LTE FDD

Carrier Settings ARB

This topic describes carrier settings for Waveform Playback (ARB) capability. Settings are unique for each selected component carrier.

The SCPI mnemonic CCARrier<n> denotes CCARrier[1]|2|…|<n> where <n> is the number of configured carriers.

General

Enabled

This setting specifies the enable state of a carrier.

SCPI Command	[:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>[:STATe] OFF\|ON\|0\|1 [:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>[:STATe]?
SCPI Example	:RAD:LTEF:WAV:CCAR OFF :RAD:LTEF:WAV:CCAR?
State Saved	Yes
Preset	ON
Initial S/W Revision	A.14.00

Waveform Generation Length

Set the waveform generation length.

SCPI Command	[:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>:LENGth <time> [:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>:LENGth?
SCPI Example	:RAD:LTEF:WAV:CCAR:LENG 20 :RAD:LTEF:WAV:CCAR:LENG?
State Saved	Yes
Preset	10 ms
Min	10 ms
Max	30720 ms [Uplink E-UTRA/Uplink eMTC] 10240 ms [PRACH E-UTRA]
Resolution	1 ms [Uplink E-UTRA/Uplink eMTC] 10 ms [PRACH E-UTRA]
Initial S/W Revision	A.14.00

Carrier Type

This setting returns the carrier type. This setting is automatically set when a carrier is added.

SCPI Command	[:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>:TYPE?
SCPI Example	:RAD:LTEF:WAV:CCAR:TYPE?
Notes	SCPI only, Query only Returns FDDULEUTRA\|FDDPRACHEUTRA\|CW
State Saved	No
Preset	FDDULEUTRA
Range	Uplink E-UTRA \| PRACH E-UTRA \| Continuous Wave
Initial S/W Revision	A.14.00

Baseband

The parameters in the Baseband group set the baseband settings of a carrier.

Auto Oversampling Ratio

This parameter sets the mode of oversampling rate control.

SCPI Command	[:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>:OSRatio:AUTO[:STATe] OFF\|ON\|0\|1 [:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>:OSRatio:AUTO[:STATe]?
SCPI Example	:RAD:LTEF:WAV:CCAR:OSR:AUTO ON :RAD:LTEF:WAV:CCAR:OSR:AUTO?
State Saved	Yes
Preset	ON
Initial S/W Revision	A.14.00

Oversampling Ratio

[Uplink E-UTRA/eMTC]

Sets the oversampling ratio.

If you select AUTO, the signal generator automatically sets an optimized oversampling ratio for the current setup.

The Total Sample Points value is automatically determined based on the oversampling ratio. Using a larger oversampling ratio result in a more completely filtered image, but also uses more waveform memory by increasing the number of waveform points. In the case where the System Bandwidth = 1.4MHz, Auto = 2, else Auto = 1.

This parameter sets oversampling ratio of waveform generation. This value is used when Auto Oversampling Ratio is Off.

SCPI Command	[:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>:OSRatio <integer> [:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>:OSRatio?
SCPI Example	:RAD:LTEF:WAV:CCAR:OSR 2 :RAD:LTEF:WAV:CCAR:OSR?
Dependencies	This value is used when Oversampling Rate Mode is Off
State Saved	Yes
Preset	2
Min	1
Max	7
Initial S/W Revision	A.14.00

Base Sampling Rate

[Uplink E-UTRA/eMTC][PRACH]

Base Sampling Rate is a sampling rate without Oversampling Ratio (OSR).

There is a relation among Base Sampling Rate, OSR, Total Sample Points and Waveform Generation Length as follows.

Total Sample Points = Base Sampling Rate (MHz) x OSR x 1000 x Waveform Generation Length (ms)

Ex) System BW = 5MHz, OSR = 1 (Auto), Waveform Generation Length = 10 (ms) case:

Total Sample Points = 7.68 (MHz) x 1 x 1000 x 10 (ms) = 76800 (Points)

The software sets the Base Sampling Rate based on the System Bandwidth (BW) as follows:

System BW = 1.4 MHz, Base Sampling Rate = 1.92 MHz.

