|
Size: 713
Comment:
|
Size: 896
Comment:
|
| Deletions are marked like this. | Additions are marked like this. |
| Line 18: | Line 18: |
| We can scale D and k, and also modify amplitudes across the array like a Hamming window, and see how that changes the sidelobes. | We can scale D and k, and also modify amplitudes across the array like a Hamming window, and see how that changes the sidelobes. This happens on top of the array of perhaps hundreds of emitters on the thinsat itself, which beamforms to a few degrees of angle, reducing power splattered far from the target. |
Array Phasing
When we randomly dither the position of the emitters in a 3 dimensional phased array, it smears out the grating lobes. I am looking for a better function.
A smear function to try:
D = \lambda/2 k = 2 \pi / N * L
\Delta x = D * ( \sin( k z ) + \cos( k y ) )
\Delta y = D * ( \sin( k x ) + \cos( k z ) )
\Delta z = D * ( \sin( k y ) + \cos( k x ) )
... or some variation of that. This assumes the spacing L >> \lambda , a sparse array, so that the antennas do not couple (much). We can scale D and k, and also modify amplitudes across the array like a Hamming window, and see how that changes the sidelobes.
This happens on top of the array of perhaps hundreds of emitters on the thinsat itself, which beamforms to a few degrees of angle, reducing power splattered far from the target.
MORE LATER