JDS Uniphase JD7105B User manual

1 GSM/GPRS/EDGE SIGNAL ANALYZER
JD7105B Base Station Analyzer
GSM/GPRS/EDGE Signal Analyzer
This GSM/GPRS/EDGE Signal Analyzer function is optional that the JD7105B Base Station Analyzer
offers as the Option 022 for GSM/GPRS/EDGE. It allows the user to check conformity to the 3GPP TS
51.021 Base Station System (BSS) equipment specification: Radio Aspects V8.9.0 (2003-06) and
analyze GSM/EDGE system performance. The GSM//GPRS/EDGE OTAAnalyzer which is the Option
042 can be added to the GSM/GPRS/EDGE Signal Analyzer for Over The Air measurement.
In this Chapter
Using GSM/GPRS/EDGE Signal Analyzer.............................................................................................. 4
Display Overview..................................................................................................................................... 5
Connecting a Cable................................................................................................................................. 7
Direct Connection...................................................................................................................... 7
Indirect Connection................................................................................................................... 7
Over The Air (OTA) ................................................................................................................... 8
Spectrum Analysis Measurement............................................................................................................ 9
Setting Mode............................................................................................................................. 9
Setting Frequency..................................................................................................................... 9
Setting Amplitude.................................................................................................................... 10
Setting Averaging.................................................................................................................... 12
Setting Sweep Mode............................................................................................................... 12
Setting Trace and Display....................................................................................................... 12
Measurement Example........................................................................................................... 13
Using Marker........................................................................................................................... 13
Using Peak Search ................................................................................................................. 15
RF Analysis Measurements................................................................................................................... 16
Setting Mode........................................................................................................................... 16
Setting Frequency................................................................................................................... 16
Setting Amplitude.................................................................................................................... 17
Setting Averaging.................................................................................................................... 19
Setting Sweep Mode............................................................................................................... 19
Setting Trigger Source ............................................................................................................ 19
Channel Power...................................................................................................................................... 21
Measurement Procedure ........................................................................................................ 21
Setting Limit ............................................................................................................................ 22
Measurement Example........................................................................................................... 23
Using Marker........................................................................................................................... 23
Using Peak Search ................................................................................................................. 24
Occupied Bandwidth.............................................................................................................................. 25
Measurement Procedure ........................................................................................................ 25
Setting Limit ............................................................................................................................ 25

GSM/GPRS/EDGE SIGNAL ANALYZER 2
JD7105B Base Station Analyzer
Measurement Example........................................................................................................... 27
Using Marker........................................................................................................................... 27
Using Peak Search ................................................................................................................. 28
Spectrum Emission Mask (SEM)........................................................................................................... 29
Measurement Procedure ........................................................................................................ 29
Setting Limit ............................................................................................................................ 30
Measurement Example........................................................................................................... 31
Using Marker........................................................................................................................... 31
Using Peak Search ................................................................................................................. 32
Spurious Emissions............................................................................................................................... 33
Measurement Procedure ........................................................................................................ 33
Setting Limit ............................................................................................................................ 35
Measurement Example........................................................................................................... 36
Using Marker........................................................................................................................... 36
Using Peak Search ................................................................................................................. 37
Power vs Time Measurements.............................................................................................................. 38
Setting Mode........................................................................................................................... 38
Setting Frequency................................................................................................................... 38
Setting Amplitude.................................................................................................................... 39
Setting Averaging.................................................................................................................... 41
Setting Sweep Mode............................................................................................................... 41
Setting Trigger Source ............................................................................................................ 41
Setting External Clock............................................................................................................. 42
Measurement Procedure ........................................................................................................ 43
Setting Limit ............................................................................................................................ 44
Measurement Example........................................................................................................... 46
Constellation Measurement................................................................................................................... 47
Setting Mode........................................................................................................................... 47
Setting Frequency................................................................................................................... 47
Setting Amplitude.................................................................................................................... 48
Setting Averaging.................................................................................................................... 49
Setting Trace and Display....................................................................................................... 50
Setting Sweep Mode............................................................................................................... 50
Setting Trigger Source ............................................................................................................ 50
Setting External Clock............................................................................................................. 51
Measurement Procedure ........................................................................................................ 52
Setting Limit ............................................................................................................................ 53
Measurement Example........................................................................................................... 56
GSM OTA Measurements...................................................................................................................... 57
Setting Mode........................................................................................................................... 57
Setting Frequency for Channel/Frequency Scanners............................................................. 57
Setting Amplitude.................................................................................................................... 59
Setting Sweep Mode............................................................................................................... 60
Setting Trigger Source ............................................................................................................ 60
Setting External Clock............................................................................................................. 60
GSM OTA Channel Scanner.................................................................................................................. 62
Setting Mode........................................................................................................................... 62
Setting Channel....................................................................................................................... 62
Setting Zoom Position............................................................................................................. 63
Measurement Procedure ........................................................................................................ 63
Measurement Example........................................................................................................... 64
GSM OTA Frequency Scanner.............................................................................................................. 65
Setting Mode........................................................................................................................... 65

