Using X-ray diffraction analysis, scanning electron microscopy, thermogravimetry, and measurements of the dielectric properties up to the MW frequency range, the characterization of Bi sub(2)Ti sub(3)TeO sub(12), Bi sub(2)TiTeO sub(8), and Bi sub(6)Ti sub(5)TeO sub(22) compounds, which all include Te super(6+), was performed. As the processes of Te super(6+) reduction and the evaporation of TeO sub(2)-containing species contribute to the presence of secondary phases, the preparation of single-phase ceramics is rather difficult. To minimize the amount of secondary phases during the firing process, the pellets were muffled in a corresponding compound and then fired in an autoclave furnace under 10 bars of oxygen pressure. By sintering the Bi sub(2)Ti sub(3)TeO sub(12), Bi sub(2)TiTeO sub(8), and Bi sub(6)Ti sub(5)TeO sub(22) between 840 and 1010C, ceramics with e sub(r) ranging from 36 to 350, Q x f values from 220 to 12 500 GHz, and t sub(f) from +41 to +2600 ppmK were obtained.