What is the reference sensitivity requirement for a 5G NR base station receiver?
5G NR BS Reference Sensitivity
The reference sensitivity defines the minimum signal level the base station can reliably decode, directly determining the cell-edge coverage and the maximum supported cell radius.
- Performance verification: confirm specifications against the application requirements before finalizing the design
- Environmental factors: temperature range, humidity, and vibration affect long-term reliability and parameter drift
- Cost vs. performance: evaluate whether the application demands premium components or standard commercial grades
- Interface compatibility: verify impedance, connector type, and mechanical form factor match the system architecture
Frequently Asked Questions
How does sensitivity compare between 5G NR and LTE?
LTE (B7, 20 MHz): REFSENS ≈ -100 dBm (QPSK). 5G NR (n78, 100 MHz): REFSENS ≈ -95.8 dBm. The 5G receiver is approximately 4 dB less sensitive due to the wider bandwidth (100 MHz vs 20 MHz). 10 log(100/20) = 7 dB more noise, partially compensated by a better NF specification and coding gain. The reduced sensitivity is compensated by the massive MIMO array gain in 5G.
What is the NF specification for a 5G base station?
3GPP does not directly specify the NF; it specifies the REFSENS, from which the required NF can be calculated. For a wide-area base station: NF ≤ 5 dB (implicit from the REFSENS requirement). For a medium-range base station: NF ≤ 7 dB. For a local area base station (small cell): NF ≤ 10 dB. The actual NF is dominated by the first-stage LNA: a GaAs pHEMT LNA with NF = 1.0-1.5 dB at 3.5 GHz easily meets these requirements.
Does the sensitivity change with the number of antenna elements?
The 3GPP REFSENS is specified per antenna port (not per element). If the base station uses coherent combining of N elements per port: the effective sensitivity improves by approximately 10 log(N) dB. But the 3GPP specification does not require this gain; it is a design benefit. The vendor can use the array gain to either: extend the cell radius (better coverage), or use cheaper components (relaxed NF requirement per element).