47 CFR 95.1013 - Antennas.
(a) The maximum allowable ERP for a station in the LPRS other than an AMTS station is 100 mW. The maximum allowable ERP for an AMTS station in the LPRS is 1 W, so long as emissions are attenuated, in accordance with § 80.211 of this chapter, at the band edges.
(b) AMTS stations must employ directional antennas.
(c) Antennas used with LPRS units must comply with the following:
(1) For LPRS units operating entirely within an enclosed structure, e.g., a building, there is no limit on antenna height;
(2) For LPRS units not operating entirely within an enclosed structure, the tip of the antenna shall not exceed 30.5 meters (100 feet) above ground. In cases where harmful interference occurs the FCC may require that the antenna height be reduced; and