A structural grid is provided with continuous and discontinuous beam members coupled by splices, a front structure coupled to the structural grid, the front structure including a walkway and cables, a radome coupled to the front structure. The structural grid is coupled to a plurality of antenna subassemblies. The antenna subassemblies have a forward housing including an RF manifold coupled to a circulator, an aft housing coupled to the forward housing, containing a line replaceable unit that is serviceable or maintainable through the aft housing.