What is CE (Coverage Enhancement) Levels in NB-IOT cell?

What is CE (Coverage Enhancement) Levels in NB-IOT cell?

And how it could be helpful UE to attach NB-IOT cell procedure from remote area locations?

Deep Indoor coverage is an important aspect of NB-IoT, which is essential for IoT application requiring devices to be positioned in areas not readily accessible by 2G, 3G, or LTE coverage, such as in the basements of buildings, parking garages, etc. This is achieved by repeating Layer 3 (RRC, NAS) messages a predefined number of times, thereby increasing the probability of receivers to correctly receive and demodulate the message.

The NB-IoT standard supports three so-called Coverage Enhancement (CE)-Levels. main feature of NB-IoT is coverage extension (CE), which supports a base level (CE level 0) and two coverage extension levels (CE 1 levels and CE 2). CE levels are chosen by the network based on signal conditions (RSRP1 and CINR2).

Each CE Level determines the number of times downlink and uplink messages can be repeated to reach devices in poor coverage and the number of repetitions in each CE-Level is predefined by the network.

The CE feature essentially increases the maximum coupling loss from 144dB to up to 164dB:

  • +0dB vs. GSM signal with CE Level 0 (used when coverage is good_8 repetitions)
  • up to +10dB with CE Level 1 (with moderate 64 repetitions)
  • up to +20dB with CE Level 2 (with up to 128/512 repetitions)

Note that a higher power density (of 23 dBm) is also used in CE-Level 1 and CE-Level 2 instead of power control.

All DT’s NB-IoT networks support all three Coverage Enhancement Levels 0, 1 and 2.

While you configuring CE levels you should need to be aware about below IE protocol parameters.

  1. NPRACH repetitions:
  2. NPDCCH Repetitions:
  3. NPUSCH Repetitions:
  4. NPDSCH Repetitions :
  5. rach-InfoList-r13
  6. nprach-config-r13 (In this IE will give information about rsrp-Thresholdsprachinfolist-r13
  7. nprach-parametersList-r13(if you configured CE0,you can only able to see one parameter nprach list info in protocol logs,if CE1(can see two parameters configured list infor for CE0&CE1)and for CE2 three parameters list.

What is CE (Coverage Enhancement) Levels in NB-IOT cell

Source: Puliraju Mulinti on LinkedIn: #all #nb #technology #iot