Abstract: The inventor discloses a bidirectional communication system for electric power load management and distribution automation application, and the like, wherein outgoing control signals to a plurality of remotely located receivers and transmitters are sent using an existing standard AM broadcast station using small angle subaudible quadrature modulation. The broadcast signal is detected by narrowband synchronous receivers phase-locked to the carrier component of the broadcast station. The radio frequencies of the plurality of reverse link transmitters are closely spaced and synthesized from frequency of said broadcast carrier and their time of transmission, digital bit streams, and message frames are all synchronized from the broadcast signal. The broadcast station thereby orchestrates all communication activity to and from the plurality of remote locations to optimize traffic flow and maximize a priori information to all components to significantly increase reliability.

Abstract: The inventor discloses an ultra narrow band relatively ultra stable radio apparatus for communicting paging or control signals from a central transmitter to a multiplicity of remotely located receivers, which receivers may be carried on the person of individuals or may be fixed to other devices which they control, such as city traffic control lights, programmable signs, machines, or the like, wherein the central transmitting device and the remote receiving device are both phase locked to a local broadcast station RF carrier so as to provide a means to precisely synchronize the transmitting device with the receiving device and thereby achieve very high signal-to-noise ratio transmissions. The apparatus is capable of transmitting a digital identification code or a digital message and the receiving devices may output a simple on-off signal indicating the presence of a call, or digital message may be output to control an apparatus attached to said receiver.