IPB

Welcome Guest ( Log In | Register )

GAO: The DSN is actually falling apart
Guest_BruceMoomaw_*
post May 24 2006, 11:55 PM
Post #1





Guests






http://www.gao.gov/docsearch/abstract.php?rptno=GAO-06-445
Go to the top of the page
 
+Quote Post
 
Start new topic
Replies
elakdawalla
post May 26 2006, 06:46 PM
Post #2


Bloggette par Excellence
****

Group: Admin
Posts: 4363
Joined: 4-August 05
From: Pasadena, CA, USA, Earth
Member No.: 454



There was a lengthy presentation by Bob Preston from the DSN at OPAG on what the DSN wants and needs to do to improve over the coming decades, and it basically involves replacing all the gigantic, one-of-a-kind antennas with arrays of 6-, 12-, or 18-meter dishes (they are still experimenting to figure out which one will be the optimal size). Unlike the big dishes, each of which needs its own operator, whole arrays can be operated by a single person; also they can plan to have some percentage of all the dishes down at any given time for routine maintenance. Also they can just devote as many dishes as they need to a single spacecraft, splitting the array to support several spacecraft at once or using the whole array for high bandwidth. They've got to be replaced because the big dishes cannot be upgraded to support Ka-band communications.

--Emily


--------------------
My blog - @elakdawalla on Twitter - Please support unmannedspaceflight.com by donating here.
Go to the top of the page
 
+Quote Post
Guest_Richard Trigaux_*
post May 26 2006, 07:12 PM
Post #3





Guests






QUOTE (elakdawalla @ May 26 2006, 06:46 PM) *
They've got to be replaced because the big dishes cannot be upgraded to support Ka-band communications.

--Emily


Yes if the price of a large dish is proportional to more than the square of the diametre, it is better to use a collection of smaller dishes, which cost is only proportional to the square of the (simulated) diametre.


Upgrading the larger dishes to higher frequencies would require to resurface them with a greater accuracy, a thing impossible as the dish somewhat flexes with its movement or with wind, it would need to be rigidified, that means completely rebuilt. So the price of a large dish sharply increases with frequency, while not with small dishes.

Maybe the solution would come from many small dishes spread by clusters or isolated all over the world, in more or less politically stable places, by any state which would want to contribute, or even by private owners. To cut the cost, we would use mass production for the dishes, and ship them by sea.
Go to the top of the page
 
+Quote Post
Bob Shaw
post May 26 2006, 11:01 PM
Post #4


Senior Member
****

Group: Members
Posts: 2488
Joined: 17-April 05
From: Glasgow, Scotland, UK
Member No.: 239



QUOTE (Richard Trigaux @ May 26 2006, 08:12 PM) *
Maybe the solution would come from many small dishes spread by clusters or isolated all over the world, in more or less politically stable places, by any state which would want to contribute, or even by private owners. To cut the cost, we would use mass production for the dishes, and ship them by sea.


Richard:

I'm for the democratisation of data, so far as possible, and the notion of many dish arrays is very attractive.

We need to look not only to the current costs of spacecraft data reception, but also the 'distant' costs - Voyager being a prime example. Imagine if Alexander Carnegie funded the Voyager Interstellar Mission, and the new institutions which would be required (anybody want to mention SETI?). We see another analogue in AMSAT, or even SLOOH. The bottom line is that a paradigm shift has to come, whether it be commercial or non-commercial - the rate of change in the volume of data transmission across the Solar System may not follow Moore's Law exactly, but it's certainly in the same league!

Bob Shaw


--------------------
Remember: Time Flies like the wind - but Fruit Flies like bananas!
Go to the top of the page
 
