Anritsu MG3710A Installation and operating instructions

Application Note
MG3710A
Vector Signal Generator
Optimization Technique using
Two-signal Combine Function
MG3710A
Vector Signal Generator

1 MG3710A-E-F-4-(1.00)
Contents
1. Introduction.............................................................................................................................................................2
1.1. Technical Terms...............................................................................................................................................2
2. Two-signal Combine Function ..............................................................................................................................3
2.1. Advantages of Two-Signal Combine Function .............................................................................................4
2.2. Linearity ............................................................................................................................................................5
2.3. Combining Different Wireless Systems.........................................................................................................5
3. Optimization Technique........................................................................................................................................6
3.1. Avoiding Carrier Leak and Image...................................................................................................................6
3.1.1. Carrier Leak and Image ............................................................................................................................6
3.1.2 Effect on Wanted Signal............................................................................................................................6
3.1.3. Improvement and Prevention Methods ..................................................................................................8
3.2. Reducing Two-Signal Third Order Distortion................................................................................................9
3.2.1. Two-Signal Third Order Distortion..........................................................................................................9
3.2.2. Reduction Method...................................................................................................................................10
3.3. Improvement of In-band Frequency Characteristics..................................................................................11
3.3.1. Improvement Method..............................................................................................................................11
4. Other Consideration Points.................................................................................................................................12
4.1. Phase Noise....................................................................................................................................................12
4.2. AM Noise.........................................................................................................................................................13
4.3. Floor Noise .....................................................................................................................................................14
5. Practical Examples...............................................................................................................................................15
5.1. ARIB STD-T61Adjacent Channel Selectivity ...............................................................................................15
5.1.1. Structure of Measurement System using MG3710A ...........................................................................15
5.1.2. Setting Procedure...................................................................................................................................17
6. Summary................................................................................................................................................................21

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1. Introduction
This document introduces the two-signal combine function of the MG3710A Vector Signal Generator (MG3710A
hereafter) and explains an optimized technique for measurement using this function.
1.1. Technical Terms
This section explains the technical terms used in this document.
Baseband frequency LO frequency
A vector signal generator is composed of a baseband block for generating the I/Q signal and an RF block for
converting the I/Q signal to an RF signal for output. The RF block uses a quadrature modulator to convert the I/Q
signal to the RF signal. In this article, the frequency of the I/Q signal generated by the baseband block is called the
baseband frequency, while the frequency at conversion to the RF signal is called the LO frequency (Figure 1).
Figure 1. Baseband Frequency and LO Frequency
Measured Value
Performance not warranted. Data actually measured by randomly selected measuring instruments.
Baseband Frequency
Power
Baseband
Block
RF Block
I/Q Signal
RF Signal
Vector Signal
Generator
0 Hz
1 MHz
RF
Frequency
Power
1 GHz
1.001 GHz
Frequency Conversion
(LO Frequency
= 1 GHz)

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2. Two-signal Combine Function
A general vector signal generator outputs one type of waveform pattern from one RF output. Using the two-signal
combine function, the MG3710A can combine the waveform selected in Memory A with the waveform selected in
Memory B for simultaneous output. In addition, the level ratio, frequency offset and time offset of each selected
waveform can be set easily from the panel (Figure 2).
Figure 2. Example of Two-signal Combine Setting Display
The setting range and resolution of the parameters can be specified as follows:
Level ratio (A/B Ratio)
Setting range: –80 to 80 dB
Resolution: 0.01 dB
Frequency offset (Freq Offset A/B)
Setting range: –100 to +100 MHz
Resolution: 1 Hz
Time offset (Start Offset)
Setting range: 0 to (whichever is smaller of Memory-B waveform data points –1 or 9,999,99)
Resolution: 1 sample (sampling rate of Memory-B waveform)
Adding the following option enables the two-signal combine function.
MG3710A-048 Combination of Baseband Signal for 1stRF
(MG3710A-078 Combination of Baseband Signal for 2ndRF)

