User Guide

RF description

Receiver (RX)

An analogue signal is received by the phone's antenna. The signal is converted to a digital signal and is then

transferred further to the baseband (eg. to the earpiece).

The receiver functions are implemented in the RF ASIC.

Signals with different frequencies take different paths, therefore being handled by different components.

Transmitter (TX)

The digital baseband signal (eg. from the microphone) is converted to an analogue signal, which is then

amplified and transmitted from the antenna. The frequency of this signal can be tuned to match the

bandwidth of the system in use (eg. GSM900).

The transmitter functions are implemented in the RF ASIC.

RM-378; RM-379

System Module

Page 5 –16 COMPANY CONFIDENTIAL Issue 1