Nokia RH-47 Series Rf Description And Troubleshooting page 27

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PCS PCS PCS PCS
Dir. Coupler Dir. Coupler Dir. Coupler Dir. Coupler
TX TX TX TX
An An An An
t t t t
S S S S
GSM GSM GSM GSM
wit wit wit wit
ch ch ch ch
TX TX TX TX
DET DET DET DET
The balanced TX IQ baseband signals (TXIOUTP, TXIOUTN, TXQOUTP, TXQOUTN) are pro-
vided by the baseband and are fed to the Mjoelner RF ASIC. The TX path of the Mjoelner
RF ASIC includes mainly two RF modulators for up-conversion of the baseband signals,
one for GSM850 and one for GSM1900. The baseband signal is up-converted with the LO
signal corresponding to the wanted TX channel. Both RF-TX outputs (850MHz and
1900MHz) of the Mjoelner RF ASIC are delivering balanced signals.
The GSM850 output signal of the Mjoelner RF ASIC is fed through the GSM TX SAW
filter (balanced to single ended) and the GSM850 MHz buffer to the GSM input of the
power amplifier (PA).
The GSM1900 output signal of the Mjoelner RF ASIC is fed through the TX balun (T701)
(balanced to single ended) and a 2dB pad to the GSM1900 input of the power amplifier
(PA).
The Dual Band PA has a maximum output power of approx. 35dBm at 850MHz and
33dBm at 1900MHz. DC-power supply is delivered directly from the battery through an
RF choke L850.
The RF output power is controlled by the power control loop. From the output of the PA
both signals are fed through a dual directional coupler (one of the power control loop
components) to the antenna switch.
Issue 1 05/04
Company Confidential
Figure 6: Transmitter signal paths
VANTL / VANTH
3 3 3 3
VB_DET VB_DET VB_DET VB_DET
VTXLOL VTXLOL VTXLOL VTXLOL
VTXLOH VTXLOH VTXLOH VTXLOH
VTXBH VTXBH VTXBH VTXBH
VTXBL VTXBL VTXBL VTXBL
PCN/PCS PCN/PCS PCN/PCS PCS
OUTHP OUTHP OUTHP OUTHP
Balun Balun Balun Balun
OUTHM OUTHM OUTHM OUTHM
PA PA PA PA
VTX VTX VTX VTX
SAW SAW SAW SAW
Buffer Buffer Buffer Buffer
OUTLP OUTLP OUTLP OUTLP
OUTLM OUTLM OUTLM OUTLM
GSM850 GSM850 GSM850 GSM850
DET DET DET DET
PW- PW- PW- PW-
PLFB1 PLFB1 PLFB1 PLFB1
loop loop loop loop
PLFB2 PLFB2 PLFB2 PLFB2
filter filter filter filter
VPCH/VPCL VPCH/VPCL VPCH/VPCL VPCH/VPCL
VBATTRF VBATTRF VBATTRF VBATTRF
Copyright © 2004 Nokia Corporation
Company Confidential
7 - RF Description and Troubleshooting
VDDDIG VDDDIG VDDDIG VDDDIG VDDDIG VDDDIG
RF RF RF RF RF RF
Controls Controls Controls Controls Controls Controls
1/2 1/2 1/2 1/2 1/2 1/2
VDDRXBB VDDRXBB VDDRXBB VDDRXBB
RF RF RF RF RF RF
Controls Controls Controls Controls Controls Controls
2 2 2 2 2 2
Open Open Open Open Open Open
collector collector collector collector collector collector
Open Open Open Open Open Open
collector collector collector collector collector collector
PWC PWC PWC PWC PWC PWC
V V V V
TX TX TX TX TX TX TX TX
D D D D
P P P P C C C C
DT DT DT DT
2 2 2 2
X X X X
Supply Supply Supply Supply
filter filter filter filter
VT VT VT VT
X X X X
VR2 VR2 VR2 VR2
TXP TXP TXP TXP TXC TXC TXC TXC
RH-47
1/4 1/4 1/4 1/4 1/4 1/4
2 2 2 2 2 2
2 2 2 2 2 2 2 2 2 2 2 2
Mjølner Mjølner Mjølner Mjølner
2 2 2 2 2 2 2 2
TX TX TX TX
TX TX TX TX
Q Q Q Q
IP/ IP/ IP/ IP/
P/ P/ P/ P/
TX TX TX TX
TX TX TX TX
IM IM IM IM
Q Q Q Q
M M M M
Page 27