Abstract: The present invention provides apparatus and methods for determining a propagation time of a signal transmitted from a first location to a second location as a request signal and received as a response signal by the first location via a channel. In an example embodiment, a method comprises the step of determining the propagation time of the signal based on a local counter value that represents the time between transmission of the request signal and reception of the response signal, a remote counter value that depends on the request signal and being known to the first location, and a determinable time-delay value. The remote counter value represents an inter-time-delay between the reception of the request signal and the start of transmission of the response signal at the second location.

Abstract: The present invention provides apparatus and methods for determining a propagation time of a signal transmitted from a first location to a second location as a request signal and received as a response signal by the first location via a channel. In an example embodiment, a method comprises the step of determining the propagation time of the signal based on a local counter value that represents the time between transmission of the request signal and reception of the response signal, a remote counter value that depends on the request signal and being known to the first location, and a determinable time-delay value. The remote counter value represents an inter-time-delay between the reception of the request signal and the start of transmission of the response signal at the second location.

Abstract: The present application makes use of a novel adaptive noise-predictive partial-response equalization scheme for channels (30) exhibiting spectral nulls and/or near nulls. The noise-predictive partial-response (PR) equalizer employed in the different embodiments of the present invention consists of a linear PR equalizer (32) which shapes the channel response to a predetermined partial-response function, followed by a linear predictor. This scheme modifies the output sequence of said linear partial-response equalizer (32) by whitening the total distortion, i.e. by whitening the noise components and the residual interference components at said linear PR equalizer output, thereby achieving the best possible signal-to-noise ratio (SNR) before detection.

Abstract: A method and apparatus are disclosed which, for obtaining the quotient of division operations in a data processing apparatus, generate as an auxiliary value the inverse square root g of the divisor w. The auxiliary value g is then multiplied by the divident v, and the intermediate result again multiplied by the auxiliary value g. An improvement in operation of the data processing apparatus is obtained despite introduction of the auxiliary value because the range covered by the auxiliary value is significantly smaller than that of the direct inverse of the divisor. A preferred application is the area of signal processing in communications.

Abstract: A sensor, having a plurality of parallel elongated light transducers, is rotated relative to a document to be aligned with a predetermined reference. A signal accumulated from the transducers reaches a distinct maximum when printed lines on the document are aligned with the elongated transducers. Detection of this maximum enables measurement of the angle by which the document is out of alignment.