| AR |
Axial Ratio — ratio of semi-major to semi-minor axis of the polarization ellipse, expressed in dB. 0 dB = perfect circular; ∞ dB = perfect linear. |
| CST |
Computer Simulation Technology — vendor for EM simulation; their .ffs Farfield Source format is supported as an RFlect export target. |
| Directivity |
Peak gain divided by spherical-average gain. The "shape" of the pattern, independent of efficiency. |
| ECC |
Envelope Correlation Coefficient — how correlated two antenna patterns are; matters for MIMO diversity. |
| Efficiency (η) |
Radiated power / accepted power. Includes ohmic and mismatch losses. |
| F/B |
Front-to-Back ratio. Gain at the peak direction minus gain at 180° from the peak. |
| Fernet |
Symmetric AES-128 + HMAC-SHA256 encryption scheme used to encrypt API keys at rest. |
| Gain |
Power radiated in a given direction per unit solid angle, relative to isotropic. Gain = Efficiency × Directivity. dBi units. |
| HPBW |
Half-Power Beamwidth, aka -3 dB beamwidth. Angular width where gain drops to half-peak. |
| HPOL / VPOL |
H- and V-polarization. Ludwig-3: HPOL → $E_\phi$, VPOL → $E_\theta$. |
| Kraus |
Approximation for efficiency: $\eta \approx 32400 / (\text{HPBW}_E \cdot \text{HPBW}_H)$. Only valid for moderately directional antennas. |
| LHCP / RHCP |
Left-/Right-Hand Circular Polarization. IEEE convention: looking in direction of propagation. |
| MCP |
Model Context Protocol — open spec for AI assistants to call tools on external servers. |
| MEG |
Mean Effective Gain — mean of the antenna gain weighted by the angular power spectrum of the environment. |
| PBKDF2 |
Password-Based Key Derivation Function. RFlect uses PBKDF2-HMAC-SHA256 with 600 K iterations to derive the Fernet key. |
| SFF |
System Fidelity Factor — normalized cross-correlation between transmitted and received UWB pulses. 1.0 = perfect; 0.95+ usually good. |
| setup_group |
A free-text tag on a cal-drift run identifying its methodology epoch (e.g. pre-2024-cable-change). Mismatch is flagged when comparing across groups. |
| TRP |
Total Radiated Power. Integral of radiated power over the sphere. IEEE solid-angle formula with $\sin\theta$ Jacobian. |
| Touchstone |
Industry-standard .s2p / .s1p file format for S-parameters. RFlect's UWB pipeline reads .s2p. |
| VSWR |
Voltage Standing Wave Ratio. Derived from S11 magnitude. 1.0 = perfect match; 2.0 ≈ -9.5 dB return loss. |
| WTL |
Wireless Telecom Lab — the chamber-output format RFlect's parsers were built against (V5.02 / V5.03). |
| XPD |
Cross-Polarization Discrimination — co-pol field divided by cross-pol field, in dB. Uses 20 log, not 10 log. |