Transient Period (5G NR/5G-Advanced)

The Transient Period (uplink only) parameter group is used to decide when the transient period starts and ends and whether the transient period is excluded from 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. calculation. See TS Technical Specification 38.521-1, Section 6.4.2.1a.3 and TS 38.521-1 Annex, Section 4.7 for more information on EVM test including symbols with transient period.

Mode - For each slot, the VSA software detects symbols with transient periods and excludes the transient periods from the EVM calculation based on the Mode selection. Proper exclusion depends on properly setting the transient period Length and Power Change Threshold.

None - Use all symbols for EVM calculation without excluding transient period.

Exclude Symbols - Exclude symbols with transient period.

Exclude Transient Period - Include symbols with transient period, but exclude transient by EVM WINDOW (CP 1) Contention period, or 2) Cyclic prefix-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., used for conformance testing) or TIME (DFT discrete Fourier transform-s-OFDM). See Transform Precoding for more information.

Default: None

Length - Sets the expected length (tp) and location (tp_start)of the transient period, for the purpose of detecting and excluding the transient period from EVM calculations. tp_start denotes the start position of the exclusion window relative to the beginning of the symbol, as shown in Figure E.4.7-1 of TS 38.521-1 Annex 4.7. See TS 38.521-1 Table 6.4.2.1a.3-1 and Annex 4.7 for more information.

2 µs - Configures the VSA for a 2 µs reported transient period (tp = 2 µs, tp_start = -0.5 µs)

4 µs - Configures the VSA for a 4 µs reported transient period (tp = 4 µs, tp_start = -1 µs)

7 µs - Configures the VSA for a 7 µs reported transient period (tp = 7 µs, tp_start = -2.7 µs)

Default: 2 µs

Power Change Threshold - Sets the threshold for detecting whether the power is changed from last slot to next slot.