5G/NR Frame Structure
There have been lengthy discussions on frame structure both in academia and in 3GPP and now we have pretty clear agreements on what a NR (5G) radio body would appearance, like In this page I will describe on NR Frame Structure that is laid out in 3GPP specifications. If you're interested in the ones lengthy discussions and histories about show those specification came out for your personal attraction and study.
5G/NR Numerology and Sub-Carrier Spacing:
Numerology: corresponds to one sub carrier spacing inside the frequency domain. By go up a reference sub carrier spacing by an integer N, special numerology may be defined.
The numerology is based on exponentially scalable sub-service (sub-carrier spacing) Δf = 2μ × 15 kHz with μ=0, 1, 3, 4 for Primary Synchronize Signal, Secondary Synchronize Signal & PBCH and μ=0, 1, 2, 3 for other channels. Normal CP is supported for all sub-service (sub-carrier) spacing, Extended CP is
Supported for μ=2. 12 consecutive sub-carriers shape a Physical Resource Block (PRB). Up to 275 PRBs are supported on a provider.
Frame and Subframe length:
In 5G/NR Downlink and uplink transmissions are organized into Radio frames with 10 ms length, together with ten 1 ms sub frames. Each radio frame is divided into two equally-sized half-radio frames of 5 sub frames each. The slot duration is 14 symbols with Normal Cyclic Prefix and 12 symbols with Extended Cyclic Prefix, and scales in time as a function of the used sub-carrier spacing so that there is continually an integer no. of slots in a sub frame.
Supportive transmission numerologies:
Every numerology can't be used for every physical channel and signals. That is, there is a specific numerologies which are used simplest for a certain kind of physical channels despite the fact that majority of the numerologies may be used any kind of physical channels. Following table is shows which numerology can be used for which physical channel.
5G/NR OFDM Symbol Duration:
As you know that there are multiple numerologies are using in 5G/NR. So the ofdm symbol durations also are changed as per numerology use in physical layer. For e.g. if Numerology 0 is use the ofdm symbol duration is 66.67µs. But if Numerology 4 is use then the ofdm symbol duration is decrease and it would be 4.17µs. please go through with below table for more clarity.
5G/NR Numerology Sampling Time:
if we take an example of 15Khz sub-carrier the sampling rate will be Nf=2048. And sampling time is Tc=32.6ns. or if we take an example of 480Khz sub-carrier the sampling rate will be Nf=4096. And sampling time is Tc=0.509ns.
5G/NR Radio Frame Structure:
[Normal Cyclic Prefix, Numerology=0]: In this configuration, a sub-frame has one (1) slot, it means a radio frame [RF] consists of 10 slots in it. The numbers of OFDM symbols present in a slot is 14.
[Normal Cyclic Prefix, Numerology=1]:
In this configuration, a sub-frame has two (2) slots, it means a radio frame [RF] consists of 20 slots in it. The numbers of OFDM symbols present in a slot is 14.
[Normal Cyclic Prefix, Numerology=2]:
In this configuration, a sub-frame has four (4) slots, it means a radio frame [RF] consists of 40 slots in it. The numbers of OFDM symbols present in a slot is 14.
[Normal Cyclic Prefix, Numerology=3]:
In this configuration, a sub frame has Eight (8) slots, it means a radio frame [RF] consists of 80 slots in it. The numbers of OFDM symbols present in a slot is 14.
[Normal Cyclic Prefix, Numerology=4]:
In this configuration, a sub frame has Sixteen (16) slots, it means a radio frame [RF] consists of 160 slots in it. The numbers of OFDM symbols present in a slot is 14.
[Extended Cyclic Prefix, Numerology=2]:
In this configuration, a sub frame has four (4) slots, it means a radio frame [RF] consists of 40 slots in it. The numbers of OFDM symbols present in a slot is 12.
