linkbudget

RF link budget analysis for satellite and terrestrial communication systems.

Features

Example

use linkbudget::{LinkBudget, PathLoss, Transmitter, Receiver};

let budget = LinkBudget {
    name: "Ka-band LEO downlink",
    bandwidth: 250.0e6,
    transmitter: Transmitter {
        output_power: 10.0,  // dBm
        gain: 35.0,          // dBi
        bandwidth: 250.0e6,  // Hz
    },
    receiver: Receiver {
        gain: 40.0,           // dBi
        temperature: 290.0,   // K
        noise_figure: 2.0,    // dB
        bandwidth: 250.0e6,   // Hz
    },
    path_loss: PathLoss {
        frequency: 20.0e9,   // 20 GHz
        distance: 550.0e3,   // 550 km LEO
    },
    frequency_dependent_loss: Some(3.0), // rain fade
};

println!("EIRP: {:.1} dBm", budget.transmitter.eirp_dbm());
println!("G/T: {:.1} dB/K", budget.receiver.g_over_t_db());
println!("Path Loss: {:.1} dB", budget.path_loss());
println!("SNR: {:.1} dB", budget.snr());
println!("PHY Rate: {:.1} Mbps", budget.phy_rate().mbps());

Doppler

use linkbudget::doppler;

let freq = 14.0e9; // 14 GHz Ku-band
let radial_velocity = 7000.0; // m/s (LEO satellite)

let shift = doppler::doppler_shift_hz(freq, radial_velocity);
println!("Doppler shift: {:.0} Hz", shift); // ~327 kHz

Power Flux Density

use linkbudget::pfd;

let eirp_dbw = 45.0;
let distance = 550.0e3; // 550 km

let pfd = pfd::power_flux_density_dbw_per_m2(eirp_dbw, distance);
println!("PFD: {:.1} dBW/m²", pfd);

Quantization

use linkbudget::quantization;

let snr = quantization::quantization_snr_db(12); // 12-bit ADC
println!("Quantization SNR: {:.2} dB", snr); // 74.00 dB

let enob = quantization::enob_from_snr(65.0);
println!("ENOB: {:.1} bits", enob); // 10.5 bits

CLI

linkbudget          # runs the built-in example

Articles and Papers

• Path Loss, Antenna Gain, and Frequency Dependence