System BW = 3 MHz, Base Sampling Rate = 3.84 MHz.

System BW = 5 MHz, Base Sampling Rate = 7.68 MHz.

System BW = 10 MHz, Base Sampling Rate = 15.36 MHz.

System BW = 15 MHz, Base Sampling Rate = 23.04 MHz.

System BW = 20 MHz, Base Sampling Rate = 30.72 MHz.

[Uplink E-UTRA/eMTC]

When Carrier Aggregation has multiple E-UTRA carriers or E-UTRA carrier of 15 MHz System Bandwidth and NB-IoT carrier(s), the Base Sampling Rate = 30.72 MHz.

[PRACH]

For multi-carrier waveforms, the Base Sampling Rate = 30.72 MHz.

SCPI Command	[:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>:SRATe:BASE?
SCPI Example	:RAD:LTEF:WAV:CCAR:SRAT:BASE?
Notes	Query only
State Saved	No
Preset	15.36 MHz
Range	Value SCPI 1.92 MHz F1M92 3.84 MHz F3M84 7.68 MHz F7M68 15.36 MHz F15M36 23.04 MHz F23M04 30.72 MHz F30M72
Initial S/W Revision	A.14.00

Total Sample Points

View the waveform length, displayed in points. You cannot edit this cell.

Total Sample Points is directly related to the Oversampling Ratio value selected. Increasing the oversampling ratio increases the total sample points.

SCPI Command	[:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>:SAMPles:COUNt?
SCPI Example	:RAD:LTEF:WAV:CCAR:SAMP:COUN?
Notes	Query only
State Saved	No
Preset	153600
Initial S/W Revision	A.14.00

Frequency Offset

[Uplink E-UTRA/eMTC]

Sets the frequency offset for the carrier relative to the signal generator’s frequency setting.

The range of the parameter is coupled to the Oversampling Ratio, the Base Sampling Rate, the System Bandwidth and the max ARB Sample Clock of the connected signal generator.

Frequency Offset and Cell ID are always editable, even if Auto Carrier Aggregation Configuration is on.

In either case below (1 or 2), auto configuration is performed for Frequency Offset and Cell ID.

When any of these actions are performed: Add Carrier, Delete Carrier or Change System BW, and the Auto Carrier Aggregation Configuration parameter is on.
When the Auto Carrier Aggregation Configuration parameter is changed from off to on.

Auto configuration sets Cell ID same as Component Carrier Index.

If Auto Carrier Aggregation Configuration is set to off, auto configuration does not work.

[PRACH]

Sets the frequency offset for the carrier relative to the signal generator’s frequency setting.

The range of the parameter is coupled to Oversampling Ratio, Base Sampling Rate, System Bandwidth and the max ARB Sample Clock of the connected signal generator.

Frequency Offset and Cell ID are always editable, even if Auto Carrier Aggregation Configuration is on.

In either case below (1 or 2), auto configuration is performed for Frequency Offset.

When any of these actions are performed: Add Carrier, Delete Carrier or Change System BW, and the Auto Carrier Aggregation Configuration parameter is on.
When the Auto Carrier Aggregation Configuration parameter is changed from off to on.

If Auto Carrier Aggregation Configuration is set to off, auto configuration does not work.

SCPI Command	[:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>:FREQuency:OFFSet <freq> [:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>:FREQuency:OFFSet?
SCPI Example	:RAD:LTEF:WAV:CCAR:FREQ:OFFS 1000000 :RAD:LTEF:WAV:CCAR:FREQ:OFFS?
State Saved	Yes
Preset	0 Hz
Initial S/W Revision	A.14.00

Power

Sets the power level in dB for the selected carrier in a multiple carrier configuration, relative to the power settings defined for the other carriers in the configuration.

You can ignore this parameter for single carrier configurations.

In single carrier configurations, the amplitude of the signal is determined by the Amplitude setting in the Instrument node.