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Figure 3 shows an example of the output-signal spectrum using the two-signal combine function.
Figure 3. Example of Two-signal Combine Function Spectrum
2.1. Advantages of Two-Signal Combine Function
Evaluation of Rx characteristics such as Adjacent Channel Selectivity (ACS), Intermodulation Characteristics (IM),
etc., requires measurements of characteristics when an interference wave is added to the wanted wave.
In a conventional signal generator, one unit can only output either the wanted or the interference wave so a test
requiring the wanted wave and the interference wave requires two signal generators as well as a coupler to
combine the two signals. Additionally, the work required to set the level ratio of the wanted and interference waves
is quite difficult (Figure 4).
Using the all-in-one MG3710A two-signal combine function outputs both the wanted and interference signals and
offers the following advantages (Figure 4).
Advantage 1: Only one SG required
Advantage 2: External coupler not required
Advantage 3: Level ratio adjustment not required
Figure 4. Example of Rx Characteristics Test Setup
When using two signals simultaneously like this, the MG3710A Two-Signal Combine Function supports easy setup
of the test environment.
Conventional general signal generator
Signal
Generator 1
Signal
Generator 2
Coupling
circuit
DUT
Using
MG3710A
DUT
Wanted signal
Interference signal
Wanted + interference
signal
Memory-A Output Waveform
Memory-B Output Waveform

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2.2. Linearity
Because the MG3710ATwo-Signal Combine Function synthesizes the signal digitally, the combined signal is output
with an accurate level ratio.
Figure 5 shows an example of the MG3710A Two-Signal Combine Function level ratio settings and linearity error,
indicating that the two-signal combine output has high linearity.
Figure 5. Linearity Error (Measurement Value)
In Figure 5, two-signal combination was performed to output a CW signal at MG3710A baseband
frequencies of 0 Hz (signal A) and 20 MHz (signal B). The level of signal A was fixed while the level ratio
of signal A/B was varied from 0 to 80 dB to measure the linearity error of signal B.
2.3. Combining Different Wireless Systems
3GPP Release 9 defines Multi-Standard Radio (MSR) base stations capable of sending and receiving signals for
multiple radio systems simultaneously. MSR requires the ability to handle different systems such as LTE, W-CDMA,
GSM/EDGE, TD-SCDMA, etc., simultaneously. Irrespective of MSR, each of the different waveform data for these
types of systems also has a different sampling rate. Creating different sampling rate signals as one waveform data
requires complex signal processing such as rate conversion and data cycle adjustment. In addition, the size of the
synthesized waveform data tends to be much too large due not a little to the inadequate recovery performance from
the signal generator.
Although the MG3700A Vector Signal Generator has a built-in two-signal combine function for synthesizing two
signals at the baseband, it is still necessary to match the sampling rates of the waveform data in advance. This
requires waveform data rate conversion, causing problems with the increase in the size of the waveform data after
conversion.
To solve this problem, the MG3710A has a rate matching function (Figure 6) to output the combined two signals
with each sampling rate maintained even for the same signals with different sampling rates.
Figure 6. MG3710A Baseband Block
Using the MG3710A, a combined signal for wireless systems with different sampling rates can be output easily
without requiring any special procedures.
*Refer to Creation of Multi-Standard Radio Signals using MG3710A Two-Signal Combine Function
(MG3710A-J-F-1) for a description of how to create MSR signals.
Memory A
Memory B
Rate
matching
Frequency
offset
adjustment
Frequency
offset
adjustment
Gain
adjustment
Gain
adjustment
DAC

