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1. A system for looking ahead of a drill bit, comprising: a plane wave generator (PWG) tool configured for being deployed downhole inside a wellbore for formation evaluation and generation of reflection data; a power source configured to provide electric power to the PWG tool for the formation evaluation and the generation of the reflection data; a surface control system configured to receive the reflection data from the PWG tool and generate image data of a subsurface rock formation based on the received reflection data; and a wireline that electrically couples the PWG tool to the power source and that communicatively couples the PWG tool to the surface control system; wherein the PWG tool includes a beam forming network (BFN) architecture and a plurality of antenna elements mounted to a base of the PWG tool and configured to transmit and receive electromagnetic signals, the base of the PWG tool is a cylindrical base and a space between the plurality of antenna elements on the base is filled with microwave absorbent material; the plurality of antenna elements are mounted on the cylindrical base as a circular array of a plurality of concentric rings of antenna elements, each of the plurality of concentric rings including at least one of the plurality of antenna elements, and the BFN architecture is configured to individually control relative amplitude and phase weights between the plurality of concentric rings of antenna elements, while exciting each antenna element within the same concentric ring with the same amplitude and phase.
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