![](http://datasheet.mmic.net.cn/150000/EVB3020A_datasheet_5004872/EVB3020A_15.png)
Advance Data Sheet
December 1999
W3020 GSM Multiband RF Transceiver
Lucent Technologies Inc.
15
Modulator
The modulator uses an indirect I/Q modulator architecture that is ideal for multiband operation. The IF
modulation improves EVM effects due to improved carrier feedthrough. The series transmit IF filters allow
improved wideband noise, which enables duplexer removal. The I/Q modulator requires no amplitude or phase
calibration to achieve high phase accuracy. The modulator can be altered between GSM900 transmit mode (TX
IF = 270 MHz) and GSM1800/1900 transmit mode (TX IF = 180 MHz) by the band bit setting in the TR register.
Table 8. Modulator Performance
VDD = 2.7 V; TA = 25 °C ± 3 °C. IQ common mode = 1.6 V; input differential signal = 1.0 Vp-p.
Parameter
Min
Typ
Max
Unit
I/Q Signal Path Bandwidth
—
450
—
kHz
I/Q Input Resistance to Ground
25
—
k
I/Q Input Capacitance to Ground
—
10
pF
I/Q Input Resistance (differential)
10
—
k
I/Q Input Capacitance (differential)
—
10
pF
I/Q Common-mode Range
1.5
—
VDD – 1.05
V
I/Q Input Differential Signal for Max Output
0.8
1
1.2
Vp-p
RF Output Band:
GSM900
GSM1800
GSM1900
880
1710
1850
—
915
1785
1910
MHz
Output Power:
GSM900 (LO1 at 1167 MHz)
GSM1800 (LO1 at 1567 MHz)
–4.5
–4
0
6
dBm
Powerup Time*
—
4
s
RMS Phase Accuracy
:
GSM900
GSM1800
—
2.0
2.5
—
°rms
GMSK Modulation Spectrum (max) (offset from carrier):
100 kHz
@30 kHz RBW
—
0.5
dBc
200 kHz
—
–30
dBc
250 kHz
—
–33
dBc
400 kHz
—
–60
dBc
1.8 MHz—3.0 MHz
@100 kHz RBW
—
–65
dBc
3.0 MHz—6.0 MHz
—
–65
dBc
>6.0 MHz
—
–73
dBc
Wideband Noise IF Modulator
GSM900:
|f – f0|
≥ 10 MHz
—
–140
—
dBc/Hz
|f – f0|
≥ 20 MHz (PM)
—
–140
—
dBc/Hz
GSM1800:
|f – f0|
≥ 20 MHz (PM)
—
–140
—
dBc/Hz
Wideband Noise RF Mixer (See Figure 6.):
GSM900:
|f – f0|
≥ 10 MHz
—
–154
—
dBc/Hz
|f – f0|
≥ 20 MHz (PM)
—
–154
—
dBc/Hz
GSM1800:
|f – f0|
≥ 20 MHz (PM)
—
–153
—
dBc/Hz
* From the programming latch going high to power available at RF output, Including TX IF filter group delay.
Including contributions from LO1, LO2, and modulator.