PRACH Channel Setup
1. PRACH Time-domain Resource
Configuration Table
Choices: FR1 - Paired Spectrum/Supplementary uplink | FR1 - Unpaired Spectrum for FR1; FR2 - Unpaired Spectrum for FR2.
Default: FR1 - Paired Spectrum/Supplementary uplink
Select the PRACH Configuration Table.
Configuration Index
Range: -1 to 262 for FR1 Unpaired Spectrum; -1 to 255 for others.
Default: 16
Enter the PRACH Configuration Index.
Enter -1 means user defined PRACH, not restricted to the configuration table.
When recalling a settings file (*.scp) with N7631C v2.0, the configuration index is automatically set to -1 for backwards compatibility.
PRACH Format
Choices: 0 | 1 | 2 | 3 | A0 | A1 | A2 | A3 | B1 | B2 | B3 | B4 | C0 | C2
Default: 0
Select the PRACH Format.
The format A0 is removed in the latest standard. It is kept in our Signal Studio following the old version (38.211 v1.2).
Frame Period
Display the Frame Period determined by the configuration table and configuration index, corressponding to the 'x' in the table.
Frame Offset
Display the Frame Offset determined by the configuration table and configuration index, corressponding to the 'y' in the table.
Subframe Index
Range: 0 to 9
Default: 0
Set the subframe index of PRACH when PRACH format is not 0,1,2,3.
Symbol Start
Range: Based on the subcarrier spacing of PRACH
Default: 0
Set the symbol start of PRACH when PRACH format is not 0,1, 2, 3.
Number of PRACH slots within a subframe
Display the Number of PRACH slots within a subframe (60 kHz slot) determined by the configuration table and configuration index.
Number of time-domain PRACH occasions within a PRACH slot
Display the Number of time-domain PRACH occasions with in a PRACH slot determined by the configuration table and configuration index.
PRACH duration
Display the PRACH duration determined by the configuration table and configuration index.
2. PRACH Frequency-domain Resource
Subcarrier Spacing for PRACH
Choices: 1.25 kHz | 5 kHz | 15 kHz | 30 kHz | 60 kHz | 120 kHz
Default: 1.25 kHz
Select the subcarrier spacing of the PRACH.
The valid choices are based on the PRACH format, see more information in Table 6.3.3.1-1 and 6.3.3.1-2 of 38.211.
-
When format is 0, 1, 2, the Subcarrier Spacing for PRACH can only be 1.25 kHz;
-
When format is 3, the Subcarrier Spacing for PRACH can only be 5 kHz;
-
When format is A0…C2, the Subcarrier Spacing for PRACH can be {15 kHz, 30 kHz, 60 kHz, 120 kHz}
Active Uplink BWP
Set the Active Uplink BWP parameters used for PRACH transmission.
Numerology
Choices: u = 0: 15 kHz | u = 1: 30 kHz | u = 2: 60 kHz Normal CP | u = 2: 60 kHz Extended CP for FR1; u = 2: 60 kHz Normal CP | u = 2: 60 kHz Extended CP | u = 3: 120 kHz | u = 4: 240 kHz for FR2.
Default: u = 1: 30 kHz
Select the numerology for current BWP.
If selected numerology is not enabled in the Resource Grid under Carrier node, and error will occur.
RB Offset (N_BWP_start)
Range: N_grid_start to (N_grid_start + N_grid_size - 1)
Default: 0
Set the RB offset of the BWP relative to CRB0.
RB Number (N_BWP_size)
Range: 1 to (N_grid_start + N_grid_size - N_BWP_start)
Default: 273
Set the RB number of the BWP.
Msg1 Frequency Start (n_RA_start)
Range: 0 to RB Number of BWP.
Default: 0
Set the Msg1 Frequency Start (n_RA_start) for PRACH signal generation.
Msg1 FDM
Choices: 1 | 2 | 4 | 8
Default: 1
Enter the number of PRACH transmission occasions FDMed in one time instance.
3. PRACH Sequence Generation
PRACHRoot Sequence Index
Range: 0 to 837 for LRA = 839; 0 to 137 for LRA = 139.
Default: 0
Set the higher-layer parameter prach-RootSequenceIndex used for sequence generation.
Restricted Set Config
Choices: Unrestricted set | Restricted set type A | Restricted set type B
Default: Unrestricted set
Select the Restricted Set Config.
It is only visible when PRACH format is 0,1, 2, or 3.
Zero Correlation Zone Config
Default: 0
Set the Zero Correlation Zone Config.
The range is based on the subcarrier spacing of PRACH and restricted set config.
L_RA
Choces: 139 |1151 for 15kHz; 139 | 571 for 30kHz; Fixed to 139 for 60kHz and 120kHz; Fixed to 839 for 1.25kHz and 5kHz.
Default: 839
Set the L_RA value of PRACH.
N_CS
Display the N_CS value of PRACH.
Add Burst
Click the Add Burst button to add a Burst to the setup table. The Burst is inserted above the currently selected Burst in the table.
Remove Burst
Click the Remove Burst button to delete the currently selected Burst from the setup table. Initial Burst in PRACH cannot be removed.
Copy Burst
Click the Copy Burst button to copy the currently selected Burst to the last row of the setup table.
Multi-Burst Configuration Table
Use this table to add, remove, and copy multiple PRACH bursts. For each burst, you can edit any of the non-grayed parameters.
For time-domain candidate location of each PRACH burst, you can edit Frame Offset, Subframe Index (Slot Index), n_RA_t, and n_RA_slot, but candidate values should be determined by current configuration index.
For frequency-domain candidate location of each PRACH burst, the range of n_RA_f is 0 to (Msg1 FDM - 1).
For each PRACH burst, use Preamble Index and PRACH Root Sequence Index to determine the Root Sequence Index and Cyclic Shift Index. You can also edit Root Sequence Index and Cyclic Shift Index if Preamble Index is set to -1.
RA_RNTI is a read-only parameter for your information only.
You can also set the Configuration Index to -1 for a user-defined PRACH. In this case, you can specify PRACH Format, Symbol Start, Subframe Index (slot index), and n_RA_f, but the following will be true:
-
Frame Period is fixed to 1
-
Number of PRACH slots is fixed to 2
-
Number of time-domain PRACH occasions within a PRACH slot is fixed to 1
When recalling a settings file (*.scp) with N7631C v2.0, the configuration index is automatically set to -1 for backwards compatibility.