Abstract: Channel impulse response estimation employs a training sequence to enable correction for multipath and other disturbances affecting a signal during transmission via a digital wireless communication channel. High-speed packet transmission rates, with a training sequence for each packet, are made possible by training sequence construction enabling fast algorithm processing of received signals for impulse response estimation. Upon reception, a Toeplitz-type mathematical representation is constructed based on transmitted and received versions of a training sequence. The Toeplitz-type representation may then be processed by application of fast algorithms, such as Levinson-type algorithms, to determine coefficients representative of the communication channel impulse response. These coefficients, applied to an adaptive equalizer type of filter, enable correction for signal disturbances incurred in transmission. Channel impulse response estimation methods and systems are described.

Abstract: A system and method for providing automatic path selection in a fiber-optic transmission network. The system provides efficient utilization of available bandwidth with respect to T1, T3 and STS-3c service requests. A time slot is selected from the available time slots in a maximally utilized and efficient manner in response to a type of service request. The time slot is then assigned to the service request to provide a transmission pathway. In response to a T1 service request, the system finds the most occupied time slot which has an available assignable time slot. If a new unoccupied time slot is required or the request is for a T3 or a STS-3c service, the system selects an unoccupied time slot in accordance with a prioritized order of contiguous unoccupied time slots.

Abstract: An operating system is provided for an analog switching machine having switch fabric formed by multiple line and trunk link networks having interconnected switch stages with each switch stage having multiple grid connections and makes post-connection continuity checks. Error messages are generated for connection faults and sent to a monitor and analyzer computer. The error messages are automatically processed to identify the root causes of connection faults, i.e. to detect open and stuck crosspoints, faulty interstage links and faulty pulse path devices. The analyzer computer further generates command signals that provide for removal of faulty crosspoints and other failed elements from analog switching machine operation.

Abstract: A digital signal processor is provided with the facility to range and converge on each of a plurality of echoes occurring at respective locations along a communications line. Specifically, the digital signal processor is arranged to adaptively process samples of a signal that has been transmitted to the communications line correlated with samples of a signal that have been received from the communications line. In the processing of the samples, the digital signal processor separates and measures the magnitude of each echo that it converges on, beginning with a so-called near-end echo. In addition, the digital signal processor calculates the propagation delay of each echo that it converges on using the number of sampling intervals that have been processed in order to position the processor on the dispersion of that echo.