3 GSM/GPRS/EDGE SIGNAL ANALYZER
JD7105B Base Station Analyzer
Setting Frequency................................................................................................................... 65
Setting Zoom Position............................................................................................................. 66
Measurement Procedure ........................................................................................................ 66
Measurement Example........................................................................................................... 67
GSM OTA Multipath Profile.................................................................................................................... 68
Setting Mode........................................................................................................................... 68
Measurement Procedure ........................................................................................................ 68
Measurement Example........................................................................................................... 69
GSM OTA Modulation Analyzer............................................................................................................. 71
Setting Mode........................................................................................................................... 71
Measurement Procedure ........................................................................................................ 71
Setting Limit ............................................................................................................................ 72
Measurement Example........................................................................................................... 75
(Rev. 3.0)

GSM/GPRS/EDGE SIGNAL ANALYZER 4
JD7105B Base Station Analyzer
USING GSM/GPRS/EDGE SIGNAL ANALYZER
The Global System for Mobile Communications (GSM) is a digital cellular standard that uses Time
Division Multiple Access (TDMA) multiplexing scheme and Gaussian Minimum Shift Keying (GMSK)
modulation. The Enhanced Data Rates for GSM Evolution (EDGE) is an enhancement to GSM that
promises to deliver true 3G wireless services such as multimedia and other broadband applications. It
uses TDMA and 3π/8 8PSK (phase shift keying) modulation.
The JD7105B performs measurements using the methods and limits as defined in the 3GPP TS
51.021 Base Station System (BSS) equipment specification: Radio Aspects V8.9.0 (2003-06). The
Pass/Fail indictor helps the user to determine base station performance easily.
The JD7105B provides the following analysis tools for GSM/GPRS/EDGE system.
Spectrum Analysis
RF Analysis
Channel Power
Occupied Bandwidth
Spectrum Emission Mask
Spurious Emissions
Power vs Time
Slot
Frame
Constellation
Over The Air (OTA)
Channel Scanner
Frequency Scanner
Multipath Profile
Modulation Analyzer
Auto Measure

5 GSM/GPRS/EDGE SIGNAL ANALYZER
JD7105B Base Station Analyzer
DISPLAY OVERVIEW
Overview of GSM Signal Analyzer Display
①Measurement Mode Information: GSM Signal Analyzer
②Spectrum Windows X and Y Scale or Setting Information: This window shows the most
common settings or parameters of each measurement. Frequency/Channel setting, Amplitude
setting (Preamp, Attenuation, External offset), Reference setting information Frequency/Trigger)
③Measurement Setting Information
-Spectrum Analyzer Operation Mode Information: Displays the operation mode of
spectrum analyzer, Sweep or FFT
-Detector Type Setting Information: Displays the current selected detector types, Normal,
Peak, RMS, Negative Peak, and Sample
-Spectrum Window’s X Scale Setting Information: Displays RBW, VBW settings
[A]: Auto mode, [M]: Manual mode
-Sweep Time Information: Displays current sweep time
-Average Number Information set through BW/AVG hard key. It shows the number of
traces to be averaged.