+Quote Post

Posts in this topic
- BruceMoomaw   GAO: The DSN is actually falling apart   May 24 2006, 11:55 PM
- - Analyst   No Reply yet, although without the DSN no planetar...   May 26 2006, 09:14 AM
|- - Richard Trigaux   Things will not spontaneously become better. DSN ...   May 26 2006, 10:44 AM
|- - Jim from NSF.com   QUOTE (Richard Trigaux @ May 26 2006, 06...   May 26 2006, 11:44 AM
||- - Richard Trigaux   QUOTE (Jim from NSF.com @ May 26 2006, 11...   May 26 2006, 02:28 PM
||- - djellison   QUOTE (Jim from NSF.com @ May 26 2006, 12...   May 26 2006, 03:28 PM
||- - Jim from NSF.com   QUOTE (djellison @ May 26 2006, 11:28 AM)...   May 26 2006, 07:01 PM
|- - Chmee   QUOTE (Richard Trigaux @ May 26 2006, 06...   May 26 2006, 07:42 PM
- - Analyst   (Upfront and/or operating) costs? Size (70m) and p...   May 26 2006, 12:21 PM
|- - Richard Trigaux   QUOTE (Analyst @ May 26 2006, 12:21 PM) A...   May 26 2006, 02:45 PM
- - RNeuhaus   What would be the solution? More 70 meters antenna...   May 26 2006, 04:03 PM
- - Richard Trigaux   A suggest RNeuhaus, there exist new antenna techno...   May 26 2006, 05:46 PM
- - djellison   Were there any problems w.r.t. politicis, one coul...   May 26 2006, 06:22 PM
- - elakdawalla   There was a lengthy presentation by Bob Preston fr...   May 26 2006, 06:46 PM
|- - Richard Trigaux   QUOTE (elakdawalla @ May 26 2006, 06:46 P...   May 26 2006, 07:12 PM
||- - Bob Shaw   QUOTE (Richard Trigaux @ May 26 2006, 08...   May 26 2006, 11:01 PM
|- - RNeuhaus   QUOTE (elakdawalla @ May 26 2006, 01:46 P...   May 26 2006, 07:29 PM
- - djellison   There is already international involvement to some...   May 26 2006, 07:44 PM
|- - AlexBlackwell   QUOTE (djellison @ May 26 2006, 07:44 PM)...   May 26 2006, 07:48 PM
||- - Bob Shaw   QUOTE (AlexBlackwell @ May 26 2006, 08:48...   May 26 2006, 10:48 PM
|- - Richard Trigaux   QUOTE (djellison @ May 26 2006, 07:44 PM)...   May 26 2006, 08:23 PM
|- - AlexBlackwell   QUOTE (Richard Trigaux @ May 26 2006, 08...   May 26 2006, 08:28 PM
- - djellison   Truth be told, I could go even further and say tha...   May 26 2006, 08:14 PM
|- - Richard Trigaux   QUOTE (djellison @ May 26 2006, 08:14 PM)...   May 26 2006, 08:36 PM
|- - DonPMitchell   QUOTE (Richard Trigaux @ May 26 2006, 01...   May 27 2006, 02:21 AM
|- - Richard Trigaux   Thanks DonPMitchell to bring more exact info than ...   May 27 2006, 07:30 AM
|- - djellison   QUOTE (Richard Trigaux @ May 27 2006, 08...   May 27 2006, 07:39 AM
|- - garybeau   Regardless of how much money is spent upgrading th...   May 27 2006, 01:26 PM
- - djellison   ESA is slowly getting there with a DSN of it's...   May 27 2006, 07:05 AM
- - DonPMitchell   Space programs have a long history of "Not In...   May 27 2006, 03:57 PM
|- - helvick   QUOTE (DonPMitchell @ May 27 2006, 04:57 ...   May 27 2006, 05:04 PM
||- - Richard Trigaux   QUOTE (helvick @ May 27 2006, 05:04 PM) N...   May 29 2006, 01:14 PM
|- - Richard Trigaux   QUOTE (DonPMitchell @ May 27 2006, 03:57 ...   May 29 2006, 12:58 PM
- - DonPMitchell   I agree, Kourou is strategically important, it wou...   May 27 2006, 05:31 PM


Reply to this topicStart new topic

 



RSS Lo-Fi Version Time is now: 25th July 2014 - 08:14 AM
RULES AND GUIDELINES
Please read the Forum Rules and Guidelines before posting.

IMAGE COPYRIGHT
Images posted on UnmannedSpaceflight.com may be copyrighted. Do not reproduce without permission. Read here for further information on space images and copyright.

OPINIONS AND MODERATION
Opinions expressed on UnmannedSpaceflight.com are those of the individual posters and do not necessarily reflect the opinions of UnmannedSpaceflight.com or The Planetary Society. The all-volunteer UnmannedSpaceflight.com moderation team is wholly independent of The Planetary Society. The Planetary Society has no influence over decisions made by the UnmannedSpaceflight.com moderators.
SUPPORT THE FORUM
Unmannedspaceflight.com is a project of the Planetary Society and is funded by donations from visitors and members. Help keep this forum up and running by contributing here.