Cyclic prefix, live — computed while you read

5G Systems Notes · Concept map · Cyclic prefix · live ← the written note · Simulator ↗ · Hub

computed at page load   The working half of Cyclic prefix. That page is the explanation; this one is what the simulator can compute about it, kept apart so the written note stays a document rather than a control panel.

In one line. Every number below is produced by 5G Simulation/src/nrsim/ while this page renders, from the same code its tests run against — so nothing here can drift from what the written note says.

The prefix at every numerology

N_CP in units of T_c, in microseconds, and as a share of the slot. What collapses with μ is the absolute length — 4.69 µs at 15 kHz, 0.59 at 120 kHz, 0.07 at 960 kHz. The share is near 7 % across FR1 and the low FR2 spacings but is not constant: it reaches 9.6 % at 960 kHz, because every half-subframe still begins with one longer prefix and there are 64 slots in it rather than one.

Widget not found: sim_show

What that costs an FR2 carrier

The prefix is what a receiver spends on delay spread. At FR2's 120 kHz it is roughly 0.6 µs, which is why mmWave needs the short delay spread of a line-of-sight or near-line-of-sight path.

Widget not found: sim_show

Where this comes from

Computed, not transcribed. ../widgets/sim_show.py imports the simulator's specification and parameter tiers inside the engine process. Those tiers are stdlib-only precisely so this is possible — the engine's own environment has no NumPy, which is also why anything from the physical layer (LDPC, HARQ, the waveform) cannot appear here and is offered as a nrsim show command on the written note instead.

This page is generated by tools/make_live_pages.py from LIVE_FOR in that widget. To change what appears, edit the declaration, not this file.

5G Systems Notes · Concept map · Cyclic prefix · live ← the written note · Simulator ↗ · Hub