Abstract: A first transmitting device is used to transmit a first signal on a first carrier frequency to a relay device. The relay device receives the signal by demodulating the first carrier frequency. Subsequently, the relay device retransmits the signal by modulating a second and/or a third carrier frequency. The signal is then recovered at one or more receiving devices by demodulating the second and/or third carrier frequencies. Further, a second transmitting device transmits a second signal on a fourth carrier frequency and the relay device retransmits the signal by modulating a fifth and/or a sixth carrier frequency. The signal is then recovered at one or more receiving devices by demodulating the fifth and/or sixth carrier frequencies. The transmitting and/or receiving devices are preferably voice terminals, such as a wireless telephones or data terminals, such as portable computers.

Abstract: A method and apparatus for determining and tracking the geodetic position of a mobile platform (i.e., aircraft). The apparatus comprises a ground controller assigned to a geographic space (i.e., an airspace) and at least one mobile platform (i.e., aircraft) communicating with the ground controller on a bi-directional communications link, wherein each mobile platform (i.e., aircraft) transmits a mobile platform (i.e., an aircraft) signal comprising at least a time of transmission of the mobile platform (i.e., aircraft) signal; the ground controller transmits a ground signal comprising at least a time of transmission of the ground signal and a location of the ground controller; each mobile platform (i.e., aircraft) performs time-of-arrival (TOA) measurements on the mobile platform (i.e., aircraft) signals received by that mobile platform (i.e., aircraft) and also performs TOA measurements on the ground signal received by that mobile platform (i.e.

Abstract: A first transmitting device is used to transmit a first signal on a first carrier frequency to a relay device. The relay device receives the signal by demodulating the first carrier frequency. Subsequently, the relay device retransmits the signal by modulating a second and/or a third carrier frequency. The signal is then recovered at one or more receiving devices by demodulating the second and/or third carrier frequencies. Further, a second transmitting device transmits a second signal on a fourth carrier frequency and the relay device retransmits the signal by modulating a fifth and/or a sixth carrier frequency. The signal is then recovered at one or more receiving devices by demodulating the fifth and/or sixth carrier frequencies. The transmitting and/or receiving devices are preferably voice terminals, such as a wireless telephones or data terminals, such as portable computers.