Abstract: Generating oscillator signals with which selected signals may be mixed. Such oscillator signals may be generated by dividing a pilot tone, such as a 120 MHz pilot tone found on many cable TV systems. Oscillator signals for demodulating received selected signals may be similarly generated.

Abstract: Generating oscillator signals with which selected signals may be mixed. Such oscillator signals may be generated by dividing a pilot tone, such as a 120 MHz pilot tone found on many cable TV systems. Oscillator signals for demodulating received selected signals may be similarly generated.

Abstract: Generating oscillator signals with which selected signals may be mixed. Such oscillator signals may be generated by dividing a pilot tone, such as a 120 MHz pilot tone found on many cable TV systems. Oscillator signals for demodulating received selected signals may be similarly generated.

Abstract: Generating oscillator signals with which selected signals may be mixed. Such oscillator signals may be generated by dividing a pilot tone, such as a 120 MHz pilot tone found on many cable TV systems. Oscillator signals for demodulating received selected signals may be similarly generated.

Abstract: System for distributing multimedia information from a central office to multiple subscriber premises includes an optical backbone for transmitting a plurality of optical bands from the central office into a vicinity of the subscriber premises. A controllable switch, positioned outside the subscriber premises, selects a subset of the plurality of optical bands and blocks others that are not contained within the subset, inducing the subset onto an optical transmission pathway. A receiver positioned within the subscriber premises receives at least one optical band of the subset. The controllable switch, in various embodiments, limits the information received at a subscriber premises to only the information to which the subscriber subscribes. In this manner, the need to scramble signals to prevent theft of services is eliminated, since subscribers only receive the services to which they subscribe.

Abstract: A telephone wire pair is qualified for digital signal transmission by central office testing. The tip-to-ring capacitance of the wire pair is measured while applying to the wire pair an AC test signal at 600 Hz. The test signal at this frequency minimizes errors due to line inductance and/or a ringing device connected to the wire pair. Reliable measurement of the length of the wire pair is achieved. Flaws in cable sheathing can also be detected based on measurement of tip-to-ground capacitance and/or ring-to-ground capacitance.

Abstract: A telephone wire pair is qualified for digital signal transmission by central office testing. The tip-to-ring capacitance of the wire pair is measured while applying to the wire pair an AC test signal at 600 Hz. The test signal at this frequency minimizes errors due to line inductance and/or a ringing device connected to the wire pair. Reliable measurement of the length of the wire pair is achieved. Flaws in cable sheathing can also be detected based on measurement of tip-to-ground capacitance and/or ring-to-ground capacitance.

Abstract: A point-to-multipoint radio broadcast communication system comprises a directional transmitter focused on a particular one of a plurality of receivers in a linear arrangement, such that the angle between each successively closer receiver and the transmitted beam increases as the distance between the transmitter/receiver pair decreases. Thus, a low-power directional transmitter can effectively transmit to a line of receivers due to the trade-off between a receiver being off-center and its closer proximity to the transmitter.