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.
Bluetooth
Bluetooth provides a fully digital link for communication between a master unit (the phone) and one or more
slave units (e.g. a wireless headset). Data and control interface for a low power RF module is provided by the
module.
RM-561
System Module
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