SCPI Command	[:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>:POWer <rel_ampl> [:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>:POWer?
SCPI Example	:RAD:LTEF:WAV:CCAR:POW -30dB :RAD:LTEF:WAV:CCAR:POW?
State Saved	Yes
Notes	Unit in GUI: dB
Preset	0 dB
Min	-60 dB
Max	0 dB
Resolution	0.001 dB
Initial S/W Revision	A.14.00

Timing Offset

Specifies the length of timing offset.

The maximum value of the range depends on Waveform Generation Length.

If Timing Offset cannot be divided by sampling period (1 / Base Sampling Rate / Oversampling Ratio), it is rounded to the nearest sample point.

SCPI Command	[:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>:TIMing:OFFSet <time> [:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>:TIMing:OFFSet?
SCPI Example	:RAD:LTEF:WAV:CCAR:TIM:OFFS 0.1ns :RAD:LTEF:WAV:CCAR:TIM:OFFS?
Notes	Not used for CW Carrier Unit in GUI: s
State Saved	Yes
Preset	0.000 us
Min	0.000 us
Max	Minimum (Waveform Generation Length – 1 ns or 10 ms – 1 ns) (us)
Initial S/W Revision	A.14.00

Initial Phase

Sets the initial phase of the carrier.

SCPI Command	[:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>:INITial:PHASe <integer> [:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>:INITial:PHASe?
SCPI Example	:RAD:LTEF:WAV:CCAR:INIT:PHAS 300 :RAD:LTEF:WAV:CCAR:INIT:PHAS?
Notes	Not used for CW Carrier Unit in GUI: deg
State Saved	Yes
Preset	0
Min	0
Max	359
Initial S/W Revision	A.14.00

Spectrum Control

This section describes the settings of Spectrum Control.

Pre-Filter Clipping

Set the clipping (limit) level of the I/Q waveform before filtering.

SCPI Command	[:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>:CLIPping:PRE <real> [:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>:CLIPping:PRE?
SCPI Example	:RAD:LTEF:WAV:CCAR:CLIP:PRE 20 :RAD:LTEF:WAV:CCAR:CLIP:PRE?
Notes	Value is in percent [%], 100 means 100 % 100 % means "no clipping" Unit in GUI: %
State Saved	Yes
Preset	100
Min	10
Max	100
Resolution	0.1
Initial S/W Revision	A.14.00

Post-Filter Clipping

Set the clipping (limit) level of the I/Q waveform after filtering.

SCPI Command	[:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>:CLIPping:POST <real> [:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>:CLIPping:POST?
SCPI Example	:RAD:LTEF:WAV:CCAR:CLIP:POST 30 :RAD:LTEF:WAV:CCAR:CLIP:POST?
Notes	Value is in percent [%], 100 means 100 % 100 % means "no clipping" Unit in GUI: %
State Saved	Yes
Preset	100
Min	10
Max	100
Resolution	0.1
Initial S/W Revision	A.14.00

Auto Symbol Rolloff Length Configuration

Double-click or use the drop-down menu to turn the auto symbol rolloff length configuration on or off.

SCPI Command	[:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>:SROLloff:AUTO[:STATe] OFF\|ON\|0\|1 [:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>:SROLloff:AUTO[:STATe]?
SCPI Example	:RAD:LTEF:WAV:CCAR:SROL:AUTO 1 :RAD:LTEF:WAV:CCAR:SROL:AUTO?
State Saved	Yes
Preset	ON [E-UTRA/eMTC]
Initial S/W Revision	A.14.00

Symbol Rolloff Length

The cyclic prefix used with SC-FDMA modulation in LTE results in a discontinuity between SC-FDMA symbols. Windowing is used in the Signal Studio for 3GPP LTE software to reduce spurious signal generation between symbols caused by this discontinuity. Symbol Rolloff sets the windowing length in Basic Time Units. Adjusting the Symbol Rolloff Length can improve ACPR performance, however this may result in degraded EVM performance.

