Ray antenna array (RAA) was recently proposed as a novel multi-antenna architecture that arranges multiple massive cheap antenna elements into simple uniform linear arrays (sULAs) with different orientations. Compared with traditional architectures like hybrid analog/digital beamforming with uniform linear array (ULA) and uniform circular array (UCA), RAA has several promising advantages such as significantly reduced hardware cost, higher beamforming gains and the ability of providing uniform angular resolution for all directions. In this paper, we propose a full-angle RAA architecture and an innovative omnicell wireless communication paradigm enabled by full-angle RAA. The proposed full-angle RAA expands RAA's orientation angle to the full angle domain, such that the RAA's advantages can be exploited to all directions. This further enables the new concept of omnicell wireless communication system, with the base station equipped by full-angle RAA and deployed at the center of each cell. Compared to the conventional cell sectoring wireless communication system, the proposed omnicell system is expected to not only significantly reduce the inter-user interference, but also improve the cost efficiency. Extensive analytical and numerical results are provided to compare those key performance indicators such as the spatial resolution and the communication rate of the proposed full-angle RAA based omnicell wireless communication system against the conventional ULA/UCA-based cell sectoring systems.