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3. Optimization Technique
This section explains the MG3710A optimization technique for obtaining the best performance when using the two-
signal combine function.
3.1. Avoiding Carrier Leak and Image
3.1.1. Carrier Leak and Image
A signal generator generates the RF signal by synthesizing the baseband signal and LO signal at the quadrature
modulator, but spurious components called carrier leak an image are also generated at this time. Carrier leak is
generated at the position where the baseband frequency is 0 Hz. Image is generated at the –fc(Hz) position when
the output signal baseband frequency is fc(Hz).
Figure 7. Carrier Leak and Image
Carrier leak is caused mainly by the DC offset of the baseband signal input to the quadrature modulator as well as
by DC offset generated within the quadrature modulator. Image is caused mainly by orthogonality error of the
quadrature modulator, amplitude error of the I/Q signal, and skew error.
3.1.2 Effect on Wanted Signal
When the carrier leak and image spurious signals are at the same position as the wanted waveform, they can have
deleterious effects on the signal quality such as the modulation accuracy and level accuracy.
Figure 8 plots the distribution of the Continuous Wave (CW) predicted by the carrier leak and image for the center
frequency of the required wave (W-CDMA) and the change in the Error Vector Magnitude when the CW level is
changed.
The x-axis is the ratio of the CW output and the W-CDMA signal output level.
Figure 8. EVM Changes due to Spurious (Measurement Value)
We can see that the EVM degrades as the carrier leak becomes larger. (This is in the case for W-CDMA, but the
results are sometimes different for other modulation methods.)
Baseband frequency
Power
Output waveform
fc
-fc
Image
0
Carrier leak

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Moreover, when the CW is at the same frequency as the carrier leak/image, these two signals become stronger
when at the same phase, and weaker when out of phase, causing a change in the level error at CW due to this
phase relationship (Figure 9).
Figure 9. Phase Relationship and Synthesized Wave
Figure 10 plots the CW signal carrier leak (image) level ratio against the calculated level error of the CW signal.
Figure 10.Change in Level Error due to Carrier Leak and Image
The modulation accuracy and level accuracy are adversely impacted by this overlap between the CW, the
modulation wave, and the position of the carrier leak/image generation. When using the two signal combine
function, it is necessary to note that there may be a larger effect when the two signal level ratio is large, because
the lower level signal may approach the level of the carrier leak/image.
Time
Time
Time
Time
(a) In Phase
(b) Out of Phase
Wanted signal (CW signal)
Carrier leak or image
Synthesized Wave

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3.1.3. Improvement and Prevention Methods
The MG3710A can automatically adjust the quadrature modulator using the I/Q Calibration function.
(Key operation: I/Q key –[F5] I/Q Calibration –[F1] Execute)
Using this function, auto-adjustment is performed to minimize the carrier leak and image.
Figure 11 shows the carrier leak and image frequency plots after using this function. The plots show the measured
values at input of a CW signal with a 10-MHz frequency offset.
(a) Carrier leak (b) Image
Figure 11. MG3710A Carrier Leak and Image Frequency Characteristics (after I/Q Calibration) (Measured Values)
Although the I/Q Calibration function minimizes the carrier leak and image, it does not completely remove them.
When the carrier leak/image reduction effect using the I/Q Calibration function is inadequate, adjusting the
frequency offset so that the output waveform and carrier leak/image do not overlap can prevent the effect.
The following considers an example when outputting a modulation wave and CW wave with a 50-kHz gap. Figure
12 (a) shows the spectrum when the modulation wave is positioned at the baseband frequency 0 Hz and CW is
positioned at 50 kHz, and the frequency setting is 800 MHz. (The blue line is the trace when modulation is off.)
With this arrangement, the modulation accuracy is degraded because the carrier leak tends to overlap the
modulation wave.
Figure 12 (b) shows the spectrum when the modulation wave is positioned at the baseband frequency –50 kHz,
CW is positioned at 0 kHz and the frequency setting is 800.05 MHz. (The blue line is the trace when modulation is
off.)
With this arrangement, the modulation and level accuracies are not degraded because the carrier leak/image do
not overlap the modulation wave and the combined two signals can be output. The carrier leak does not overlap
the CW as shown in the example in Figure 12 (b), and the level ratio of the carrier leak to CW is 65 dB, so the
impact on the CW level error is less than 0.005 dB and can be practically ignored. (Refer to section 3.1.2 Effect on
Wanted Signal for a description of the carrier leak on the wanted signal.)
(a) Carrier Leak overlapping modulation wave (b) Carrier Leak not overlapping modulation wave
Figure 12.Preventing Carrier Leak and Image
When the level of the wanted wave is small relative to the interference wave in this type of wanted wave
(modulation wave) + interference wave (CW or modulation wave), setting the optimum baseband frequency can be
an effective method for minimizing error.
Carrier leak
Image

