Abstract: A modular approach to the mapping of data in and from a standard SDH/SONET signal is described. A module has interfaces (T0-T8) which allows to connect to it to other of its kind and thereby achieving higher data rates, i.e. access to standard signals of higher levels. By choosing among different interconnection schemes, arrangements comprising a plurality of modules are also able to support concatenated data traffic.

Abstract: A fast n-bit to k-bit mapping or translation method and apparatus avoiding the use of content addressable memories (CAMs) is described. It essentially is characterized by using two conventional storage (RAMs). In the first storage (3), the n-bit words are stored preferably in an order determined by the binary search key. The second storage (4) holds the corresponding k-bit translations. Both storages are addressed by essentially the same address, which is established during the (binary) search performed to find a match between an input n-bit word and the contents of the first storage. In variants of the invention, the use of parallel comparisons and of pipelining is demonstrated.

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.

Abstract: For the multiplex transmission of coded speech signals in periodic frames, single segments (blocks of coded samples) are selectively suppressed for redundancy reduction, and are replaced on the receiver side by optimally correlated subsections of equal length from previously transmitted segments. On the transmitter side, a multiplicity of compare operations are made for each speech signal, between the respective newest coded segment and a step wise shifted subsection window of previous segments, to determine the best correlated subsection, i.e. the one which is most suitable as replacement and the respective relative offset and correlation. From a group of speech signals, the one signal, or several signals, having the best correlation is selected for suppression of a segment before transmission. Instead of each missing segment an indication of the corresponding optimum offset is transmitted in the frame header.

Abstract: In an extension line circuit, an off-hook condition is detected during ringing by superimposing in each ringing cycle the values of the line current existing at two sampling instants exactly one-half cycle apart, and testing whether the sum (or mean value) exceeds a given threshold. When DC current starts flowing due to the set going off-hook, the mean value of the two values will pass a threshold.Sample pulses for the sampling instants can be derived in common for all line circuits from positive-going zero crossings of the ringing supply signal.