index 4 August 16 2007 6816985H01 B Notes ...
Страница 817: ......