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Atec Anritsu-MG3690B User Manual

Page 11

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11

TRACE A: Ch1 8PSK Meas Time

1.5

-1.5

-1.9607643757

1.96078437567

I - Q

300

M

/div

MG3700A

MG3690B

Carrier Frequency = 38.000 GHz

RF

IF

LO

IF Up-Conversion Application and Setup

IF Up-Conversion (Option 7)

Option 7 adds an internal mixer that can be used for the generic up-conversion of

an IF signal. The mixer’s RF, LO, and IF ports are made available at the rear panel

of the MG3690B, via three female K-Connectors. The typical application will feed the

MG3690B microwave output, which can be moved to the rear panel via option 9K,

to the mixer’s LO port. An external IF signal will be fed to the mixer’s IF port. The

new up-converted signal will be available at the mixer’s RF port.

The IF Up-Conversion option is particularly useful to create a microwave frequency

IQ-modulated signal. Lower frequency IQ-modulated RF sources are readily

available, such as the Anritsu MG3681A. Option 7’s IF input can be used to feed in

an IQ-modulated signal from an MG3681A, up-converting it to as high as 40 GHz

with an MG3694B. A typical setup is shown below.

User-Defined Modulation Waveform Software (Option 10)

An external software package provides the ability to download user-defined

waveforms into the internal LF Generator’s (Option 27) memory. The MG3690B

provides as standard with the LF Generator sinusoidal, square-wave, triangle,

positive ramp, Gaussian noise, and uniform noise waveforms.
Two look-up tables of 65,536 points can be used to generate two pseudo-random

waveforms, one for amplitude modulation and the other for frequency or phase

modulation. The download files are simple space-delimited text files containing

integer numbers between 0 and 4095, where 0 corresponds to the minimum

modulation level and 4095 the maximum.
In addition to the capability of downloading custom waveforms, the software offers

a virtual instrument modulation panel. Custom modulation setups with user

waveforms can be stored for future use. For IFF signal simulation, the internal

generators can be synchronized. They can also be disconnected from the internal

modulators, making the low frequency waveforms available at the rear panel for

external purposes.

Scan Modulation (Option 20)

Option 20 adds a microwave linearly controlled attenuator to provide deep AM

capability. This modulator is inserted outside the leveling loop but before the

optional step alternator. It is switched in and out of the RF path. Scan modulation

is driven externally only.
One application of this feature is storing an antenna pattern wave form in memory

and using it to feed the external input to the scan modulator, Option 20.

Mixer Type

Double Balanced

RF, LO Range

1 to 40 GHz

IF Range

DC to 700 MHz

Conversion Loss

10 dB Typical

Max Power into any Port

30 dBm

Isolation, RF to LO

23 dB

LO Drive Level (recommended)

+10 to +13 dBm

Input P

1 dB

+3 dBm Typical

Frequency Range

2 to 18 GHz

Attenuation Range

0 to 60 dB

Flatness/Accuracy

±1.5 dB/±1.5 dB, 0 to 40 dB

±3 dB/±2 dB, 40 to 60 dB

Step Response

< 1 µs

Sensitivity

–10 dB/V

Modulation Bandwidth

20 kHz (small signal)

5 kHz (large signal)

Insertion Loss

< 6 dB (when engaged)

Input

Rear Panel BNC connector

High Impedance