NR - the New Revolution

Let’s begin a new learning & experiential too.

I am starting a new chapter from today “NR - the New Revolution”. With my limited understanding of this trendy tech, I will sharing the learning in most simplest way possible.

The goal is to make this tech as simple to understand & retain the concepts.

Lets understand “5G NR SS Block”

a frame in 5G NR consists of 10 ms duration. A frame consists of 10 subframes with each having 1ms duration similar to LTE. Each subframe consists of 2μ slots. Each slot can have either 14 (normal CP) or 12 (extended CP) OFDM symbols. All the subcarrier spacing options have 14 OFDM symbols. 60 KHz spacing supports both normal and extended CP types.

The periodic transmission of SS burst (carrying SS blocks) from gNB to UE at every 20 ms interval. In 5G NR system SS blocks are transmitted using directional beams unlike LTE. In LTE, downlink frame is transmitted omnidirectionally which carries PSS and SSS signals. UE is aware of their location in control channel.

SS block contains are as follows.

  • 1 Symbol PSS
  • 1 Symbol SSS
  • 2 Symbols PBCH
  • Each SS Bursts carry one or multiple SS blocks.
  • SS Burst set consists of one or multiple SS bursts.
  • Transmission is periodic (20 ms by default).
  • The transmission of SSBs within SS burst set is confined within a 5 ms window.