GSM/GPRS/EDGE SIGNAL ANALYZER 6
JD7105B Base Station Analyzer
④Trace Information
C: Captured
M: Max Hold
m: Min Hold
W: Write Current Trace (Indicates current active trace)
L: Loaded
F: Trace View Off
⑤Information on Marker Table displays up to 6 markers
⑥Screen Menu Title
⑦Screen Menu and Sub-menu
⑧Scale Unit Information: dBm, dBmV, dBuV, V, and W
⑨User Input Window: Activates when user input menu or key is selected. Pressing PREV hard
key will cancel or deactivate user input window. Inactivate user input window before using 7-hot
keys.
NOTE: It is very important to inactivate the user input window when you intend to use the hot
key menu on the numeric keys.
⑩Pass/Fail Indicator

7 GSM/GPRS/EDGE SIGNAL ANALYZER
JD7105B Base Station Analyzer
CONNECTING A CABLE
Direct Connection
PA Output Port and RF In Port Connection
Indirect Connection
Monitor Port and RF In Port Connection
!
The maximum power for the Spectrum Analyzer RF In 50Ωport is 30 dBm (1
Watt). If the input signal level to be measured is greater than 30 dBm, use a High
Power Attenuator to prevent damage when you directly connect the signal to the
instrument. Or connect a signal from the coupling port of a directional coupler.

GSM/GPRS/EDGE SIGNAL ANALYZER 8
JD7105B Base Station Analyzer
Over The Air (OTA)
OTA Connection
!
The maximum power for the Spectrum Analyzer RF In 50Ωport is 30 dBm (1
Watt). If the input signal level to be measured is greater than 30 dBm, use a High
Power Attenuator to prevent damage when you directly connect the signal to the
instrument. Or connect a signal from the coupling port of a directional coupler.

9 GSM/GPRS/EDGE SIGNAL ANALYZER
JD7105B Base Station Analyzer
SPECTRUM ANALYSIS MEASUREMENT
Setting Mode
Step Description
1. Connect the cable
Connect the signal to the Spectrum Analyzer RF In 50Ω
port using the cable whose loss was measured.
2. Select the mode
MODE
[Signal Analyzer]
[GSM]
[Spectrum]
Press the MODE hard key.
Press the Signal Analyzer soft key.
Press the GSM soft key.
Press the Spectrum soft key. (Spectrum mode is set by
default.)
Setting Frequency
Step Description
1. Set the frequency
FREQ/DIST
[Center Frequency]
Enter a value
[GHz], [MHz], [kHz], or [Hz]
or
[Channel Number]
Enter a value
[Forward]or [Reverse]
Press the FREQ/DIST hard key.
Press the Center Frequency soft key.
Use the numeric keys, the rotary knob, or the arrow keys.
When using the numeric keys, the input is completed by
selecting one of the unit soft keys.
Press the Channel Number soft key.
Enter a channel number using the numeric keys.
Select the direction by pressing the Forward or Reverse.
2. Select the channel standard
[Channel Standard]
Select a channel standard
[Select] or ENTER
Press the Channel Standard soft key to get the pop-up
window of the channel standard list.
Press the arrow keys, rotate the knob, or press the Page Up
and Page Down soft keys to highlight a frequency band to
select.
Press the Select soft key or the ENTER hard key.

GSM/GPRS/EDGE SIGNAL ANALYZER 10
JD7105B Base Station Analyzer
FREQ/DIST
CENTER FREQUENCY:Changes the center frequency setup. Values can be entered with the
numeric keys, the rotary knob, or the arrow keys. When using the numeric keys, the input is
completed by selecting one of the unit soft keys including GHz, MHz, kHz, and Hz. When using
the rotary knob or the arrow keys, the frequency changes in a predefined frequency step. The
frequency step can be configured by selecting the Frequency Step soft key.
CHANNEL NUMBER: Enters a channel number and selects the Forward or Reverse soft key.
When using the rotary knob or the arrow keys, the channel changes in a predefined channel step.
The channel step can be configured by selecting the Channel Step soft key.
FREQUENCY STEP: Defines the moving step size of the Center Frequency when using the
rotary knob or the arrow keys. The step size can be entered by using numeric keys and the unit
soft keys.
CHANNEL STEP: Defines the moving step size of the Channel Number when using the rotary
knob or the arrow keys. The step size can be entered by using numeric keys and the Enter soft
key.
CHANNEL STANDARD: When the channel standard is selected from the list, the center
frequency information on the display screen will be mapped accordingly to the selected channel
standard. The channel standards available in the instrument are listed in the Appendix C – Band,
Frequency & Channel Standard.
Setting Amplitude
Step Description
1. Set the reference level
AMP/SCALE
[Reference Level]
Enter a reference level value
[dBm] or ENTER
Press the AMP/SCALE hard key.
Press the Reference Level soft key.
Use the numeric keys or the rotary knob that changes in a 10
dB step.
Press the dBm soft key or the ENTER hard key.
2. Set the attenuation level
[Attenuation]
<Auto> or <Manual>
Enter an attenuation value
Press the Attenuation soft key. The Auto mode is set by
default. This key toggles between the Auto and Manual.
Press the Attenuation soft key to highlight the Manual mode
and change the attenuation value to optimize S/N.
Use the numeric keys or the rotary knob that changes in a 5
dB step. The attenuation setting range is 0 to 55 dB.

