At approximately 290 K, matched thermal noise density is about −174 dBm/Hz. Integrated noise increases with measurement bandwidth.
How it works in practice
For an ideal rectangular-equivalent bandwidth B, noise power is approximately −174 + 10 log10(B in Hz) dBm before receiver noise figure. Actual filters use equivalent noise bandwidth, and receiver behavior adds its own contributions. This is a model, not a measured sensitivity result.
Example and interpretation
At 1 MHz bandwidth, thermal noise is approximately −114 dBm before receiver noise figure.
Checks before use
- Use equivalent noise bandwidth
- Calculate integrated noise
- Include receiver noise figure
- Compare with the required signal criterion
Important limit
Noise power alone does not define sensitivity for every modulation or detection method.
Related Centron RF product
SMA 2 W 6 GHz fixed attenuator. Use calculated levels to define a requirement, then compare it with the exact product’s current bandwidth, input power, impedance and available attenuation options. Calculations assume stated conditions and do not replace a component datasheet.
Further reading
Keysight: Fundamentals of RF and Microwave Power Measurements. This background reference explains general principles; the selected Centron RF model’s datasheet governs its own ratings.
Related guides
Educational guide. Numerical examples use the stated assumptions and are not test results for a supplied unit.