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The optimum baseband frequency is usually found as follows.
When frequency difference of two signals is fo [Hz]:
Wanted waveform baseband frequency: –fo [Hz] or fo [Hz]
Interference waveform baseband frequency: 0 [Hz]
Although the carrier leak overlaps the interference wave, when the carrier leak level is sufficiently low compared to
the interference wave level, it can be ignored because the impact on the interference wave is small (0 Effect on
Wanted Signal.)
Using the MG3710A, the baseband frequency for Memory A and Memory B can be set at Frequency Offset A and
Frequency Offset B, respectively.
(Key operation: Mode key –[F2]ARB Setup –More key –[F2]Freq Offset A/[F3]Freq Offset B)
Note the following points when setting the baseband frequency to a value other than 0 Hz.
Level error occurs due to the in-band frequency characteristics. Refer to section 3.3 In-band Frequency
Characteristics for a description of the effect of in-band frequency characteristics.
3.2. Reducing Two-Signal Third Order Distortion
3.2.1. Two-Signal Third Order Distortion
Distortion components caused by intermodulation between two or more signals or their harmonics is called
intermodulation distortion, and there is an extremely large number of types, depending on the signal order. The
distortion with the largest impact when using the two-signal combine function is called Two-Signal Third Order
Distortion.
Two-Signal Third Order Distortion is observed at the two locations defined as 2fc1 –fc2 and 2fc2 –fc1 [Hz] when the
baseband frequencies are fc1 [Hz], and fc2 [Hz], respectively (Figure 13).
Figure 13.Two-Signal Third Order Distortion
Two-signal third order distortion is generated by three main factors: baseband block quantization error, quadrature
modulator non-linearity, and RF block non-linearity.
Like carrier leak/image, two-signal third order distortion degrades the modulation wave and CW signal quality and
level accuracy. Care is required when using the two-signal combine function with two signals with close levels.
Baseband frequency
Power
Output waveform A
CW signal
2fc1-fc2
fc1
fc2
2fc2-fc1
2 Signal Third Order Distortion
0
Output waveform B
CW signal

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3.2.2. Reduction Method
When the distortion level ratio of two signals does not change even when changing the SG Level setting (Key
operation: Level key), the two-signal third order distortion is dominated either by quantization error in the baseband
block or by non-linearity effects of the quadrature modulator. The generated distortion amount can be optimized by
adjusting the level diagram of the digital block(s) using the RMS Value Tuning function.
(Key operation): Mode key –More key –[F6]RMS Value Tuning)
When the RMS Value Tuning setting is large, the baseband block gain becomes large and has the effect of
reducing quantization error. However, when the effect of the quadrature modulator non-linearity is large, this
distortion becomes large.
On the other hand, when the RMS Value Tuning setting is small, the baseband block gain becomes small and the
quantization error becomes large while the quadrature amplifier non-linearity effect conversely becomes small.
The optimum value is tuned to minimize the generated distortion because the amount of distortion is determined by
the simultaneous action of each. (Sometimes, this type of simple action does not occur due to the phase
relationships of each distortion characteristic.)
Note the following points when tuning with the RMS Value Tuning function.
If the RMS Value Tuning setting is too large, sometimes waveform data clipping occurs in the baseband block. If
clipping occurs, BBDAC is displayed in the MG3710A warning field and large spurious occurs. Select the RMS
Value Tuning setting to prevent clipping (Figure 14, Figure 15).
Sometimes UNLVL is displayed in the Amplitude display when adjusting the RMS Value Tuning setting. This
indicates that the output level is out of the guaranteed range. If UNLVL is displayed, it is necessary to confirm that
the correct level is output using a power sensor, etc. (Figure 15).
RMS Value Tuning has an effect on the floor noise. Refer to section 4.3 Floor Noise for a description of the effect
on floor noise.
(a) Without clipping (b) With clipping
Figure 14. Spectrum With and Without Clipping Effect
Figure 15.BBDAC and UNLVL
BBDAC Display
UNLVL Display

