### 5G NR: Numerologies and Frame Structure

Supported Transmission Numerologies
-       A numerology is defined by sub-carrier spacing and Cyclic-Prefix overhead.
-       In LTE there is only one subcarrier spacing which is 15kHz where as in the case of 5G NR multiple subcarrier spacings are defined. Multiple subcarrier spacings can be derived by scaling a basic subcarrier spacing by an integer N.
-       The numerology used can be selected independently of the frequency band although it is assumed not to use a very low subcarrier spacing at very high carrier frequencies. Flexible network and UE channel bandwidth is supported.
-       The numerology is based on exponentially scalable sub-carrier spacing deltaF = 2µ × 15 kHz with µ = {0,1,3,4} for PSS, SSS and PBCH and µ = {0,1,2,3} for other channels.
-       Normal CP is supported for all sub-carrier spacings, Extended CP is supported for µ=2.
-       12 consecutive sub-carriers form a physical resource block (PRB). Up to 275 PRBs are supported on a carrier.
-       Resource defined by one subcarrier and one symbol is called as resource element (RE).
-       The following table summarizes all supported numerologies in 3GPP Release 15.

Numerologies in detail:
µ = 0:

µ = 1:

µ = 2:

µ = 3:

µ = 4:

µ = 5:

Frame Structure
-       Downlink and uplink transmissions are organized into frames with 10ms duration, consisting of 10 subframes, 1ms each. Each frame is divided into 2 equally-sized half-frames of 5 subframes each.

-       Other than the first OFDM symbol in every 0.5ms, all OFDM symbols within 0.5ms have the same size.

Reference: 3GPP TS 38.211, TS 38.300, TR 38.802, TR 38.912