Modulation and Coding (PUSCH, 6GR)
The group of the PUSCH tab. All parameters are auto-coupled — see Auto and Manual Parameter Coupling.
Five of the settings in this group — MCS, Redundancy Version, Modulation, Coding Rate, and Transport Block Size — are laid out as a grid with a and a column. The second column is unavailable unless the channel carries two codewords; see Number of Codewords / Layers.
Transform Precoding - Enables transform precoding (DFT discrete Fourier transform-s-OFDM Orthogonal Frequency Division Multiplexing: OFDM employs multiple overlapping radio frequency carriers, each operating at a carefully chosen frequency that is Orthogonal to the others, to produce a transmission scheme that supports higher bit rates due to parallel channel operation. OFDM is an alternative tranmission scheme to DSSS and FHSS.). When enabled, CDM Group(s) w/o Data is fixed at 2 (per 3GPP TS Technical Specification 38.214 §6.2.2), the MCS Table choices change to the transform-precoding tables, and tp-pi2BPSK becomes available.
Default: Cleared
MCS modulation and coding scheme Table - Selects the modulation and coding scheme table. 3GPP splits the PUSCH tables on transform precoding (TS 38.214 §6.1.4.1), so the choices depend on Transform Precoding. 1024QAM is defined for the downlink only and never appears here.
- Table 64QAM - The 64QAM MCS table, per 3GPP TS 38.214 Table 5.1.3.1-1. Transform precoding off only.
- Table 256QAM - The 256QAM MCS table, per Table 5.1.3.1-2. Offered in both states.
- Table 64QAM LowSE - The 64QAM low spectral efficiency MCS table, per Table 5.1.3.1-3. Transform precoding off only.
- Table 64QAM(TP) - The 64QAM MCS table for transform precoding, per Table 6.1.4.1-1. Transform precoding on only.
- Table 64QAM LowSE(TP) - The 64QAM low spectral efficiency MCS table for transform precoding, per Table 6.1.4.1-2. Transform precoding on only.
Default: Table 64QAM
Choices: with transform precoding off, Table 64QAM, Table 256QAM, Table 64QAM LowSE; with it on, Table 256QAM, Table 64QAM(TP), Table 64QAM LowSE(TP)
tp-pi2BPSK - Shares the MCS Table row, appearing beside it only while Transform Precoding is enabled and a transform-precoding MCS table is selected. Enables π/2 BPSK Binary phase shift keying - A type of phase modulation using 2 distinct carrier phases to signal ones and zeros. modulation (the 3GPP field of the same name, applied by TS 38.214 §6.1.4.1). When set, the lowest MCS indexes of Table 64QAM(TP) select π/2-rotated BPSK rather than QPSK Quadrature phase shift keying, which changes the reported Modulation.
Default: Cleared
xOverhead - Sets the number of resource elements per resource block reserved for overhead when computing the transport block size.
Default: 0
Choices: 0, 6, 12, 18
MCS - Sets the modulation and coding scheme index within the selected table, per codeword. Both codewords are read through the same MCS Table, because 3GPP configures the MCS table per channel rather than per codeword.
Default: 0
Range: 0 to 31
Redundancy Version - Sets the redundancy version per codeword, which selects which part of the encoded transport block was transmitted (3GPP TS 38.212). Value 0 is an initial transmission. This affects the decoded bits rather than the constellation, so an incorrect value shows up as a failed CRC Cyclic Redundancy Check rather than as degraded EVM Error vector magnitude (EVM): A quality metric in digital communication systems. See the EVM metric in the Error Summary Table topic in each demodulator for more information on how EVM is calculated for that modulation format.. The two codewords are managed independently, so their values need not match.
Default: 0
Range: 0 to 3
Modulation / Coding Rate - (Read-only) Report the modulation format and coding rate implied by the MCS table and index, per codeword (QPSK and 120/1024 at MCS 0).
Transport Block Size - (Read-only) Reports the transport block size, in bits, per codeword. Computed per 3GPP TS 38.214 from the current MCS and resource allocation, the DMRS overhead, and xOverhead.
See Also
