NLO Crossed-wire antenna. Simulations for 500KHz (600m)
|Simple dipole feed:
N and S wires driven.
E and W wires unconnected.
Model: x45_dipole_600m.ez .
|Polarisation is horizontal from broadside direction and vertical from end-on.
Radiation pattern is typical for a low electrically short horizontal wire.
Eficiency is low but acceptable.
|Splayed dipole feed:
Field strength pattern is practically identical to simple dipole but rotated through 45°.
Model: x45_splay_600m .
Zin = 3 - j700 Ω at 500KHz
Max gain: -13dBi.
N+W driven against S+E gives vertical polarisation in NW - SE Direction (end on) and horizontal polarisation in SW-NE direction (broadside).
Strapping the antenna to make two long wires which cross at the centre, and driving the two wires in opposition, produces a null in the vertical direction.
Model: x45_2T_600m.ez .
Zin = 2.4 - j730 Ω at 500KHz
The disadvantage of this configuration for 500KHz working is extremely low efficiency (max gain: -37.4dBi).
Polarisation is vertical in N-S and E-W directions (looking end-on to either wire), and Horizontal in NE-SW and NW-SE directions.