Previous Work
Scientific Research
While most of the sicentific research on the EMVS antenna is done for
mobile communications, a few experiments on HF have also been performed. In
these experiments, various subsets and supersets of the 6-element array were
employed:
- two orthogonal dipoles [101];
- three orthogonal loops [102];
- four loops and for dipoles [103].
Ham Radio Systems
When some of the parameters of the impinging wave are known, a subset of the
6-element EVMS array may be used. Such simplified antenna systems have been
known in Ham Radio for a long time. Here are a few examples.
- In fox hunting, the radio waves arrive at a vertcal angle of zero, and
are always vertically polarized, so the only unknown is the azimuth of arrival.
In such circumstances an array consisting of a vertical loop and a whip has
been used with great success since 1940's [104].
Fig.1. An antenna for fox hunting consists of two collocated elements
- In EME reception,
the azimuth and elevation of the signal source (the Moon) are known, and
only polarization needs to be estimated. Leif SM5BSZ has used two collocated
yagis [105] to solve this problem.
Fig.2. Collocated Yagi antennas
- In direction finding on VLF,
Markus Vester DF6NM used a two-element collocated array
[106], since in this application,
just like in fox hunting, only the vertically polarized ground waves are received.
Fig.3. VLF receiving antenna array