Abstract: The present invention provides a time efficient and practical method for signal burst detection. The signal is first applied to a set of linear transformations and input to a one-bit analog to digital converter and stored. The stored signal is then correlated with stored replications of sinusoidal wave forms over the range of frequencies using either a random access memory (RAM) or EPROM chip. The maximum of the correlation outputs is then compared with a selected threshold to provide a decision for the existence or nonexistence of the signal. This information is used to signal the processor to proceed with the acquisition and processing of the signal to determine the frequency and phase.

Abstract: An audio/video system for encoding and decoding a video signal and a plurality of corresponding audio signals includes an encoder for receiving an input video signal, a first audio signal, and a plurality of second audio signals which correspond to the input video signal. The encoder combines the input video signal and the plurality of second audio signals to produce an encoded video signal but leaves the first audio signal substantially unchanged and then outputs the first audio signal and the encoded video signal. An audio/video signal communication device is connected to the encoder. The audio/video signal communication device accepts the encoded video signal and the first audio signal and transmits them to a decoder. The decoder separates the plurality of second audio signals from the encoded video signal leaving an unencoded video signal.

Abstract: Virtual circuits are routed and grouped into virtual paths during an interactive topology design process. Virtual circuits are assigned to virtual paths that provide minimum cost to each pass through a topology design. Virtual paths are dispersed into subgroups that minimize bandwidth consumption and maximize routing flexibility. This topology optimization process is constrained to minimize use of network resources.

Abstract: A hybrid network including a four port directional coupler with the terminating impedance of one port being intentionally mismatched with the characteristic impedance of the coupler. Such an intentionally mismatched port will cause the transfer signal of an input signal from an adjacent port to be reflected to another adjacent port and to be combined with the transfer signal of a second input signal, which is from an input port not isolated from the first input port. Placing the two input ports adjacent to one another also allows one input to radiate out of another adjacent input port. Alternately, a hybrid network is provided including a four port directional coupler with all ports properly terminated at the characteristic impedance of the coupler. An external combiner for signals from one port and its adjacent port allows the combining of two input transfer signals generated from the other two non-isolated input ports.