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3.3. Improvement of In-band Frequency Characteristics
Although a vector signal generator can output a modulation signal for any band in the modulation band, the in-band
level accuracy has non-even frequency characteristics (in-band frequency characteristics). As a result, when
outputting a signal with added offset frequency, it is necessary to consider the in-band frequency characteristics.
When adding offset frequency or when handling wideband modulation signals, note that the level error becomes
larger further from the 0 Hz baseband frequency.
3.3.1. Improvement Method
The MG3710A has an Internal Channel Correction function for correcting the in-band frequency characteristics.
Figures 16 and 17 show the sample values for the in-band frequency characteristics when this function is Off and
On, respectively.
Figure 16.In-band Frequency Characteristics (Internal Channel Correction = Off) (Measurement Value)
Figure 17.In-band Frequency Characteristics (Internal Channel Correction = On) (Measurement Value)

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4. Other Consideration Points
This section explains other precautionary points when using a signal generator, excluding the two-signal combine
function.
4.1. Phase Noise
The ideal CW signal is a simple spectrum. However, in actual use, the ideal oscillator does not exist and the signal
is always frequency modulated by slight noise. This effect is observed as the spectrum widens and is called phase
noise.
Phase noise becomes larger approaching the CW oscillation frequency, and smaller further away. When the two-
signal frequency gap is narrow and the level difference is small, it is important to note that the signal with the
smaller level suffers degraded SNR due to the phase noise (Figure 18).
Figure 18.Phase Noise
Using the MG3710A Phase Noise Optimize function optimizes the phase noise by selecting from the near and far
phase noise characteristics. Switching the Phase Noise setting value performs optimization according to the offset
frequency to be used.
(Key operation: Frequency key –More key –[F1]Phase Noise Opt.)
Figures 19 and 20 show the phase noise characteristics at modulation output.
Figure 19.MG3710A Phase Noise Characteristics (Phase Noise Opt.: <200 kHz) (Measurement Value)
Frequency
Power Spectrum Density
Output waveform B
CW signal
Output waveform A
Modulation signal
Phase noise
Large impact of phase
noise with narrow two
signal frequency gap and
large level difference

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Figure 20.MG3710A Phase Noise Characteristics (Phase Noise Opt.: >300 kHz) (Measurement Value)
4.2. AM Noise
In contrast to phase noise generated by noise in the phase direction, AM noise occurs as the spectrum widens due
to noise in the amplitude direction. AM noise is mainly generated by the ALC (auto level control) circuit and
becomes larger closer to the CW oscillation frequency, and smaller further away, similar to phase noise. When the
two-signal frequency gap is narrow and the level difference is large, it is important to note that the signal with the
smaller level suffers degraded SNR due to the AM noise (Figure 21).
Figure 21.AM Noise
Figure 22 shows the AM noise characteristics of the MG3710A. CW means an unmodulated signal and ATT Hold =
Off; Mod means a modulated or unmodulated signal and ATT Hold = On.
Figure 22.MG3710A AM Noise Characteristics (Measurement Value)
Frequency
Power Spectrum Density
Output waveform B
CW signal
Output waveform A
Modulation signal
AM noise
Large impact of AM noise
with narrow two signal
frequency gap and large
level difference

