Generate 5G NR Waveforms

Generate standard-compliant 5G NR downlink and uplink waveforms for test and measurement, simulation, and verification using nrWaveformGenerator.

When to Use

• Generate a 5G, NR, or New Radio waveform (DL: PDSCH, PDCCH, SSBurst, CSI-RS;

UL: PUSCH, PUCCH, SRS)

• Generate NR test model (TM) or fixed reference channel (FRC) waveforms
• Configure bandwidth, SCS, modulation, power, or multi-bandwidth-part layouts

When Not to Use

• Channel modeling or propagation — use nrCDLChannel, nrTDLChannel
• Receiver processing or decoding — use nrPDSCHDecode, nrDLSCHDecoder
• Link-level simulation end-to-end

API Choice

Do not use primitive-level functions (nrCarrierConfig + nrPDSCH + nrOFDMModulate) for waveform generation, and do not mix primitive config objects (nrPDSCHConfig, nrPUSCHConfig, nrCarrierConfig) with nrWaveformGenerator — use the nrWavegen* objects. nrWaveformGenerator handles channel multiplexing, power scaling, and OFDM modulation correctly. Full function catalog, property names, and the incompatible-object table: references/api-reference.md.

Core Workflow (custom DL/UL)

1. Create the carrier config with the simplified constructor (R2026a+),

which auto-sizes SCSCarriers, BandwidthParts, SSBurst/CORESET (DL), and a default PDSCH/PUSCH to the bandwidth:

cfg = nrDLCarrierConfig('FR1', 20, 30);  % DL: FR1, 20 MHz, 30 kHz SCS
cfg = nrULCarrierConfig('FR1', 20, 15);  % UL: FR1, 20 MHz, 15 kHz SCS

For DL, if the requested SCS differs from the default SSB numerology the constructor adds a dedicated SSB SCS carrier (e.g. nrDLCarrierConfig('FR1', 5, 30) adds a hidden 15 kHz carrier). Pre-R2026a, or to control the SCS-carrier count exactly, build manually with nrDLCarrierConfig (no args).

1. Customize only what the task requires (see the rule below). Set

non-defaults such as cfg.PDSCH{1}.Modulation = '64QAM';. Never overwrite a constructor-placed value with a different one (e.g. forcing NStartBWP = 0 when the constructor centered it) — that breaks the validated layout.

1. Generate — validateConfig checks structural rules but does not

catch channel conflicts (overlapping PDSCH/CSI-RS, CSI-RS/SSBurst); always run the generator, which returns the waveform and the resource-grid info:

[waveform, info] = nrWaveformGenerator(cfg);

What the simplified constructor builds is generation-ready as-is — an unedited nrDLCarrierConfig(fr, bw, scs) or nrULCarrierConfig(fr, bw, scs) generates for every FR1/FR2 bandwidth/SCS combination, so do not re-check what it set. This does not apply to the no-argument nrDLCarrierConfig / nrULCarrierConfig, whose defaults (15 kHz, Case A SSB, 52-RB PRBSet) must be resized by hand. One silent caveat: at 3 MHz / 15 kHz the SSB is wider than the 15-RB carrier, so the PBCH is punctured — this is expected; keep the SSB (details in Critical Rules). Check the Critical Rules for whatever you change or build by hand: a no-argument (manual) carrier, an edited NSizeGrid/BWP/CORESET/PRBSet, a BlockPattern override, an added SCS carrier or BWP (Point A centering), CSI-RS or PDCCH across BWPs, or 2 codewords (layers/DM-RS). Those edits cause the most generation failures.

Set Only What the Task Requires

Set every property the task requires — including parameters forced by a requested feature, even when the prompt never names them — and nothing else. For example, 2 codewords → NumLayers 5–8 → a DM-RS that supports more than 4 ports (see Critical Rules); a requested CSI-RS → CSIRS{1}.Enable = true (off by default). These are required, not over-config. SSBurst is already enabled by default, so a requested SS burst needs no Enable line.

Recipes and References

Open the reference that matches the task; each has copy-ready, verified code:

• Common single-carrier waveforms (Basic DL with dual-grid plot, Basic UL,

power spectrum): references/patterns.md

• Narrow-band 11-RB carriers, manual build only (5 MHz/30 kHz, 10 MHz/60 kHz).

The simplified constructor already handles these — skip this reference when you use it. Open it only for a no-argument build (pre-R2026a, or to avoid the auto-added SSB carrier), where the defaults fail and need NSizeGrid = 11, a disabled/rehomed SSB, a shrunk CORESET, AL1, and an explicit PRBSet: references/narrow-band-manual-config.md

• Multi-BWP / multi-numerology layouts:

references/multi-bwp-guidance.md

• Test models (TM) and fixed reference channels (FRC) — use the example

helper hNRReferenceWaveformGenerator(RC, BW, SCS) (e.g. 'DL-FRC-FR1-64QAM', 'NR-FR1-TM1.1'), then generateWaveform + displayResourceGrid. It is not on the path by default: first make it available with a portable setup (setupExample('5g/NRTestModelWaveformGenerationExample', ...) + copyfile + cd, or openExample) — never a hardcoded path, never a made-up namespaced name. Valid names, portable-setup block, and makeConfigWritable edits: references/test-models-and-frc.md

• Full API catalog + output structure (fields of info, correct property

names): references/api-reference.md

• Online documentation links:

references/documentation-links.md

Conventions

• After generating a waveform, unless the user asks for something specific:

1. Tell the user the waveform variable name and that it is in the workspace
2. Plot the resource grid from info.ResourceGrids(k).ResourceGridBWP (BWP-sized, one per BWP); use ResourceGridInCarrier only for a full-carrier view. The SS burst is a separate grid — when SSBurst.Enable is true and the SS burst is asked for, also plot info.ResourceGridSSBurst.ResourceGrid (it is not part of ResourceGridBWP)
3. Save the generation code as a .m script and open it in the MATLAB editor with edit('scriptName.m')

• Start with the simplified constructor nrDLCarrierConfig('FR1', bw, scs) when possible
• Correct property names: DMRSPower (not PowerDMRS), PTRSPower (not PowerPTRS), NSizeGrid (not NRB), ChannelBandwidth (not Bandwidth)
• SCSCarriers, BandwidthParts, CORESET, PDSCH, PUSCH are cell arrays — use {}; SSBurst is a direct object — use . not {}
• Use tiledlayout/nexttile for multi-panel figures; always label axes with units and include figure titles
• Comment non-obvious, interdependent choices (why a given NSizeGrid, why SSBurst is disabled, why a specific AggregationLevel) so the code explains itself

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