Calculate SSB RE power from total cell transmit power, system bandwidth, and power boost.
SSB RE power (dBm)
PRBs in system bandwidth
Total active subcarriers
RE power (dBm)
SSB RE power (dBm)
SSB RE power (mW)
SSB bandwidth
SSB total power (dBm)
SSB occupies 20 PRBs (240 subcarriers × 4 OFDM symbols). The power boost allows SSB to have higher power than data REs for better cell detection range.
Frequently Asked Questions
What is the 5G NR SSB (Synchronization Signal Block)?
The Synchronization Signal Block (SSB) in 5G NR is a group of four OFDM symbols carrying the PSS (Primary Synchronization Signal), SSS (Secondary Synchronization Signal), and PBCH (Physical Broadcast Channel). It occupies 20 PRBs (240 subcarriers) in frequency and allows UEs to detect and synchronize with the cell. The SSB is periodically transmitted and is the first signal a UE detects during initial cell search.
What is SSB power boosting?
SSB power boosting means transmitting the SSB at a higher power spectral density than data REs. Because the SSB is critical for cell detection at the cell edge, boosting its power improves detection probability at long distances. A typical boost is +3 dB (twice the power of a data RE). The boost must be accounted for in link budget calculations as it affects SS-RSRP measurements made by the UE.
How does SSB bandwidth relate to the system bandwidth?
The SSB always occupies exactly 20 PRBs (240 subcarriers × 4 OFDM symbols) regardless of system bandwidth. For 15 kHz SCS this is 3.6 MHz; for 30 kHz SCS it is 7.2 MHz; for 120 kHz SCS (FR2) it is 28.8 MHz. The SSB is positioned within the system bandwidth at a GSCN-defined location. The ratio of SSB bandwidth to total system bandwidth determines how much total cell power is concentrated in the SSB.