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4.3. Floor Noise
A signal generator has its own floor noise determined by the SNR of the signal generator itself. Consequently,
when the two signal ratio becomes larger, the output waveform with the smaller level of the two signals is closer to
the floor noise of the signal generator. It is important to note that when the two-signal level difference is large, the
SNR of the signal with the smaller level becomes degraded due to floor noise (Figure 23).
Figure 23.Floor Noise
The floor noise is determined by the combined SNR of the signal generator baseband and RF blocks. In the
MG3710A, at modulation output the SNR of the baseband block always dominates.
The baseband block level diagram can be optimized for each application by adjustment using the RMS Value
Tuning function.
(Key operation: Mode key –More key –[F6]RMS Value Tuning)
Increasing the RMS Value Tuning setting increases the baseband block gain, having the effect of reducing the floor
noise. Conversely, reducing the RMS Value Tuning setting lowers the baseband block gain and increases the floor
noise (Figure 24).
Figure 24.Floor Noise Optimization by RMS Value Tuning
Note the following precaution points when adjusting using the RMS Value Tuning function.
If the RMS Value Tuning setting is too large, sometimes waveform data clipping occurs in the baseband block. If
clipping occurs, BBDAC is displayed in the MG3710A warning field and large spurious occurs. Select the RMS
Value Tuning setting to prevent clipping (Figure 14, Figure 15).
Sometimes UNLVL is displayed in the Amplitude display when adjusting the RMS Value Tuning setting. This
indicates that the output level is out of the guaranteed range. If UNLVL is displayed, it is necessary to confirm that
the correct level is output using a power sensor, etc. (Figure 15).
Sometimes the SNR of the RF block is dominant, depending on the selected waveform and level. In this case, the
floor noise does not change even if the RMS Value Tuning setting is changed.
RMS Value Tuning has an impact on two-signal third order distortion.
Refer to section 3.2 Reducing Two-Signal Third Order Distortion for a description of the effect on two-signal third
order distortion.
Frequency
Power Spectrum Density
Output waveform B
CW signal
Output waveform A
Modulation signal
Phase noise
AM noise
Floor noise
Large impact of floor noise
with large 2 signal level
difference
Frequency
Power Spectrum Density
Output waveform B
CW signal
Output waveform A
Modulation signal
Phase noise
Floor noise
Increasing RMS Value Tuning
setting decreases floor noise

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5. Practical Examples
This section gives some practical examples for ARIB STD-T61Adjacent Channel Selectivity measurements, and
explains the MG3710A setting procedure in detail.
However, the measurement values in these examples are measurement data for randomly selected instruments
and are not guaranteed values.
5.1. ARIB STD-T61Adjacent Channel Selectivity
The system for measuring ARIB STD-T61 Adjacent Channel Selectivity is described below.
Figure 25.Adjacent Channel Selectivity Measurement System
Table 1 lists the names for each output waveform package and pattern.
Table 1. Adjacent Channel Selectivity Measurement Usage Pattern
Pattern
Signal Contents
Package Name
Pattern Name
Pattern 1
ARIB STD-T61 Test Signal 1
ARIB_STD-T61
(MX370002A)
UpDownLink
Pattern 2
ARIB STD-T61 Test Signal 2
ARIB_STD-T61
(MX370002A)
PN15
*The waveform pattern file must be provided separately.
5.1.1. Structure of Measurement System using MG3710A
Figure 26 shows the setup using the MG3710A instead of two pattern signal generators and two high-frequency
signal generators.
Figure 26. Adjacent Channel Selectivity Measurement System (using MG3710A)
The MG3710A settings for two-signal combined output are:
ARIB STD-T61 Test Signal 1 in Memory A and level setting of –52 dBm
ARIB STD-T61 Test Signal 2 in Memory B and level setting of –10 dBm
Wanted waveform (Memory A) frequency of 400 MHz
The measuring instrument specifications for the ARIB STD-T61 standard are as follows:
High-frequency signal generator 1 and 2
Frequency Standard frequency range
Stability within ±5×10-8
ACLR ±6.25kHz Separation: <–63 dB
Modulation accuracy EVM(rms) within 3% (recommended)
Consider each of the following points:
Frequency
Since the ARIB STD-T61 wireless frequency band is 400 MHz and 150 MHz, the MG3710A supports either band
as an option.
High-
freq signal
generator 1
Pattern
generator 1
Pattern
generator 2
High-freq
signal
generator 2
Integrator/
coupler
Attenuator
Power
measurement
equipment
DUT Bit error
clock
Integrator
Attenuator
ower
measurement
equipment
DUT Bit error
clock
MG3710A

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Stability
To assure compliance with the standard, use either the Opt-001/101 (Rubidium Reference Oscillator) or the Opt-
002/102 (High-Stability Reference Oscillator).
ACLR
The MG3710A measures the actual value of the adjacent channel leakage power using a spectrum analyzer.
Figure 27 shows an example of the measurement results. The top leakage power is –73.44 dB, and the bottom is
–73.60 dB, satisfying the standards.
Figure 27.ARIB-STD T61 ACLR (Measurement Value)
Modulation accuracy
To prevent degraded modulation accuracy caused by carrier leak/image effects, the interference wave is positioned
at the 0 Hz baseband frequency and the wanted wave is positioned at baseband frequency ±6.25 kHz.
Figure 28 shows an example of modulation measurement at this time. (The measurement result is only when the
wanted wave is output.)
It is clear that the EVM(rms) of 0.48% satisfies the standard.
Figure 28.ARIB-STD T61 Modulation Accuracy (Measurement Value)
The above shows that the MG3710A meets the required conditions for satisfying the standard.

