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 Even Frame Alignment

[Uplink NB-IoT]

Double-click or use the drop-down menu to turn Waveform Generation Length Even Frame Alignment on or off.

On: The waveform generation length is automatically set to multiple of 20 ms by adding the tail gap period.
Off: You can set the waveform generation length.

SCPI Command	[SOURce]:RADio:LTEFdd:WAVeform:RTIMe:CCARrier:LENGth:EVEN ON\|OFF\|1\|0 [SOURce]:RADio:LTEFdd:WAVeform:RTIMe:CCARrier:LENGth:EVEN?
SCPI Example
State Saved	Yes
Preset	ON

Waveform Generation Length

[Uplink E-UTRA/Uplink eMTC/PRACH E-UTRA/Prach NB-IoT/Uplink NB-IoT/Downlink NB-IoT]

Set the waveform generation length.

Waveform Generation Length must be a multiple of NPRACH Resource Periodicity on the Channel Setup node and the input value is rounded up to the nearest multiple of NPRACH Resource Periodicity.

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 20 ms [for Uplink NB-IoT/ Downlink NB-IoT] When NB-IoT-NPRACH is selected then initially it is set to 80 ms. The Preset value, however, is 10 ms.
Min	10 ms
Max	30720 ms [Uplink E-UTRA/Uplink eMTC] 10240 ms [PRACH E-UTRA] 47360 ms [Uplink NB-IoT] 40960 ms [NB-IoT NPRACH / Downlink NB-IoT]
Resolution	1 ms [Uplink E-UTRA/Uplink eMTC] 10 ms [PRACH E-UTRA] 1 ms [Uplink NB-IoT] 10 ms [Downlink NB-IoT]
Initial S/W Revision	A.14.00
Modified S/W Revision	A.19.00

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\| FDDPRACHNIOT\|FDDULNIOT
State Saved	No
Preset	FDDULEUTRA
Range	Uplink E-UTRA \| PRACH E-UTRA \| Continuous Wave\| Uplink NB-IOT \| Prach NB-IOT
Initial S/W Revision	A.14.00
Modified S/W Revision	A.19.00

Baseband

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

Auto Oversampling Ratio

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/Uplink NB-IoT/Prach-NB-IoT]

Sets the oversampling ratio of waveform generation.

This setting is available and used when Auto Oversampling Ratio is set to Off.

If Auto Oversampling Ratio is set to On, the signal generator automatically sets an optimized oversampling ratio for the current setup.

Double-click to set the oversampling ratio.

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 Uplink E-UTRA/eMTC: In the case where the System Bandwidth = 1.4 MHz, Auto = 2, else Auto = 1.

In Uplink NB-IoT, Prach NB-IoT: System Bandwidth is 200 kHz Choices: AUTO | 1 | 2 | 3 | 4 | 5 | 6 | 7 Default: AUTO

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 Auto Oversampling Ratio is Off.
State Saved	Yes
Preset	2 When Auto Oversampling Ratio is OFF, then Oversampling Ratio is 1.
Min	1
Max	7
Initial S/W Revision	A.14.00
Modified S/W Revision	A.19.00

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)

Example: 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.

[Uplink NB-IoT]

Displays Base Sampling Rate for each System BW or multi-carrier condition.

When System BW is 200 kHz, Base Sampling Rate is 1.92 MHz.

Example: System BW = 200 kHz, OSR = 1 (Auto), Waveform Generation Length = 20 (ms) case:

Total Sample Points = 1.92 (MHz) x 1 x 1000 x 20 (ms) = 38400 (Points)

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 [Uplink E-UTRA/eMTC] [PRACH] 1.92 MHz [Uplink NB-IoT] 240 kHz [Prach NB-IoT]
Range	Value 1.92 MHz 3.84 MHz 7.68 MHz 15.36 MHz 23.04 MHz 30.72 MHz 1.92 MHz 240 kHz	SCPI F1M92 F3M84 F7M68 F15M36 F23M04 F30M72 Uplink NB-IoT Prach NB-IoT
Initial S/W Revision	A.14.00
Modified S/W Revision	A.19.00

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 is 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.

[Uplink NB-IoT]

Stand-Alone: 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.
Guard-Band: Frequency Offset is calculated by Coupled E-UTRA Carrier, Position vs Coupled E-UTRA Carrier and Offset from Coupled E-UTRA Carrier Edge.
In-Band: Frequency Offset is calculated by Coupled E-UTRA Carrier and In-Band RB Offset.

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
Modified S/W Revision	A.19.00

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/UPLINK NB-IoT/PRACH NBIoT]
Initial S/W Revision	A.14.00
Modified S/W Revision	A.19.00

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] 400 Ts [Uplink NB-IoT/PRACH NB-IoT]
Min	0
Max	400
Initial S/W Revision	A.14.00
Modified S/W Revision	A.19.00

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.

Baseband Filter off is for EVM optimized condition.
Baseband Filter on is for ACP optimized condition.

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 [E-UTRA/eMTC] [Basic Downlink] [PRACH NB-IoT] OFF [Uplink NB-IoT]
Initial S/W Revision	A.14.00
Modified S/W Revision	A.19.00

ACP Optimized Filter Type

[Uplink NB-IoT]

Choices: Standard | Narrow | Custom

Default: Standard

Narrow filter provides better spectrum performance, but EVM may degrade.

This setting is available when Baseband Filter is set to ON.

SCPI Command	[:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<channel>:ACPFILTer:TYPE STANdard\|NARRow\|CUSTom [:SOURce]:RADio:LTEFdd:WAVeform[:ARB]:CCARrier<channel>:ACPFILTer:TYPE?
SCPI Example
State Saved	Yes
Preset	STANdard
Initial S/W Revision	A.19.00

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 Even Frame Alignment

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

ACP Optimized Filter Type

Carrier Aggregation

Auto Carrier Aggregation Configuration

Primary Cell