Calculated receiver sensitivity
Results appear above the form after submission. Values below update using your current inputs.
| Metric | Value |
|---|---|
| Bandwidth | 25.000 kHz |
| Noise figure | 5.000 dB |
| Required SNR | 12.000 dB |
| Total added losses | 7.000 dB |
| Thermal noise density | -173.975 dBm/Hz |
| Thermal noise over bandwidth | -129.996 dBm |
| Receiver sensitivity | -105.996 dBm |
| Receiver sensitivity at 50.000 Ω | 1.121 µV RMS |
Calculator inputs
Formula used
This method starts with thermal noise power, then adds receiver degradation and required detection margins. The final value estimates the minimum input signal that can still satisfy the chosen demodulation target.
How to use this calculator
- Enter the receiver noise figure in decibels.
- Provide signal bandwidth and choose the correct unit.
- Set the required SNR for your modulation target.
- Add implementation, fade, and extra hardware losses.
- Adjust temperature and impedance when needed.
- Press calculate to show sensitivity above the form.
- Review the graph to see bandwidth impact quickly.
- Export the result table as CSV or PDF.
Example data table
Sample engineering scenarios generated with the same equations used in the calculator.
| Scenario | NF (dB) | Bandwidth | SNR (dB) | Total Loss (dB) | Sensitivity (dBm) | Sensitivity (µV) |
|---|---|---|---|---|---|---|
| Narrowband voice receiver | 5.00 | 12.5 kHz | 12.00 | 7.00 | -109.01 | 0.79 |
| Telemetry receiver | 3.00 | 25 kHz | 10.00 | 3.50 | -113.50 | 0.47 |
| Wideband IF stage | 6.50 | 200 kHz | 14.00 | 7.00 | -93.32 | 4.83 |
| Low rate sensor link | 2.50 | 5 kHz | 8.00 | 2.50 | -123.99 | 0.14 |
Engineering notes
This calculator is useful during link budgeting, receiver selection, IF planning, and quick feasibility checks. Lower noise figure improves sensitivity directly. Narrower bandwidth lowers thermal noise. Required SNR and operating margins should come from the actual modulation, coding, and deployment environment.
FAQs
1. What does receiver sensitivity mean?
Receiver sensitivity is the weakest input signal a receiver can detect while still meeting a required performance target. That target is usually expressed as SNR, BER, SINAD, or another demodulation quality measure.
2. How does noise figure affect sensitivity?
Every decibel of added noise figure raises the minimum detectable signal by roughly one decibel. A lower noise figure means less internal receiver degradation and therefore better sensitivity.
3. Why does bandwidth change sensitivity?
Thermal noise increases with bandwidth. When bandwidth grows, the receiver collects more noise power, so the required signal level also increases. Narrow filters usually improve sensitivity.
4. Should I include fade margin here?
Yes, when you want a practical field target instead of an ideal laboratory threshold. Fade margin makes the required input level more conservative and better aligned with real deployment uncertainty.
5. What is the purpose of implementation loss?
Implementation loss captures real-world penalties such as imperfect filters, quantization limits, detector inefficiency, synchronization overhead, and nonideal processing. It helps bridge theory and actual hardware behavior.
6. Why is temperature included?
Thermal noise depends on absolute temperature. The common reference is 290 K, but hotter environments increase noise density slightly. Temperature adjustment is helpful for tighter engineering estimates.
7. What does the microvolt result represent?
The microvolt value converts the calculated power threshold into RMS voltage for the chosen system impedance. It is helpful when comparing against datasheets that specify sensitivity in volts.
8. Can I use this for any radio system?
It works well for many RF and communication estimates, but always verify the required SNR or quality target from the actual receiver specification, modulation, coding, and test method.