Basic LTE/LTE-A
Choice: On | Off
Default: On
Double-click or use the drop-down menu to control the operating state of the carrier.
Choices: 1 slot (0.5 ms) | 2 slots (1.0 ms) | … | 18 slots (9.0 ms) | 19 slots (9.5 ms) | 1 frame (10 ms) | 2 frames (20 ms) | 3 frames (30 ms) | 4 frames (40 ms)
Default: 1 frame (10 ms)
Double-click or use the drop-down menu to select the waveform generation length.
When the waveform generation length or offset is set, Waveform Generation Length + Waveform Generation Offset <= 1 frame (10 ms) is automatically satisfied by the software.
When the waveform generation length is longer than 1 frame, the waveform generation offset is limited to 0 slot (0.0 ms).
Range: 1 to 1024 ms
Default: 1 frame
Set the waveform generation length.
Range: 0 to 19 slots
Default: 0 slot
Sets the waveform generation offset. This parameter is available for basic carriers only.
When the waveform generation length or offset is set, Waveform Generation Length + Waveform Generation Offset <= 1 frame (10 ms) is automatically satisfied by the software.
If the Waveform Generation Length parameter is set less than the Transmission Configuration Length, the value of Transmission Configuration Length is changed to be ≤Waveform Generation Length. In summary, the relation between Transmission Configuration Length and Waveform Generation Length is that the Transmission Configuration Length ≤Waveform Generation Length. (For more information on the Transmission Configuration Length parameter refer to the Channel Setups Advanced LTE TDD UL or and DL topics or the Channel Setups Advanced LTE-A TDD UL or and DL topics.)
While the long waveform is playing, the following signal or data values are generated sequentially.
Downlink:
SFN in BCH is automatically counted up until the end of the waveform.
HARQ Process scheme in DL-SCH is automatically updated until the end of the waveform.
Payload data in DL-SCH is sequentially used for transport block until the end of the waveform.
HARQ Process Index and New Data Indicator (NDI) in DCI contents are automatically updated until the end of the waveform.
Uplink:
HARQ Process scheme in UL-SCH is automatically updated until the end of the waveform.
Payload data in UL-SCH is sequentially used for transport block until the end of the waveform.
Figure. Frame Structure type 2 (for 5 ms switch-point periodicity)
Choices: Auto, 1, 2
Default: Auto
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 results in a more completely filtered image, but also uses more waveform memory by increasing the number of waveform points. If AUTO is selected, the signal generator automatically selects the optimized oversampling ratio for the current signal setup.
Displays the Base Sampling Rate of the signal. This cell can not be edited.
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.
For multicarrier waveforms, the Base Sampling Rate = 30.72 MHz.
View the waveform length, displayed in points. This cell cannot be edited.
The Total Sample Points value is automatically determined based on the oversampling ratio. Using a larger oversampling ratio results in a more completely filtered image, but also uses more waveform memory by increasing the number of waveform points.
Total Sample Points = (Waveform Generation (ms) * Oversampling Ratio * Base Sampling Rate)
Default: 0.000000 Hz
Set the frequency offset of 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.
For single carrier configurations, the following table shows the maximum frequency offset:
| Maximum Frequency Offset | System Bandwidth | |||||
|---|---|---|---|---|---|---|
| Maximum Arb Sample Clock (RF Bandwidth) | 1.4 MHz | 3 MHz | 5 MHz | 10 MHz | 15 MHz | 20 MHz |
| 75 MHz (60 MHz) | 29.3 MHz | 28.5 MHz | 26.72 MHz | 20.54 MHz | 22.04 MHz | 15.36 MHz |
| 100 MHz (80 MHz) | 39.3 MHz | 38.5 MHz | 37.5 MHz | 35 MHz | 32.5 MHz | 30 MHz |
| 125 MHz (100 MHz) | 49.3 MHz | 48.5 MHz | 47.5 MHz | 45 MHz | 42.5 MHz | 40 MHz |
| 150 MHz (120 MHz) | 59.3 MHz | 58.5 MHz | 57.5 MHz | 55 MHz | 52.5 MHz | 46.08 MHz |
| 200 MHz (160 MHz) | 79.3 MHz | 78.5 MHz | 77.5 MHz | 75 MHz | 72.5 MHz | 70 MHz |
For multiple carrier configurations, the following table shows the maximum frequency offset:
| Maximum Frequency Offset | System Bandwidth | |||||
|---|---|---|---|---|---|---|
| Maximum Arb Sample Clock (RF Bandwidth) | 1.4 MHz | 3 MHz | 5 MHz | 10 MHz | 15 MHz | 20 MHz |
| 75 MHz (60 MHz) | 15.36 MHz | |||||
| 100 MHz (80 MHz) | 30.72 MHz | 30 MHz | ||||
| 125 MHz (100 MHz) | 46.08 MHz | 45 MHz | 42.5 MHz | 40 MHz | ||
| 150 MHz (120 MHz) | 46.08 MHz | |||||
| 200 MHz (160 MHz) | 76.8 MHz | 75 MHz | 72.5 MHz | 70 MHz | ||
Range: -60.000 to 0.000 dB
Default: 0.000 dB
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 Signal Generator node.
