Robot Antenna Problem

I am working on a project for school in which my group must design a robot that can remotely locate a beacon emitting a 433 Mhz signal. We are using array of two dipoles and phase monopulse comparison to make multiple angle bearings of the beacon, to which we will later apply some processing to provide a location of the beacon. Our robot will travel a straight path and we will know which side of the path the beacon is on.
We are using a mesh screen behind the antennas to direct their radiation path toward the beacon. We were wondering whether we should position both the screens parallel to the path we are traveling, or have the screens facing 45 degrees outward in order to get more directionality on the signal?
Here are some images of the two proposed designs. The black circles are the antennas, and the green lines are the mesh screens. Both images are top view:
The first design: http://i.imgur.com/79r4T.png
The second design: http://i.imgur.com/2oH5H.png
Thanks in advance for any help. Advice is greatly appreciated.
- Billy Maier

On Thu, 01 Mar 2012 01:45:07 -0600, snipped-for-privacy@nmt.edu (Billy Maier) wrote:
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The second 45° thing does not make sense to me. You increase the capture range but decrease directivity. Will the antennas rotate?
w.

On 2/29/2012 11:45 PM, Billy Maier wrote:
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Are you aware that almost all the home weather stations with remote reading operate on 433 MHz?
PAul, KD7HB

On Thu, 01 Mar 2012 01:45:07 -0600, snipped-for-privacy@nmt.edu (Billy Maier) wrote:
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Not sure why you chose this method. You could do better with a directional beam antenna. At that frequency expect a lot of interference and reflections.
Tom