Nokia 9000i - 1 St TX Buffer; 2 Nd TX Buffer; TX Interstage Filters

After Sales
Technical Documentation
RAE/RAK–1N
RF
Page 3– 20
Amendment 1 04/97
1st TX buffer
The TX buffer is a bipolar transistor amplifier. It amplifies the TX signal
coming from the upconversion mixer.
Table 12. 1st TX amplifier specification
Parameter Minimum Typical /
Nominal
Maximum Unit / Notes
Operating freq. range GSM
PCN
890
1710
915
1785
MHz
MHz
Supply voltage 4.25 4.5 4.8 V
Current consumption
GSM / PCN
4.5 5.0 mA
Insertion gain GSM
PCN
11
10
12
11
13
12
dB
dB
Input VSWR (Zo=50 ohms) 2.0 Matched to the mixer
Output VSWR (Zo=50 ohms) 2.0
TX interstage filters
The TX filters reject the spurious signals generated in the upconversion
mixer. They also reject the local, image and IF signal leakage and RX
band noise.
2nd TX buffer
The TX buffer is a bipolar transistor amplifier. It amplifies the TX signal
coming from the first interstage filter.
Table 13. 2nd TX amplifier specification
Parameter Minimum Typical /
Nominal
Maximum Unit / Notes
Operating freq. range GSM
PCN
890
1710
915
1785
MHz
MHz
Supply voltage 4.25 4.5 4.8 V
Current consumption GSM
PCN
9.0
16.0
10.0
17.0
mA
mA
Insertion gain GSM
PCN
11
15
12
16
13
17
dB
dB
Output power (Zo=50 ohms)
GSM
PCN
0
2
3
7
dBm
dBm
Input VSWR (Zo=50 ohms) 2.0
Output VSWR (Zo=50 ohms) 2.0