The carrier power level set with this parameter determines how the total RF power level (set with the Amplitude parameter in the Instrument node) is shared by the carriers in a multiple carrier configuration. The power, set in dB, is relative to the power, in dB, of the other carriers.
Example: Assume a two-carrier configuration with the RF power level set at -10 dBm in the instrument node. If Carrier 1 is set to 0 dB and Carrier 2 is set to 0 dB, then each carrier will be transmitted with the same power level. This means that each carrier will be transmitted at -13 dBm to maintain the total power output by the instrument at -10 dBm.
When Power Definition Type is set to Total Power, the RSTP is automatically calculated from the Amplitude setting in the Instrument node, the Power setting in the Component Carrier node, and each carrier's signal settings.
When Power Definition Type is set to RSTP, the Amplitude setting in the Instrument node and the Power setting in the Component Carrier node are automatically calculated and read-only.
Range: 0.000 to minimum (waveform generation length - 1 ns or 10 ms - 1 ns) (us)
Default: 0.000 (us)
Specifies the length of timing offset. The maximum value of the range depends of Waveform Generation Length.
If the Timing Offset cannot be divided by sampling period (1 / Base Sampling Rate), the data is generated by the linear interpolation process.
Timing offset shifts the waveform relative to its original position and the Event 1 frame trigger marker signal. Each offset increment represents a period of time equal to the inverse value of the sampling frequency (see table below). As the waveform bit stream is shifted within a frame, the leftover bits wrap around to occupy the time between the original position and the offset value. This is advantageous in a multicarrier configuration because you can vary the timing offset of each carrier to reduce the probability of all carriers adding in phase and minimize the crest factor in the composite waveform. In a single carrier configuration, the timing offset has no effect on the crest factor, and therefore, should be set to 0.
|
Sampling Frequency |
Time Value per Offset Increment (1/sampling frequency) |
Channel Configuration (Bandwidth and Resource Blocks) |
|---|---|---|
|
1.92 MHz |
520.8 ns |
1.4 MHz, 6 RB |
|
3.84 MHz |
260.4 ns |
3 MHz, 15 RB |
|
7.68 MHz |
130.2 ns |
5 MHz, 25 RB |
|
15.36 MHz |
65.1 ns |
10 MHz, 50 RB |
|
23.04 MHz |
43.4 ns |
15 MHz, 75 RB |
|
30.72 MHz |
32.55 ns |
20 MHz, 100 RB |
|
30.72 MHz |
32.55 ns |
Multicarrier |
Range: 0 to 359 degrees
Default: 0 degrees
Set the initial phase of the carrier.
Range: 0 to 400 Ts
Default: 0 Ts
Windowing is used in the Signal Studio for 3GPP LTE software to reduce spurious signal generation between symbols.
Symbol Rolloff sets the windowing length in Basic Time Units.
Basic Time Unit (Ts) = 1/(15000 x 2048) seconds
Choice: On | Off
Default: On
Double-click or use the drop-down menu to turn the baseband filter on or off. Turning the baseband filter off is not recommended.
Range: 10 to 100%
Default: 100%
Set the clipping (limit) level of the I/Q waveform before filtering. (100.0% = no clipping)
Range: 10 to 100%
Default: 100%
Set the clipping (limit) level of the I/Q waveform after filtering. (100.0% = no clipping)
Choice: Inter-band 1 | Inter-band 2
Default: Inter-band 1
Double-click or use the drop-down menu to set the inter-band hardware.