11 GSM/GPRS/EDGE SIGNAL ANALYZER
JD7105B Base Station Analyzer
AMP/SCALE
AUTO SCALE: The instrument can automatically set the scale to the minimum and maximum
values on the Y-axis of the graph for optimum display of the traces measured. Each time the Auto
Scale is selected, the top and bottom scales are set to the minimum and maximum values with
margin on the Y-axis of the display screen.
REFERENCE LEVEL: Sets the maximum Y-axis range when using the Spectrum Analyzer or
Signal Analyzer function.
SCALE/DIV: Is used only for the Spectrum measurement screen. It represents the value of one
division on the horizontal scale. The default value is 10 dB per division and the Y-Scale is set to
100 dB. Selecting the Scale/Div soft key enables to set the value to 1 dB per division with the
numeric keys or the rotary knob.
ATTENUATION
AUTO: Input attenuator’s value is automatically set depending on the reference level. This is
the default operation mode, so it is recommended to use this mode unless a special
measurement condition is needed.
MANUAL: Sets the attenuator’s value for the Spectrum Analyzer RF In 50Ωport. The
reference level changes according to the change of the attenuator’s value, but the
attenuator’s value does not change when the reference level is changed.
!
If the input signal level is higher than +30 dBm or higher than the allowable mixer
input limit per input attenuator’s value set by the user, a “IF Overload” message will
be displayed on the screen indicating that the input attenuation value must be
increased. When the instrument is exposed to an over power condition for a long
time, its performance may be degraded.
PREAMP: Turns on or off the internal pre-amplifier. The pre-amplifier is to amplify a low-level
input signal. This soft key toggles between the On and Off. When it is turned on, the allowable
attenuation input range is 0 dB to 10 dB with 5 dB step. If user sets attenuation value beyond 10
dB, then the instrument will automatically turn off pre-amplifier to display low level signal properly
on the screen.
UNITS: Sets the scale unit on the display among dBm, dBmV, dBuV, V, and W.
EXTERNAL OFFSET: Sets an external offset value. An offset consists of a cable loss and a user
offset and the measurement result shows the value reflecting both offset values. When the
external offset value is set at 40 dB in the Spectrum mode, the measurement result compensates
40 dB at both the Spectrum Analyzer and Signal Analyzer modes.

GSM/GPRS/EDGE SIGNAL ANALYZER 12
JD7105B Base Station Analyzer
Setting Averaging
BW/AVG
AVERAGE: Sets the number of measurements to be averaged for the trace presentation. A
maximum of 99 times of averaging can be set.
Setting Sweep Mode
SWEEP
This hot key is used to set the sweep parameters. The user input window must be inactive first to get
the Sweep hot key function other than the number input.
SWEEP MODE:Sets the sweep method. Toggle between Continue and Single.
Step Description
1. Set the sweep mode
SWEEP
[Sweep Mode]
Press the SWEEP hot key. It is the number 1 key in the
numeric keypad.
Press the Sweep Mode soft key. Toggle between
Continue and Single.
Setting Trace and Display
TRACE/DISPLAY
SELECT TRACE: Selects an active trace from T1 to T6. Trace numbers are assigned to each
captured trace or loaded trace. Pressing one of the 6 trace number soft keys sets the selected
trace number as the active trace on the display screen.
Step Description
1. Set the averaging
BW/AVG
[Average]
Press the BW/AVG hard key.
Press the Average soft key.
2.
Enter number of averaging to set Use the numeric keys and input a number between 1 and 99.
When the averaging reaches to the number set here, a new
measurement value replaces the earliest measurement value
in sequence.
3. [Enter] or ENTER
Press the Enter soft key or the ENTER hard key.

