LTE TDD
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.
Auto Carrier Aggregation Configuration
This setting specifies the enable state of a carrier.
|
SCPI Command |
[:SOURce]:RADio:LTETdd:WAVeform[:ARB]:CCARrier<carrier>[:STATe] OFF|ON|0|1 [:SOURce]:RADio:LTETdd:WAVeform[:ARB]:CCARrier<carrier>[:STATe]? |
|
SCPI Example |
:RAD:LTET:WAV:CCAR OFF :RAD:LTET:WAV:CCAR? |
|
State Saved |
Yes |
|
Preset |
ON |
|
Initial S/W Revision |
A.14.00 |
Set the waveform generation length.
|
SCPI Command |
[:SOURce]:RADio:LTETdd:WAVeform[:ARB]:CCARrier<carrier>:LENGth <time> [:SOURce]:RADio:LTETdd:WAVeform[:ARB]:CCARrier<carrier>:LENGth? |
|
SCPI Example |
:RAD:LTET:WAV:CCAR:LENG 100 ms :RAD:LTET:WAV:CCAR:LENG? |
|
Notes |
Value is rounded into the boundary value of frames (10 ms) PRACH E-UTRA: 1 frame (10 ms) |
|
State Saved |
Yes |
|
Preset |
10 ms |
|
Min |
10 ms |
|
Max |
10240 ms [Uplink E-UTRA] 200 ms [PRACH E-UTRA] |
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Resolution |
10 ms [PRACH E-UTRA] |
|
Range |
[PRACH E-UTRA] 1 frame (10 ms) | 2 frames (20 ms) | 10 frames (100 ms) | 20 frames (200 ms) |
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Initial S/W Revision |
A.14.00 |
This setting returns the carrier type. This setting is automatically set when a carrier is added.
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SCPI Command |
[:SOURce]:RADio:LTETdd:WAVeform[:ARB]:CCARrier<carrier>:TYPE? |
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SCPI Example |
:RAD:LTET:WAV:CCAR:TYPE? |
|
Notes |
SCPI only, Query only Returns TDDULEUTRA|TDDPRACHEUTRA|CW |
|
State Saved |
No |
|
Preset |
TDDULEUTRA |
|
Range |
Uplink E-UTRA | PRACH E-UTRA | Continuous Wave |
|
Initial S/W Revision |
A.14.00 |
The parameters in the Baseband group set the baseband settings of a carrier.
This parameter sets the mode of oversampling rate control.
|
SCPI Command |
[:SOURce]:RADio:LTETdd:WAVeform[:ARB]:CCARrier<carrier>:OSRatio:AUTO[:STATe] OFF|ON|0|1 [:SOURce]:RADio:LTETdd:WAVeform[:ARB]:CCARrier<carrier>:OSRatio:AUTO[:STATe]? |
|
SCPI Example |
:RAD:LTET:WAV:CCAR:OSR:AUTO OFF :RAD:LTET:WAV:CCAR:OSR:AUTO? |
|
State Saved |
Yes |
|
Preset |
ON |
|
Initial S/W Revision |
A.14.00 |
This parameter sets oversampling ratio of waveform generation. This value is used when Auto Oversampling Ratio is Off.
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.
|
SCPI Command |
[:SOURce]:RADio:LTETdd:WAVeform[:ARB]:CCARrier<carrier>:OSRatio <integer> [:SOURce]:RADio:LTETdd:WAVeform[:ARB]:CCARrier<carrier>:OSRatio? |
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SCPI Example |
:RAD:LTET:WAV:CCAR:OSR 2 :RAD:LTET:WAV:CCAR:OSR? |
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Dependencies |
This value is used when Auto Oversampling Rate Mode is Off |
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State Saved |
Yes |
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Preset |
2 |
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Min |
1 |
|
Max |
7 |
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Initial S/W Revision |
A.14.00 |
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.
