NASA Deep Space Network DSN
We have all seen the pictures of the deep space antennas with large monster reflector dishes and massive supporting structures.
NASA Deep Space Network - or DSN - is an international network of antennas that supports interplanetary spacecraft missions and radio and radar astronomy observations for the exploration of the solar system and the universe. The network also supports selected Earth-orbiting missions.
Now take a look at some new types of antennas being manufactured.
JPL And NASA New Antenna Projects
Space Fed Lens Antennas
These antennas consist of a focal surface and a planar lens array. Which means that there is a membrane or membranes which are the main signal collection points. From there, the signals are focused onto another surface, where the signals are processed through a digital control unit. These units are all linked together and electronically steered together in an array to increase the signal processing capabilities and the antenna gain. See the example picture for an idea of the overall size of this space fed lens antenna versus the deep space one.Etched Antenna Pictures Courtesy of E-FAB, Inc.
Space Fed Lens Antenna
Pictured above is a space fed lens, 3 meter panel which has 4 photo chemically etched sections all integrated into one unit.The way this particular antenna system is to be used is quite high tech. See:
Linking Satellites Via Earth "Hot Spots" and the Internet to Form Ad Hoc Constellations
As more assets are placed in orbit, opportunities emerge to combine various sets of satellites in temporary constellations to perform collaborative image collections. Often, new operations concepts for a satellite or set of satellites emerge after launch. To the degree with which new space assets can be inexpensively and rapidly integrated into temporary or "ad hoc" constellations, will determine whether these new ideas will be implemented or not. On the Earth Observing 1 (EO-1) satellite, a New Millennium Program mission, a number of experiments were conducted and are being conducted to demonstrate various aspects of an architecture that, when taken as a whole, will enable progressive mission autonomy. In particular, the target architecture will use adaptive ground antenna arrays to form, as close as possible, the equivalent of wireless access points for low earth orbiting satellites. Coupled with various ground and flight software and the Internet, the architecture enables progressive mission autonomy. Thus, new collaborative sensing techniques can be implemented post-launch.
eo1.gsfc.nasa.gov/new/SensorWebs/EO-1 SPIE paper on Hotspots 2004 11-18-04
JPL KA-Band Spaceborne Antennas
This is just one of 16 etched membrane strips that will be formed into a 3.2 meter antenna. There is even experimentation with inflatable antennas using membranes. See:
Design and Development of an Inflatable Reflectarray Antenna
With the development of inflatable technologies, inflatable structures used as large space antennas are becoming very possible for near-term space missions. This article discusses the development of an inflatable/self-rigidizable structure for a 3-m 32-GHz (Ka-band) reflectarray antenna. This reflectarray antenna uses a beamscanning reflectarray antenna with circular-polarization technology. This technology uses a flat surface instead of a parabolic surface for the radio frequency component. A flat "natural" thin-membrane surface is much easier to accomplish and maintain than is a curved "non-natural" parabolic surface.
http://tmo.jpl.nasa.gov/progress_report/42-149/149D.pdf
Antenna manufacturing certainly has evolved over the years. With the new precision photo chemical machining and etching process advantages, very tight tolerance items can be fabricated.
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