Table 2.
Antenna tuned lengths and impedances in 0.35% saline, the cable attenuation factors used for the EM calculations, and the fraction (%) of the net resistive losses attributable to the radial E-field.
| Field | 0.5 T | 1 T | 1.5 T | 2 T | 3 T | 4 T | 4.7 T | 5 T |
|---|---|---|---|---|---|---|---|---|
| Cable length, λc∕4 (mm) | 2400 | 1200 | 800 | 600 | 400 | 300 | 255 | 240 |
| Attenuation factor, α (dB∕m) | 0.075 | 0.109 | 0.137 | 0.160 | 0.201 | 0.235 | 0.257 | 0.266 |
| Computed resonant whip length, λm∕4 (mm) | 26 | 35 | 39 | 40 | 42 | 40 | 37 | 36 |
| Measured resonant whip length, λm∕4 (mm) | ⋯ | 34 | 37 | 39 | 40 | 39 | 36 | 36 |
| Minimum resistance whip length (mm) | 150 | 110 | 85 | 65 | 43 | 38 | 34 | 29 |
| Computed resistance at resonance (Ω) | 44.2 | 37.5 | 34.8 | 33.4 | 32.3 | 30.8 | 31.1 | 31.0 |
| Measured resonant impedance, Zin (Ω) | ⋯ | 37.0 −0.2j | 34.7 −0.2j | 32.5 +0.1j | 32 +0.1j | 30.3 −0.1j | 29.6 −0.2j | 29.1 |
| Computed minimumR (Ω) | 19.9 | 25.8 | 29.4 | 31.4 | 32.3 | 31 | 29.9 | 29 |
| Rρ∕real(Zin) (%) | 11% | 12% | 14% | 15% | 16% | 18% | 19% | 19% |