Basic Time Unit (Ts) = 1/(15000 x 2048) seconds

SCPI Command	[:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>:SROLloff:LENGth <integer> [:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>:SROLloff:LENGth?
SCPI Example	:RAD:LTEF:WAV:CCAR:SROL:LENG 20 :RAD:LTEF:WAV:CCAR:SROL:LENG?
State Saved	Yes
Notes	Unit in GUI: Ts
Preset	15 Ts [E-UTRA/eMTC]
Min	0
Max	400
Initial S/W Revision	A.14.00

Baseband Filter

Sets the state of the baseband filter on or off. In most testing conditions, Keysight recommends using the baseband filter (Baseband Filter = On) to achieve a balance between ACPR and EVM performance.

SCPI Command	[:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>:BFILter[:STATe] OFF\|ON\|0\|1 [:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>:BFILter[:STATe]?
SCPI Example	:RAD:LTEF:WAV:CCAR:BFIL ON :RAD:LTEF:WAV:CCAR:BFIL?
State Saved	Yes
Preset	ON
Initial S/W Revision	A.14.00

Carrier Aggregation

The Carrier Aggregation node holds the settings of carrier aggregation.

Auto Carrier Aggregation Configuration

Sets the state of Auto Carrier Aggregation Configuration on or off.

Frequency Offset and Cell ID are always editable, even if Auto Carrier Aggregation Configuration is on.

In either case below (1 or 2), auto configuration is performed for Frequency Offset and Cell ID.

When any of these actions are performed: Add Carrier, Delete Carrier or Change System BW, and the Auto Carrier Aggregation Configuration parameter is on.
When the Auto Carrier Aggregation Configuration parameter is changed from off to on.

Auto configuration sets Cell ID same as Component Carrier Index.

If Auto Carrier Aggregation Configuration is set to off, auto configuration does not work.

Frequency Offset of NB-IoT carrier is not automatically set by this parameter.

SCPI Command	[:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>:CAConfig:AUTO[:STATe] OFF\|ON\|0\|1 [:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>:CAConfig:AUTO[:STATe]?
SCPI Example	:RAD:LTEF:WAV:CCAR:CAC:AUTO OFF :RAD:LTEF:WAV:CCAR:CAC:AUTO?
Dependencies	This setting affects all carriers in the same carrier aggregation group Changing the state of one carrier to on also changes the state of other carriers in the same carrier aggregation group so that all carriers have the same value.
State Saved	Yes
Preset	ON
Initial S/W Revision	A.14.00

Primary Cell

Sets the primary cell (PCell) in active component carriers.

The primary cell is only one in the component carriers.

Component carriers are composed of the primary cell and all secondary cells.

If the component carrier for the primary cell is deleted or its state is changed, a suitable component carrier for the primary cell is automatically set by the software.

See 3GPP TS 36.331 for more information.

SCPI Command	[:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>:PCELl[:STATe] OFF\|ON\|0\|1 [:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<carrier>:PCELl[:STATe]?
SCPI Example	:RAD:LTEF:WAV:CCAR:PCEL ON :RAD:LTEF:WAV:CCAR:PCEL?
Dependencies	Only one carrier in a carrier aggregation group can be a primary cell At least one carrier must be turned on Turning on this setting on one carrier turns off the setting of other carriers in the same carrier aggregation group
State Saved	Yes
Preset	On (at the first carrier in a carrier aggregation group), otherwise Off
Initial S/W Revision	A.14.00

Carrier Settings ARB

General

Baseband

Spectrum Control

Carrier Aggregation

Uplink

PRACH

Carrier Configuration Tools

General

Enabled

Waveform Generation Length

Carrier Type

Baseband

Auto Oversampling Ratio

Oversampling Ratio

Base Sampling Rate

Total Sample Points

Frequency Offset

Power

Timing Offset

Initial Phase

Spectrum Control

Pre-Filter Clipping

Post-Filter Clipping

Auto Symbol Rolloff Length Configuration

Symbol Rolloff Length

Baseband Filter

Carrier Aggregation

Auto Carrier Aggregation Configuration

Primary Cell