A new LGS configuration termed Projected Pupil Plane Pattern (P 4), together with the corresponding wavefront sensing and reconstruction method, is presented. A theoretical analysis and Monto Carlo simulation show the feasibility of this novel method for a 4m-class telescope and great promise for the next generation of ELTs. Also we carry out a simple laboratory test with only defocus aberration and compare the reconstructed phase with the corresponding result from a Shack-Hartmann WFS. A further high-order experiment will follow, as well as plans for an on-sky test at William Herschel Telescope (WHT), La Palma.