How to generate n points and restrict the distance between them to be greater than a given value in MATLAB?

I would like to generate, randomly with uniform distribution, n points such that the distance between any point is greater than some fixed value.

Here is the scenario that I have in MATLAB:

• I have M red points which I generate randomly with uniform distribution as follow: the x-abscissa of the M red points are xr = rand(1, M) and the y-ordinate of the M red points are yr = rand(1, M).
• Also, I have M black points which I generate similarly as the red points, i.e., xb = rand(1, M) and yb = rand(1, M).

• Then, I calculate the distances between all the points as follow:

  x = [xr, xb];
  y = [yr, yb];
  D = sqrt(bsxfun(@minus, x, x').^2 + bsxfun(@minus, y, y').^2);
  d = D(1:M, M + 1:end);
  
  

• Now, I have to restrict the distance d to be always greater than some given value, say d0=0.5.

How to do this?