SMIQ
Supplement
1125.55610.12-10-
A
E-1
Supplement to Manual SMIQ
Special Features of HD Model
VECTOR MOD menu with model SMIQ03HD:
IQ FILTER
Selection between filter off and a 2.5 MHz, 5 MHz, 7.5 MHz or 10 MHz lowpass filter in the base-
band. The filters suppress noise in the baseband, which improves adjacent channel power
(ACP) with W-CDMA. The filter frequency response is automatically compensated with DIGITAL
MOD and DIGITAL STD in the MCOD mode, so that the error vector magnitude (EVM)
deteriorates only slightly. If the VECTOR MOD mode is active and AMIQ with WinIQSIM used
as a source, the frequency response is compensated by WinIQSIM. For applications requiring a
very low EVM the I/Q filter should always be switched OFF.
OFF
filter off
2.5 MHz
2.5 MHz lowpass filter
5 MHz
5 MHz lowpass filter
7.5 MHz
7.5 MHz lowpass filter
10 MHz
10 MHz lowpass filter
IEC/IEEE-bus commands
:SOUR:DM:IQ:FILT:STAT ON|OFF
:SOUR:DM:IQ:FILT:FREQ 2.5MHZ
HIGH ACLR W-CDMA signals with a very high adjacent channel power ratio (ACPR) can be generated
in the 3GPP downlink band by means of option SMIQB57 (High ACLR for W-CDMA) in
conjunction with option SMIQB20 (Modulation Coder). Moreover, RF peak levels up to
+30 dBm can be produced thanks to the extremely linear power amplifier.
Note:
Option SMIQB57 can be used only in the 2110 MHz to 2170 MHz 3GPP
downlink band. Although carrier frequencies outside this band can be set, no
specified values exist for such applications.
I/Q modulator
I
Q
WCDMA filter
RF output
G
BP
2110 to 2170MHz
BW 3.84MHz
Power
Amplifier
RF up/down converter
sin
cos
High ACLR option SMIQB57
Fig. 1
High ACLR for W-CDMA