Wireless Link Budget & FSPL Calculator
Calculate FSPL, RSSI, link margin, and EIRP for outdoor fixed wireless links (2.4GHz, 5GHz, 11GHz, 60GHz, 80GHz).
Calculating Fixed Wireless Link Budgets & Signal Strength
A wireless link budget calculates the received signal indicator (RSSI) by adding transmitter power and antenna gains, then subtracting free space path loss (FSPL) and cable losses across a given distance and frequency.
Designing microwave backhaul and WISP subscriber connections with a minimum 15–20 dB fade margin prevents link drops during heavy rain, thermal fading, or atmospheric interference.
Interactive Wireless Link Budget & FSPL Calculator Workspace
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Link Budget Calculator
Calculate FSPL, RSSI, and EIRP for wireless links (2.4GHz to 60GHz).
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Link Budget Calculator
Input Parameters:
Calculated Link Results:
Real-World Calculation Walkthrough
5.8 GHz point-to-point wireless backhaul link over 5.0 kilometers
Input Parameters
Calculation Output
Wireless Link Budget & FSPL Calculator Engineering FAQs
What is Free Space Path Loss (FSPL) and how is it calculated?
FSPL represents signal attenuation over open space without obstacles. It increases logarithmically with distance and frequency: FSPL(dB) = 20log10(d) + 20log10(f) + 32.44.
What is a recommended fade margin for PTP and PTMP links?
Maintain a minimum 15 dB fade margin for 5 GHz links and 20–25 dB for 11 GHz or 60/80 GHz millimeter wave links susceptible to rain fade.
How does antenna gain affect link distance?
Doubling antenna gain (+6 dBi total) doubles the theoretical line-of-sight distance for the same target RSSI.
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