Comparison of Several Basic Antennas
by Dick Stevens, N1RCT

The following is an attempt to show the modeled electrical parameters of several basic antennas with as much uniformity as feasible (Dipole, Vertical, X-Beam, Hex Beam, Moxon, 2&3 element yagis, 2&3 element Quads).  All these antennas have something they are good at and this type of comparison does not necessarily show the best features of each.  For example, the X-Beam can have a low F/B ratio at high gain which I like as a contester;  the hex beam construction lends itself to multi-banding; the Yagi is good for interlacing, the vertical has good radiation at low angles, some are easier to match impedance,  etc, etc. Some addition material is on beamgeom.htm

So, with every caveat you have ever heard, here are some results (and no conclusions):

 AO by K6STI Modeling of  several basic antennas
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All modeling done in "Free Space", 14.085 MHz, Resonant (reactance=0), Al 6063-T832 tubing, dBi gain units, 20 segments/half-wavelength = ~21" / segment.

AO varies the dimensions of the antenna to best achieve the tradeoff specified, which were Gain 40%, F/B 40%, and Rx=0 20%; this results in an optimization that may be different from other comparisons.

Notes:  The Dipole & Quads are #14 copper wire; Vertical radials are #14, all others use 1" tubing for all elements, ignoring sag in all cases. In real situations, very different choices in diameter and taper schedules and tubing vs wire are required.

Any booms are insulators (i.e. not in model).

The primary design criteria was reactance = 0 ohms, secondarily high gain and F/B ratio. (many other standards could be used to compare)

All these antennas can be designed with different goals in gain, F/B, bandwidth, SWR, etc.

All have different construction requirements, windage,  and weight.

Many react differently to ground in gain and resistance.

All have different abilities for multi-band designs and matching ease.

              Dipole Vert   XBeam   Hex   Moxon  2Yagi  2Quad  3Yagi  3Quad
          ====== ====== ====== ====== ====== ====== ====== ====== =======
Elements    1    1+4R      2      2      2      2      2      3      3              

Gain, dBi  2.06   1.97   6.77  6.33    6.95   6.93    7.34  8.25    9.32

F/B 180     0      0     8.01  7.00    8.62   8.44    17.16 24.80  23.21

Ro        73.0   108    14.2   9.85   11.4    5.34    115   21.9   44.5

Rx          0     0      0       0      0      0       0     0       0

SWR       1.46   2.16   3.52   5.07    4.40   9.36    2.31  2.28   1.12

Loss, dB   .06    .01    .10    .06     .06    .13     .16   .03   .35