Appendix D
Quick Reference Tables
The numbers you reach for on the bench: resolution bandwidth versus FFT length, probability of intercept, window selection, signal bandwidths, and frequency bands.
Resolution Bandwidth vs FFT Length
For sample rate $f_s$ in MS/s and FFT length $N$:
| $f_s$ \ $N$ | 1024 | 4096 | 16,384 | 65,536 | 262,144 | 1,048,576 |
|---|
| 100 MS/s | 97.7 kHz | 24.4 kHz | 6.1 kHz | 1.5 kHz | 381 Hz | 95 Hz |
| 245 MS/s | 239 kHz | 60 kHz | 15 kHz | 3.7 kHz | 935 Hz | 234 Hz |
| 500 MS/s | 488 kHz | 122 kHz | 30.5 kHz | 7.6 kHz | 1.9 kHz | 477 Hz |
| 1 GS/s | 977 kHz | 244 kHz | 61 kHz | 15 kHz | 3.8 kHz | 953 Hz |
| 2 GS/s | 1.95 MHz | 488 kHz | 122 kHz | 31 kHz | 7.6 kHz | 1.9 kHz |
POI vs Burst Duration
For a swept analyzer with given sweep time and 1 GHz span at 10 kHz RBW:
| Burst \ Sweep Time | 100 us | 1 ms | 10 ms | 100 ms | 1 s |
|---|
| 10 ns | 0.0001 | 1e-5 | 1e-6 | 1e-7 | 1e-8 |
| 100 ns | 0.001 | 1e-4 | 1e-5 | 1e-6 | 1e-7 |
| 1 us | 0.01 | 0.001 | 1e-4 | 1e-5 | 1e-6 |
| 10 us | 0.1 | 0.01 | 0.001 | 1e-4 | 1e-5 |
| 100 us | 1.0 | 0.1 | 0.01 | 0.001 | 1e-4 |
For an RTSA with 10 ns POI: any burst longer than 10 ns has POI approximately equal to 1.
Window Function Tradeoff Quick-Pick
| Use Case | Window |
|---|
| General spectrum monitoring | Hann |
| Accurate amplitude measurement | Flat-top |
| Weak signal near strong (high dynamic range) | Blackman-Harris |
| Tunable extreme suppression | Kaiser |
| Tones aligned to bins (rare) | Rectangular |
| Low-noise tone detection | Hamming |
Common Signal Bandwidths
| Signal | Bandwidth |
|---|
| FM broadcast | 200 kHz |
| GSM | 200 kHz |
| ATC voice (AM) | 6 kHz |
| Wi-Fi 4 (b/g/n) | 20-40 MHz |
| Wi-Fi 5 (ac) | 20-160 MHz |
| Wi-Fi 6 (ax) | 20-160 MHz |
| Wi-Fi 6E (6 GHz) | 20-160 MHz |
| Wi-Fi 7 (be) | 20-320 MHz |
| LTE (single carrier) | 1.4-20 MHz |
| 5G NR FR1 | 5-100 MHz |
| 5G NR FR2 | 50-400 MHz |
| Bluetooth Classic | 1 MHz hops |
| BLE | 1-2 MHz hops |
| LoRa | 125-500 kHz |
| Air radar (typical) | 1-10 MHz |
| Weather radar | 0.5-5 MHz |
| GPS L1 C/A | 2 MHz |
Common Frequency Bands
| Band | Range | Band | Range |
|---|
| HF | 3-30 MHz | X-band | 8-12 GHz |
| VHF | 30-300 MHz | Ku-band | 12-18 GHz |
| UHF | 300 MHz - 3 GHz | K-band | 18-27 GHz |
| L-band | 1-2 GHz | Ka-band | 27-40 GHz |
| S-band | 2-4 GHz | V-band | 40-75 GHz |
| C-band | 4-8 GHz | W-band | 75-110 GHz |
| ISM 2.4 GHz | 2.4-2.4835 GHz | GPS L1 | 1.575 GHz |
| ISM 5 GHz | 5.725-5.875 GHz | GPS L2 | 1.227 GHz |
| GPS L5 | 1.176 GHz | | |