Long-wavelength radio astronomy observations of high resolution are of considerable scientific interest but are limited from Earth-based telescopes due to the opacity of the ionosphere. For ratio telescopes orbiting above the ionosophere, the viewing window is restricted to about 1 to 5 MHz. To obtain the maximum resolution allowable by interplanetary plasma scintillations in this range requires antenna diameters on the order of tens of kilometers. A concept for obtaining high-resolution, low-frequency observations of time-stationary discrete sources and the background continuum distribution is presented which circumvents the need for physically large antennas by using two small satellites in an interferometric mode. Antennas on each satellite measure relative phase and amplitude of the radio sources, and the combination of satellite relative motion together with ground data processing is used to synthesize an antenna aperture. Complete sky coverage is obtained by computer phasing of the elements of the aperture plus orbital precession of the aperture plane. An example system that utilizes this concept is presented.
[1]
E. Jacobs.
On the spatial frequency response of an antenna
,
1966
.
[2]
G. Huguenin,et al.
IONOSPHERIC FOCUSING IN THE PRESENCE OF THE EARTH'S MAGNETIC FIELD
,
1964
.
[3]
A. E. Lilley,et al.
Measurements of radio noise at 0.700 mc and 2.200 mc from a high-altitude rocket probe
,
1964
.
[4]
C. Haselgrove,et al.
Ray paths from a cosmic radio source to a satellite in orbit
,
1961,
Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences.
[5]
A. Hewish,et al.
The synthesis of large radio telescopes by the use of radio interferometers
,
1959
.
[6]
A. Molozzi,et al.
Cosmic Noise Measurements from 1960 η1 at 3.8 Mc./s.
,
1961,
Nature.
[7]
G. Ellis.
Use of Z-Mode Propagation for observing Cosmic Radio Noise from Earth Satellites
,
1962,
Nature.