13 GSM/GPRS/EDGE SIGNAL ANALYZER
JD7105B Base Station Analyzer
CLEAR WRITE: Clears the selected trace and writes or assigns the current trace.
MAX HOLD: Sets the active trace to display the maximum response of the input signal. Active
trace compares newly acquired data with the trace shown on the screen and displays the bigger
trace on the display screen.
MIN HOLD: Sets the active trace to display the minimum response of the input signal. Active trace
compares newly acquired data with the trace shown on the screen and displays the smaller trace
on the display screen.
CAPTURE: Captures a current trace on the display screen with the selected trace number.
TRACE VIEW: Displays the trace of the selected trace number on the display screen or hides it
from the display screen. Press the Select Trace soft key to select a trace number and then press
the Trace View soft key to toggle between the Off to hide and On to restore a hidden trace.
TRACE CLEAR ALL: Deletes all traces from the instrument and initializes the trace settings.
Measurement Example
GSM Spectrum Analysis Measurement Screen
Using Marker
MARKER
Marker is used to get the information about a specific trace. Six markers can be set on the display and
each marker can be used independently. The X and Y coordinates of the trace are displayed when the

GSM/GPRS/EDGE SIGNAL ANALYZER 14
JD7105B Base Station Analyzer
marker is placed on any position of the trace. The position displaying the marker’s X and Y
coordinates may be slightly different for each measurement mode and refer to the description of each
measurement. There are three different marker types available: Normal, Delta, and Delta pair. Marker
position can be set manually by entering numeric values (frequency) when one of the marker types is
selected.
SELECT MARKER:Selects an active marker whose position can be changed with the rotary
knob or the arrow keys. The assigned number of the active marker is displayed in the Select
Marker menu box and the active marker number is also displayed right next to the active marker
on the trace when the Marker View is set to On.
MARKER VIEW:Displays the selected marker on the screen or hides it. When the Marker View
is turned off and then on again in the same measurement mode, markers appear at the previous
positions. If a measurement mode is changed, markers are not restored to their previous positions.
NORMAL:This Normal marker type provides the reading of a marker position on the trace along
with the marker number between 1 and 6.
DELTA:This Delta marker type is associated with a Normal marker. A Normal marker must be set
before a Delta marker is set. When the Delta marker is set, the position set by the Delta marker
becomes the reference position of the Normal marker and the marker’s X and Y values displays
the difference compared with the Delta marker.
DELTA PAIR: This Delta Pair marker type is associated with a Normal marker. A Normal marker
must be set before a Delta Pair marker is set. When the Delta Pair marker is set, the position set
by the Delta Pair marker becomes the reference position of the Normal marker and the marker’s X
and Y values displays the difference compared with the Delta Pair marker. The reference position
will be varied in accordance with trace change.
MARKER ALL OFF: Turns all the markers the screen off. When the Marker View is selected for
those markers, the instrument displays those markers back at the previous position. If a
measurement mode is changed, current settings are not restored.
MARKER: Sets the X coordinate of the active marker as selected.
MARKERCENTER:Sets the frequency of the active marker to the center frequency of
spectrum analyzer.
MARKERSTART:Sets the frequency of the active marker to the start frequency of
spectrum analyzer.
MARKERSTOP:Sets the frequency of the active marker to the stop frequency of spectrum
analyzer.

15 GSM/GPRS/EDGE SIGNAL ANALYZER
JD7105B Base Station Analyzer
Using Peak Search
PEAK SEARCH
Each time the Peak Search soft key is pressed, the active marker is positioned at the highest peak of
the trace.
PEAK SEARCH:Moves the active marker to the highest peak of the trace.
NEXT PEAK:Moves the active marker to the second highest peak of the trace.
NEXT PEAK RIGHT:Moves the active marker to the highest peak to the right of its current
position.
NEXT PEAK LEFT:Moves the active marker to the highest peak to the left of its current position.
MIN SEARCH:Moves the active marker to the lowest peak of the trace.
ALWAYS PEAK:When the Always Peak is set to On, the instrument moves the active marker
automatically to the highest peak of the trace every time the trace is refreshed.

