Abstract: Viterbi detector for a channel having a memory length 1, where no more than two survivors with an associated difference metric are updated. In the prior-art Viterbi detector of this type the new difference metric is derived using a saturation function from the previous difference metric. If the amplitude of the received signal differs from the values assumed for the calculation of the difference metric, the performance of the prior-art detector will rapidly degrade. In the detector according to the invention the new difference metric is derived from a saturation function of the previous difference metric, with the size of the linear region being dependent on the magnitude of the amplitude of the received signal.

Abstract: With cordless telephones it is a known fact that each pair of radio stations has m radio channels out of n possible radio channels in common. During a test cycle the mobile unit examines only the common radio channels. Consequently, the test period required for testing only the common channels is shorter than the time necessary for testing all channels. If, by chance, all common channels are busy or if such a situation is the result of a malfunctioning, establishing a link between the base unit and the mobile unit is no longer possible. In the proposed embodiment of a cordless telephone, reliably establishing a link is guaranteed in that in a first test phase the common channels and in a second test phase all n radio channels are tested. A field of application of the invention is the cordless telephone.

Abstract: An application module of a data processing apparatus requires various quantities of memory space for the buffering of data to be processed. In particular, image and audio files are to be read from a CD-ROM disc and decoded in real-time. The operating system provides a memory manager to allocate buffer space from the available memory. To alleviate the problem of fragmentation, a fragmented memory manager module secures at the outset an allocation of buffer space sufficient for all requirements of the application module, and partitions the allocation into small units of buffer space (fragments), which are linked into a list by respective list pointers. Any subsequent requirement for buffer space is met by the fragmented memory manager, by un-linking the requisite number of fragments from the list of unallocated fragments. The application module is adapted to use fragmented buffer space where possible, while the allocation of buffer space in contiguous blocks is not excluded when necessary.

Abstract: An ATM switching arrangement in which two types of cells are distinguished. A first type of cells is marked as low loss cells and a second type of cells is marked as low delay cells. In the switching arrangement a cell buffer (9) is subdivided into a first memory area (LL) for the low loss cells and a second area (LD) for the low delay cells. In the case of the cell buffer (9) being completely filled, low loss cells get read-in priority over low delay cells. In reading out from the cell buffer low delay cells take priority over low loss cells, unless the low delay area is empty. It is also possible to set a threshold value for the content of the low loss area; when the content of the low loss area exceeds the threshold value outputting of the low loss cells can then be started.

Abstract: A genetic algorithm is used to search for optimal configurations of a computer controlled pick and place machine, which places parts on printed circuit boards. Configurations include: assigning grippers to pipettes of the machine; assigning parts, destined for the printed circuit boards, to feeders of the machine; assigning parts to pipettes; and determining time intervals and orders in which parts are to be placed. The genetic algorithm is applied to chromosome strings representing parameters for determining machine configuration. A heuristic layout generator generates machine configurations from the chromosome strings.

Abstract: To prevent light scattering at the edges of CRT's used in projection television, emission of light is prevented beyond a desired region of raster scanning. In one embodiment, portions of the front surfaces of the CRT's outside the desired region are darkened to prevent light emission.

Abstract: A document handling system comprises physical presentation means for receiving, presenting, and removing a document with respect to the system. Furthermore, it is provided with scanning means for the document and printing means for printing on an unprinted sheet a document that contains a form. The form contains a plurality of physically sparse format calibrating items at a perimeter of the form, directly machine-readable form identifier dam in a prescribed identifier field, and form content data including user completable indicia boxes proper to the form so identified. The form can be used for generating a facsimile sheet inclusive of standard facsimile header, for generating a standard document for general use, or for allowing a user to input amending data for inclusion into a later to be printed user specifiable document.