For multi-carrier waveforms, the Base Sampling Rate = 30.72 MHz.
|
SCPI Command |
[:SOURce]:RADio:LTETdd:WAVeform[:ARB]:CCARrier<carrier>:SRATe:BASE? |
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SCPI Example |
:RAD:LTET:WAV:CCAR:SRAT:BASE? |
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Notes |
Query only |
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State Saved |
No |
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Preset |
F15M36 |
|
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 |
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Initial S/W Revision |
A.14.00 |
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:LTETdd:WAVeform[:ARB]:CCARrier<carrier>:SAMPles:COUNt? |
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SCPI Example |
:RAD:LTET:WAV:CCAR:SAMP:COUN? |
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Notes |
Query only |
|
State Saved |
No |
|
Preset |
153600 |
|
Initial S/W Revision |
A.14.00 |
[Uplink TDD]
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, Cell ID, Uplink Downlink Configuration, Special Subframe Configuration, and Cyclic Prefix.
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, and the parameters (Uplink Downlink Configuration, Special Subframe Configuration, and Cyclic Prefix) on the secondary cells same value of the primary cell as read-only parameter.
If Auto Carrier Aggregation Configuration is set to off, auto configuration does not work.
|
SCPI Command |
[:SOURce]:RADio:LTETdd:WAVeform[:ARB]:CCARrier<carrier>:FREQuency:OFFSet <freq> [:SOURce]:RADio:LTETdd:WAVeform[:ARB]:CCARrier<carrier>:FREQuency:OFFSet? |
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SCPI Example |
:RAD:LTET:WAV:CCAR:FREQ:OFFS 1000000 :RAD:LTET:WAV:CCAR:FREQ:OFFS? |
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State Saved |
Yes |
|
Preset |
0 Hz |
|
Initial S/W Revision |
A.14.00 |
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:LTETdd:WAVeform[:ARB]:CCARrier<carrier>:POWer <rel_ampl> [:SOURce]:RADio:LTETdd:WAVeform[:ARB]:CCARrier<carrier>:POWer? |
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SCPI Example |
:RAD:LTET:WAV:CCAR:POW -20 :RAD:LTET:WAV:CCAR:POW? |
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State Saved |
Yes |
|
Notes |
Unit in GUI: dB |
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Preset |
0 dB |
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Min |
-60 dB |
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Max |
0 dB |
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Resolution |
0.001 dB |
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Initial S/W Revision |
A.14.00 |
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:LTETdd:WAVeform[:ARB]:CCARrier<carrier>:TIMing:OFFSet <time> [:SOURce]:RADio:LTETdd:WAVeform[:ARB]:CCARrier<carrier>:TIMing:OFFSet? |
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SCPI Example |
:RAD:LTET:WAV:CCAR:TIM:OFFS 0.1ns :RAD:LTET:WAV:CCAR:TIM:OFFS? |
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Notes |
Not used for CW Carrier Unit in GUI: s |
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State Saved |
Yes |
|
Preset |
0.000 us |
|
Min |
0.000 us |
|
Max (LP) |
Minimum (Waveform Generation Length – 1 ns or 10 ms – 1 ns) (us) |
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Initial S/W Revision |
A.14.00 |
Sets the initial phase of the carrier.
|
SCPI Command |
[:SOURce]:RADio:LTETdd:WAVeform[:ARB]:CCARrier<carrier>:INITial:PHASe <integer> [:SOURce]:RADio:LTETdd:WAVeform[:ARB]:CCARrier<carrier>:INITial:PHASe? |
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SCPI Example |
:RAD:LTET:WAV:CCAR:INIT:PHAS 10 :RAD:LTET:WAV:CCAR:INIT:PHAS? |
|
Notes |
Not used for CW Carrier Unit in GUI: deg |
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State Saved |
Yes |
|
Preset |
0 |
|
Min |
0 |
|
Max |
359 |
|
Initial S/W Revision |
A.14.00 |
This section describes the settings of Spectrum Control.