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5.1.2. Setting Procedure
(1) Load the waveform pattern
Open the waveform pattern load screen.
(Key operation: Load key)
Load the ARIB STD-T61 test signal 1 into Memory A.
(Key operation: Set [F8] To Memory to A, select “ARIB_STD-T61(MX370002A)”for –Package and
“UpDownLink”for Pattern, and press [F6] Load Pattern.)
Load the ARIB STD-T61 test signal 2 into Memory B.
(Key operation: Set [F8] To Memory to B, select “ARIB_STD-T61(MX370002A)”for –Package and “PN15”for
Pattern, and press [F6] Load Pattern.)
Figure 29.Load Screen
Note the following point when loading the waveform pattern.
Pre-load waveform patterns into the MG3710A. Refer to the MG3700A/MG3710A Vector Signal Generator
Instruction Manual for how to create waveform patterns and copy them to the MG3710A.

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(2) Select the waveform pattern.
Set the Combination Mode to Edit to allow selection of each waveform pattern for Memory A and Memory B.
(Operation: Set Mode key –[F2] Combination Mode to Edit.)
Select the ARIB STD-T61 test signal 1 for Memory A.
(Key operation: Press the Select key and set [F8] On Memory to A, select “ARIB_STD-T61(MX370002A)”for
Package, “UpDownLink”for Pattern, and press [F6] Select.)
Select ARIB STD-T61 test signal 2 for Memory B.
(Key operation: Press the Select key and set [F8] On Memory to B, select “ARIB_STD-T61(MX370002A)”for
Package, “PN15”for Pattern, and press [F6] Select.)
Figure 30.Select Screen
(3) Set the levels.
Set the output level for Memory A to –52 dBm.
(Key operation: Set Mode key –[F3] ARB Setup –[F2] Level A to –52 dBm.)
Set the Memory B output to On.
(Key operation: Set [F3] Output B to On.)
Set the output level for Memory A to –10 dBm.
(Key operation: Set [F4] Level B to –10 dBm.)

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(4) Set the frequency offset.
Set Center Signal to A. By doing this the frequency display at the top of the MG3710A screen is referenced to
Memory A. The Memory-B value is fixed at the LO frequency position.
(Key operation: Set Mode key –[F3] ARB Setup –Mode key –[F4] Center Signal to A.)
Set the frequency offset of Memory A to 6.25 kHz.
(Key operation: Set Mode key –[F3] ARB Setup –Mode key –[F1] Freq Offset to 6.25 kHz.)
(5) Set the output
Set the RF frequency for memory A to 400 MHz.
(Key operation: Press the Freq key to set to 400 MHz.)
Set Modulation to On.
(Key operation: Press the Mod On/Off key to set it to On.)
Set the RF Output to On.
(Key operation: Press the RF Output On/Off key to set it to On.)
Figure 31 shows an example of the MG3710A setting screen. The output signal spectrum is shown in Figure 32.
Figure 31.Example of MG3710A Setting Screen
Hint
The Center Signal setting determines which of Memory A or Memory B becomes the reference value for the
frequency display at the top of the screen.
When Center Signal is A, Memory A becomes the reference for the frequency at the top of the screen and
Memory B is fixed at the LO frequency position.
When Center Signal is B, Memory B becomes the reference for the frequency at the top of the screen and the
Memory B side is fixed at the LO frequency position.
When Center Signal is Baseband DC, the frequency at the top of the screen displays the LO frequency.
Memory A and Memory B are set to baseband Frequency Offset A and Frequency Offset B, respectively.