GSM/GPRS/EDGE SIGNAL ANALYZER 16
JD7105B Base Station Analyzer
RF ANALYSIS MEASUREMENTS
GSM/GPRS/EDGE Signal Analysis provides the following measurements for RF Analysis.
Channel Power
Occupied Bandwidth
Spectrum Emission Mask
Spurious Emissions
Setting Mode
Step Description
1. Connect the cable
Connect the signal to the Spectrum Analyzer RF In 50Ω
port using the cable whose loss was measured.
2. Select the mode
MODE
[Signal Analyzer]
[GSM]
[RF Analysis]
Press the MODE hard key.
Press the Signal Analyzer soft key.
Press the GSM soft key.
Press the RF Analysis soft key.
Setting Frequency
Step Description
1. Set the frequency
FREQ/DIST
[Center Frequency]
Enter a value
[GHz], [MHz], [kHz], or [Hz]
or
[Channel Number]
Enter a value
[Forward]or [Reverse]
Press the FREQ/DIST hard key.
Press the Center Frequency soft key.
Use the numeric keys, the rotary knob, or the arrow keys.
When using the numeric keys, the input is completed by
selecting one of the unit soft keys.
Press the Channel Number soft key.
Enter a channel number using the numeric keys.
Select the direction by pressing the Forward or Reverse.
2. Select the channel standard
[Channel Standard]
Select a channel standard
[Select] or ENTER
Press the Channel Standard soft key to get the pop-up
window of the channel standard list.
Press the arrow keys, rotate the knob, or press the Page Up
and Page Down soft keys to highlight a frequency band to
select.
Press the Select soft key or the ENTER hard key.

17 GSM/GPRS/EDGE SIGNAL ANALYZER
JD7105B Base Station Analyzer
FREQ/DIST
This setting is not used in the Spurious Emissions mode.
CENTER FREQUENCY:Changes the center frequency setup. Values can be entered with the
numeric keys, the rotary knob, or the arrow keys. When using the numeric keys, the input is
completed by selecting one of the unit soft keys including GHz, MHz, kHz, and Hz. When using
the rotary knob or the arrow keys, the frequency changes in a predefined frequency step. The
frequency step can be configured by selecting the Frequency Step soft key.
CHANNEL NUMBER: Enters a channel number and selects the Forward or Reverse soft key.
When using the rotary knob or the arrow keys, the channel changes in a predefined channel step.
The channel step can be configured by selecting the Channel Step soft key.
FREQUENCY STEP: Defines the moving step size of the Center Frequency when using the
rotary knob or the arrow keys. The step size can be entered by using numeric keys and the unit
soft keys.
CHANNEL STEP: Defines the moving step size of the Channel Number when using the rotary
knob or the arrow keys. The step size can be entered by using numeric keys and the Enter soft
key.
CHANNEL STANDARD: When the channel standard is selected from the list, the center
frequency information on the display screen will be mapped accordingly to the selected channel
standard. The channel standards available in the instrument are listed in the table in the Appendix
C – Band, Frequency & Channel Standard.
Setting Amplitude
Step Description
1. Set the reference level
AMP/SCALE
[Reference Level]
Enter a reference level value
[dBm] or ENTER
Press the AMP/SCALE hard key.
Press the Reference Level soft key.
Use the numeric keys or the rotary knob that changes in a 10
dB step.
Press the dBm soft key or the ENTER hard key.
2. Set the attenuation level
[Attenuation]
<Auto> or <Manual>
Enter an attenuation value
Press the Attenuation soft key. The Auto mode is set by
default. This key toggles between the Auto and Manual.
Press the Attenuation soft key to highlight the Manual mode
and change the attenuation value to optimize S/N.
Use the numeric keys or the rotary knob that changes in a 5
dB step. The attenuation setting range is 0 to 55 dB.

