User's Manual

APPLICANT: MOTOROLA EQUIPMENT TYPE: ABZ89FC4823
User / Operational Manual
Functional Description / Operation of Modules (Draft)
EXHIBIT D1-6
Custom Backend Receiver IC Circuitry
The custom backend Receiver IC provides additional amplification, filtering, and a second downconversion. The
second IF signal is converted to a digital signal, and output via either a differential or single-ended driver to the
digital signal processor (DSP) in the SCM.
Memory Circuitry
The memory circuitry consists of an Electrically Erasable Programmable Read-Only Memory (EEPROM), located
in the Receiver. The SCM performs memory read and write operations via the SPI bus. The RX Front-End Filter
tuning calibration is stored in the EEPROM. Therefore, no field tuning is ever required for the Receiver.
Analog to Digital (ADC) Converter Metering Circuitry
Analog signals from points throughout the Receiver are applied to the ADC converter. These analog signals are
converted to digital signals and then sent to the SCM, via the Serial Peripheral Interface (SPI) lines, upon request
of the SCM.
Communications with Station Control Module
Data communications between the Receiver and the Station Control Module microprocessor (μP) is performed via
a Serial Peripheral Interface (SPI) bus. This bus allows the SCM μP to send data to the synthesizer PLL IC (to
select frequency) and to read the ADC Converter IC.
ADC Converter Circuitry
Analog signals from various strategic operating points throughout the Receiver board are fed to an ADC converter,
which converts them to a digital signal and, upon request by the Station Control Module, outputs the signal to the
Station Control Module via the Serial Peripheral Interface (SPI) bus.