Nokia 3105 Servicehandbuch
CCS Technical Documentation
System Module
RH-48
Issue 1 11/2003 Confidential ©
2003 Nokia Corporation
Page 19
The MCU software enters automatically to Local or Test mode at start-up if correspond-
ing resistors are connected.
ing resistors are connected.
Note: Baseband doesn’t wake up automatically when the battery voltage is connected (Normal
mode).
mode).
RF Module
Requirements
RH-48 supports CDMA 800 MHz as described in:
• IS2000-2-A Physical Layer Standard for cdma2000 Spread Spectrum Systems; and
• IS-98D (Draft 4) Recommended Minimum Performance Standard for Spread Spectrum
Mobile Stations.
Antenna
An internal antenna is used.
Transmitter
Figure 8: RF transmitter block diagram
The transmit chain up to the RF driver stage is integrated into one transmit-integrated
circuit called Jedi, with external power amplifiers (PA). The channel spacing is 30 kHz.
circuit called Jedi, with external power amplifiers (PA). The channel spacing is 30 kHz.
All data transmitted on the channel is convolutionally encoded and block-interleaved.
Modulation is 64-ary orthogonal (RC1 and RC2) and direct sequence spread by a quadra-
ture pair of PN sequences at a fixed chip rate. The data is filtered, O-QPSK modulated
and up-converted to the appropriate transmission frequency. RC3 and RC4 use HPSK
modulation at data rates up to 153.6 kBPS (RC3) and 115.2 kBPS (RC4).
Modulation is 64-ary orthogonal (RC1 and RC2) and direct sequence spread by a quadra-
ture pair of PN sequences at a fixed chip rate. The data is filtered, O-QPSK modulated
and up-converted to the appropriate transmission frequency. RC3 and RC4 use HPSK
modulation at data rates up to 153.6 kBPS (RC3) and 115.2 kBPS (RC4).
The baseband I/Q signals are converted to IF frequency in the I/Q modulator by Quadra-
ture mixing. The modulated IF signals go through a variable gain amplifier (IF AGC) and
then are routed to the Cell TX path. The path consists of an upconverter and a variable
ture mixing. The modulated IF signals go through a variable gain amplifier (IF AGC) and
then are routed to the Cell TX path. The path consists of an upconverter and a variable
0º
I
Q
0º
UHF LO
90º
Isolator
Power
Detector
To Baseband
÷2/÷4
90º
VHF LO
90º
0º
90º
0º
Cell RX
Antenna
Duplexer
From
Baseband
0º
I
Q
0º
UHF LO
90º
Isolator
0º
I
Q
0º
UHF LO
90º
Isolator
Power
Detector
To Baseband
÷2/÷4
90º
VHF LO
90º
0º
90º
0º
Cell RX
Antenna
Duplexer
From
Baseband
Power
Detector
Power
Detector
To Baseband
÷2/÷4
90º
VHF LO
90º
0º
90º
0º
Cell RX
Antenna
Duplexer
From
Baseband
÷2/÷4
90º
VHF LO
90º
0º
0º
90º
0º
0º
Cell RX
Antenna
Duplexer
From
Baseband