Wlan Tx Description; Gps Interface - Nokia RX-44 Service Manual

RX-44
System Module
The EM chip also integrates power-on reset circuitry and level-shifters for RF front-end GaAs switches.
Host interface is provided by a flexible serial interface (SPI) supporting clock frequency upto 60 MHz. The
system uses 19.2 or 38.4 MHz reference clock from the cellular system as the reference.
RF5924 Front-End Module (FEM) implements amplification of the transmit signal to required power levels.
FEM is connected to VBAT and it has integrated b/g power amplifier, power detector, RX balun, and TX filtering.
Also, it is capable of switching between WLAN RX, WLAN TX and BTH RX/TX operations. .
Synthesizer
The PLL synthesizer with VCO is integrated into RFIC, only the loop filter is needed outside the RFIC.
Antenna
WLAN/BTH has a common antenna and is located in decoration cover. Antenna is shown in picture 23.

WLAN TX description

Transmitter characteristics
The transmitter consists of:
• final frequency IQ-modulators
• power amplifier, for the lower and upper bands separately
• power control loop.
The IQ-modulator is integrated in STLC4560, as well as the operational amplifiers of the power control loop.
The power amplifier is located in a single module with a power detector.
Type
LO frequency range
Output power
Gain control range

GPS interface

The device includes an inbuilt GPS receiver and it works as a stand-alone positioning device. The antenna is
located on the top left corner of the product.
The GPS system is connected to OMAP2420 ASIC.
Issue 1
Item
COMPANY CONFIDENTIAL
Copyright © 2007 Nokia. All rights reserved.
Direct conversion
4824...4944 MHz
802.11b:
17 dBm
802.11g:
13/15/ dBm
60 dB
Values
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