High Frequency
Radar
Astronomy With HAARP
Paul Rodriguez
Naval Research Laboratory
Information Technology Division
Washington, DC 20375, USA
Edward Kennedy
Naval Research Laboratory
Information Technology Division
Washington,
DC
20375, USA
Paul Kossey
Air Fcrce Research Laboratory
Space Vehicles Directorate
Hanscom AFB, MA 01731, USA
Abstract-At
high frequency, radio waves will interact with
space plasmas and surfaces
of
local astronomical objects,
producing an echo that can provide new diagnostic data. The
availability of high power radars operating
at
high frequencies
opens a window for the remote investigation
of
our
surrounding
space environment. We discuss and illustrate this technique with
some specific examples.
I. INTRODUCTION
Over a period
of
several years, the High frequency Active
Auroral Research Program (HAARP) transmitting array near
Gakona, Alaska, has increased
in
total power
from
300
kW
to
960 kW (see Fig. I).
In
the final configuration the total power
ofHAARP will be 3.6 MW, making
it
the most advanced and
powerful high frequency (HF) radar facility used for research
purposes. The basic science objective
of
HAARP is
to
study
nonlinear effects associated with ionospheric modification by
high power radio waves. These modification experiments are
carried out
at
frequencies in the range 2.8 to
IO
MHz.
The
HAARP phased array is designed to provide agility in power,
modulation, frequency selection, and beam forming.
In recent experiments [1],[2],[3], we have begun to utilize
the HAARP array for experiments in
HF
radar astronomy,
Le.,
to study regions and objects beyond the Earth's
ionosphere. The objective
of
these investigations is
to
advance and discover new understanding
of
the physical
characteristics and interactions in regions
of
our solar system
that are accessible through high power radio wave
transmissions. These regions include the solar corona and
coronal mass ejections (CMEs), planetary hard sulfaces (e.g.,
the Moon and asteroids), and astronomical plasmas (solar
wind, magnetosphere, dusty plasmas). While our principal
research tool will be the high power phased array provided by
HAARP,
we
plan
to
have access to several other facilities
providing state-of-the-art capabilities. We believe that this
new window for radar investigations can provide new
understanding
of
solar system phenomena.
Fig.
1.
The HAARP array.
II.
DISCUSSION
In
this discussion we review several experiments that
illustrate our objectives and approach
to
HF
radar astronomy
investigations. Some
of
these experiments have been
done
in
collaboration with the NASAIWIND satellite and its
HF
radio
wave receiver (the WAVES experiment). The unique orbit
of
WIND has provided a wide range
of
radial distances from
Earth, including lunar flybys, over which we are able to study
the interactions
of
radio waves transmitted
from
HAARP.
The HAARP-WIND bistatic configuration has allowed new
techniques for conducting
HF
radar experiments beyond the
Earth's ionosphere. Other experiments
are
to
be conducted
with ground-based receiving arrays, such
as
the
Wink.
HF
array, operated by the University
of
Texas.
We
are also
planning future experiments utilizing the Low Frequency
Array (LOFAR) that will provide a large collecting area array
for radio astronomical research.
0-7803-7920-9/031$17.00 ~003 IEEE
154
2003 IEEE Radar Conference
