Mode 5G NR cells

5G NR cells: the public broadcast of NR cells (PSS / SSS / PBCH, MIB).

Group	Cellular & rail
Default frequency	3541.44 MHz
Default sample rate	20 Msps
In the mode list	5G NR, GSCN scan

Step-by-step: Tutorial-5G-NR-cells

What 5G NR cells is

5G NR cells broadcast synchronisation and master information blocks (SS/PBCH) that identify the cell. OnAir reads that public broadcast only.

Frequencies and settings

NR SS/PBCH blocks on the sync raster (GSCN) of n1, n3, n7, n8, n20, n28, n38, n40, n41, n77 and n78, 15 / 30 kHz SSBs, from 3.84 / 7.68 Msps (20 Msps searches several raster points per step).

Setting	Value
Start frequency	3541.44 MHz
Tuning range of the mode table	600 to 4200 MHz
Sample rate asked	20 Msps
Lowest working rate	3.84 Msps
Channel width	20 MHz

OnAir takes any frequency you type; the numbers above are the mode's starting point and the range its table describes. In the app the shortcut label is 5G NR, GSCN scan.

What OnAir shows

PCI (PSS / SSS), SSB index and the beams heard, SS-RSRP / RSRQ / SINR, carrier offset, and the MIB from the polar-coded PBCH: SFN, common subcarrier spacing, k_SSB, DMRS type A position, CORESET#0 and search space 0 of SIB1, barred, intra-frequency reselection. Receive only, public broadcast; SIB1 (operator, TAC, cell id) is not decoded yet, so the tower map stays empty.

The mode's own tab has these screens: Cells, Beams, Map, Log. The other tabs (Overview, Receiver, Scan, History) are described on the Main window page.

Tips and caveats

• Checked with generated signals and impairments; recordings of real signals welcome.
• Which radio: No: this mode needs a radio that samples at 3.84 Msps or more, and an RTL-SDR reaches about 2.4 Msps.
• Try it without a radio: most modes include a built-in synthetic test signal, so you can open the screen and try the controls first.
• Receiving and the law: OnAir only reads the public broadcast information of cells and base stations, and does not decrypt or follow any user traffic. Check the rules where you live. See Legal.

Related pages

• All modes, Cellular & rail
• Supported radios, Troubleshooting, FAQ
• More in Cellular & rail: Cell towers, NB-IoT cells, GSM-R, LBJ