= Solution
Use a <two-element radio interferometer>: couple two small dishes coherently and align the projected baseline along the angular separation of the neighbouring satellites. Each dish's broad <antenna> response should include both satellites. Match the electronic delays so that the desired satellite arrives in phase at the combiner. For baseline <length> $b$ perpendicular to the central line of sight, a small angular displacement $\theta$ produces geometric path difference $b\sin\theta$ and <phase difference>
$$
\phi(\theta)=\frac{2\pi b}{\lambda}\sin\theta.
$$
For equal signal <amplitudes> from one source, the output <wave intensity> is $4I_0\cos^2(\phi/2)$. Put one satellite on a maximum and its neighbour on the first null: $\phi(\theta_R)=\pi$. The smallest useful projected baseline is therefore
$$
\boxed{b=\frac{\lambda}{2\sin\theta_R}\simeq\frac{\lambda}{2\theta_R}
=0.348\,\mathrm m.}
$$
The <angles> here are measured near the normal to the baseline. At a general pointing angle $\theta_0$, replace $b$ in the small-separation estimate by $b\cos\theta_0$. Longer odd-half-fringe baselines can also null the neighbour but create more angular ambiguity. This arrangement provides discrimination along one direction; two collectors alone have repeated <interference fringes> and do not produce an unambiguous full image.
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