GSM/GPRS/EDGE SIGNAL ANALYZER 18
JD7105B Base Station Analyzer
AMP/SCALE
AUTO SCALE: The instrument can automatically set the scale to the minimum and maximum
values on the Y-axis of the graph for optimum display of the traces measured. Each time the Auto
Scale is selected, the top and bottom scales are set to the minimum and maximum values with
margin on the Y-axis of the display screen.
REFERENCE LEVEL: Sets the maximum Y-axis range when using the Spectrum Analyzer or
Signal Analyzer function.
SCALE/DIV: Is used only for the Spectrum measurement screen. It represents the value of one
division on the horizontal scale. The default value is 10 dB per division and the Y-Scale is set to
100 dB. Selecting the Scale/Div soft key enables to set the value to 1 dB per division with the
numeric keys or the rotary knob.
ATTENUATION
AUTO: Input attenuator’s value is automatically set depending on the reference level. This is
the default operation mode, so it is recommended to use this mode unless a special
measurement condition is needed.
MANUAL: Sets the attenuator’s value for the Spectrum Analyzer RF In 50Ωport. The
reference level changes according to the change of the attenuator’s value, but the
attenuator’s value does not change when the reference level is changed.
!
If the input signal level is higher than +30 dBm or higher than the allowable mixer
input limit per input attenuator’s value set by the user, a “IF Overload” message will
be displayed on the screen indicating that the input attenuation value must be
increased. When the instrument is exposed to an over power condition for a long
time, its performance may be degraded.
PREAMP: Turns on or off the internal pre-amplifier. The pre-amplifier is to amplify a low-level
input signal. This soft key toggles between the On and Off. When it is turned on, the allowable
attenuation input range is 0 dB to 10 dB with 5 dB step. If user sets attenuation value beyond 10
dB, then the instrument will automatically turn off pre-amplifier to display low level signal properly
on the screen.
UNITS: Sets the scale unit on the display among dBm, dBmV, dBuV, V, and W.
EXTERNAL OFFSET: Sets an external offset value. An offset consists of a cable loss and a user
offset and the measurement result shows the value reflecting both offset values. When the
external offset value is set at 40 dB in the Spectrum mode, the measurement result compensates
40 dB at both the Spectrum Analyzer and Signal Analyzer modes.

19 GSM/GPRS/EDGE SIGNAL ANALYZER
JD7105B Base Station Analyzer
Setting Averaging
BW/AVG
AVERAGE: Sets the number of measurements to be averaged for the trace presentation. A
maximum of 99 times of averaging can be set.
Setting Sweep Mode
SWEEP
This hot key is used to set the sweep parameters. The user input window must be inactive first to get
the Sweep hot key function other than the number input.
SWEEP MODE:Sets the sweep method. Toggle between Continue and Single.
Step Description
1. Set the sweep mode
SWEEP
[Sweep Mode]
Press the SWEEP hot key. It is the number 1 key in the
numeric keypad.
Press the Sweep Mode soft key. Toggle between
Continue and Single.
Setting Trigger Source
TRIGGER
This hot key is used to select the trigger source among RF Burst, Internal FB, RF Burst & TS,
External, and Free. It is the same number 4 key in the numeric keypad functioning when the value
input bar on the screen is inactive.
Step Description
1. Set the averaging
BW/AVG
[Average]
Press the BW/AVG hard key.
Press the Average soft key.
2.
Enter number of averaging to set Use the numeric keys and input a number between 1 and 99.
When the averaging reaches to the number set here, a new
measurement value replaces the earliest measurement value
in sequence.
3. [Enter] or ENTER
Press the Enter soft key or the ENTER hard key.

GSM/GPRS/EDGE SIGNAL ANALYZER 20
JD7105B Base Station Analyzer
RF BURST:Sets the trigger level when using the RF Burst (wideband) trigger. The value is
relative to the peak of the signal. RF Burst is also known as RF Envelope.
INTERNAL FB (FREE BURST): Sets the trigger level to FB if there is a frequency burst signal.
RF BURST & TS (TRAINING SEQUENCE): Sets the trigger level to Training Sequence Code.
EXTERNAL:Sets the trigger level to external trigger reference.
FREE:Sets the free trigger (auto trigger).