Set the clipping (limit) level of the I/Q waveform before filtering.
|
SCPI Command |
[:SOURce]:RADio:LTETdd:WAVeform[:ARB]:CCARrier<carrier>:CLIPping:PRE <real> [:SOURce]:RADio:LTETdd:WAVeform[:ARB]:CCARrier<carrier>:CLIPping:PRE? |
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SCPI Example |
:RAD:LTET:WAV:CCAR:CLIP:PRE 80 :RAD:LTET:WAV:CCAR:CLIP:PRE? |
|
Notes |
Value is in percent [%], 100 means 100 % 100 % means "no clipping" Unit in GUI: % |
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State Saved |
Yes |
|
Preset |
100 |
|
Min |
10 |
|
Max |
100 |
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Resolution |
0.1 |
|
Initial S/W Revision |
A.14.00 |
Set the clipping (limit) level of the I/Q waveform after filtering.
|
SCPI Command |
[:SOURce]:RADio:LTETdd:WAVeform[:ARB]:CCARrier<carrier>:CLIPping:POST <real> [:SOURce]:RADio:LTETdd:WAVeform[:ARB]:CCARrier<carrier>:CLIPping:POST? |
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SCPI Example |
:RAD:LTET:WAV:CCAR:CLIP:POST 80 :RAD:LTET:WAV:CCAR:CLIP:POST? |
|
Notes |
Value is in percent [%], 100 means 100 % 100 % means "no clipping" Unit in GUI: % |
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State Saved |
Yes |
|
Preset |
100 |
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Min |
10 |
|
Max |
100 |
|
Resolution |
0.1 |
|
Initial S/W Revision |
A.14.00 |
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:LTETdd:WAVeform[:ARB]:CCARrier<carrier>:SROLloff:LENGth <integer> [:SOURce]:RADio:LTETdd:WAVeform[:ARB]:CCARrier<carrier>:SROLloff:LENGth? |
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SCPI Example |
:RAD:LTET:WAV:CCAR:SROL:LENG 10 :RAD:LTET:WAV:CCAR:SROL:LENG? |
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State Saved |
Yes |
|
Notes |
Unit in GUI: Ts |
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Preset |
0 |
|
Min |
0 |
|
Max |
400 |
|
Initial S/W Revision |
A.14.00 |
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:LTETdd:WAVeform[:ARB]:CCARrier<carrier>:BFILter[:STATe] OFF|ON|0|1 [:SOURce]:RADio:LTETdd:WAVeform[:ARB]:CCARrier<carrier>:BFILter[:STATe]? |
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SCPI Example |
:RAD:LTET:WAV:CCAR:BFIL ON :RAD:LTET:WAV:CCAR:BFIL? |
|
State Saved |
Yes |
|
Preset |
ON |
|
Initial S/W Revision |
A.14.00 |
The Carrier Aggregation node holds the settings of carrier aggregation.
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, Cell ID, Uplink Downlink Configuration, Special Subframe Configuration, and Cyclic Prefix.
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, and the parameters (Uplink Downlink Configuration, Special Subframe Configuration, and Cyclic Prefix) on the secondary cells same value of the primary cell as read-only parameter.
If Auto Carrier Aggregation Configuration is set to off, auto configuration does not work.
|
SCPI Command |
[:SOURce]:RADio:LTETdd:WAVeform[:ARB]:CCARrier<carrier>:CAConfig:AUTO[:STATe] OFF|ON|0|1 [:SOURce]:RADio:LTETdd:WAVeform[:ARB]:CCARrier<carrier>:CAConfig:AUTO[:STATe]? |
|
SCPI Example |
:RAD:LTET:WAV:CCAR:CAC:AUTO OFF :RAD:LTET: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 |
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:LTETdd:WAVeform[:ARB]:CCARrier<carrier>:PCELl[:STATe] OFF|ON|0|1 [:SOURce]:RADio:LTETdd:WAVeform[:ARB]:CCARrier<carrier>:PCELl[:STATe]? |
|
SCPI Example |
:RAD:LTET:WAV:CCAR:PCEL ON :RAD:LTET: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 |
The buttons of carrier configuration tools may appear when a carrier is configured. Refer to specific carrier sections for more details of the carrier configuration buttons. The configuration buttons are configured differently by each carrier.