Abstract: Method of processing signal data on the basis of Principal Component Transform, apparatus for performing the method. A method is proposed for determining approximations of eigenvectors of a covariance matrix associated with signal data on the basis of the Principal Component Transform. Successive iterations on estimates enhance the development into the direction of the principal component considered. The method is applicable to the Singular Value Decomposition of data matrices. The operations to be performed are similar to those required in a neural net for adapting the synaptic coefficients. Apparatus are proposed for performing the method.

Abstract: An electron-optical system directs an electron beam which emanates, for example from a line-shaped or annular emissive cathode element, onto an anode target face in a collimated fashion so that a large part of reflected electrons is incident on the target face again, thus contributing to the generating of X-rays. The construction of the electron-optical system and the high degree of re-incidence of scattered electrons allows for a minimum distance between the anode target face and the exit window. A filament of the cathode may be constructed so as to achieve an optimally uniform operating temperature over a comparatively large part of its length.

Abstract: There is described a multimodule data processing system with N fully interconnected data processing modules for executing a Dispersed Joined Communication method according to a K-level nested and level-wise compartimentalized encoding, broadcasting and decoding operation. This allows for protecting against at most T maliciously operating modules, wherein K=T+1. At level K all said N modules are situated in a single compartment. At level k=1 for any extant message in any actual module such extant message is broadcast to all modules present in that message's compartment. For any level K+1>k>1 said operation previously comprises for any extant message generating therefrom n>2T symbols according to a T-symbol error correcting encoding and within that message's actual compartment transmitting each of such n symbols as messages to a respective different module. Those different modules together constitute a next lower-level compartment for therein executing said operation according to next lower level k-1.

Abstract: A channel data transmission system is described, which data are structured channel-sequentially in frames and/or multiple frames. Such transmission systems are used, for example, for video conferencing during which data are exchanged over ISDN base channels. Since the bit rate, at which video codecs exchange their data, exceeds the bit rate, at which data can be transmitted over a base channel, no less than two base channels are to be provided for the intended data exchange. The signals of these base channels may be variably delayed on their way to the receiver. Cancelling this delay difference for a maximum of thirty base channels is the essential object of the multiplexer described. For achieving this object the received data (1a) of the base channels are channel-sequentially arranged and written in an addressable main memory (3). Detection means (11, 13, 13A, 14, 15, 16) are to detect frames and multiple frames among the stored data of one of each of the channels.

Abstract: A circuit for adjusting the bit rates of two signals is necessary for plesiochronous multiplexers, for example, to bring the plesiochronous signals, which are to be combined to one digital signal of the next higher hierarchy, to the same bit rate. For this purpose, the circuit arrangement comprises an elastic store (4) as well as a justification decision circuit (15, 16). In order that a circuit having such features can be used for bit rates of the order of 140 Mbit/s and yet can be arranged largely in CMOS technology, the bit clocks of the first and second signals are reduced at the ratio of 1:n. Furthermore, a serial-to-parallel converter (2) converts bit groups of n serial bits of a first signal into bit groups of n parallel bits, which are written in groups into the elastic store (4) and are also read out in groups. The parallel bit groups read out are applied to a controllable selection matrix (5) having n outputs, which transmits n selected bits of more than one bit group to n outputs.

Abstract: For avoiding error propagation as a result of decision feedback equalization, the data to be transmitted are coded with a coder 2 which has a transfer function substantially inverse to the transfer function of the channel 4. Consequently, instantaneous decisions about the received symbol may be made at the receiver 6 without intersymbol interference causing a disturbance. If the channel transfer function differs from the transfer function of the precoder 2, intersymbol interference will again occur, so that the symbol error rate will increase. In order to restrict this increase of the symbol error rate as much as possible, the receiver comprises a cascaded circuit of an adaptive filter 18 which has an inverse transfer function to that of the channel and a decoder 21 which has an inverse transfer function to that of the precoder 2.

Abstract: A telephone system in which communication between fixedly sited primary stations and transportable secondary stations is by way of respective time division duplex (TDD) radio links, particularly single frequency TDD links. In order to reduce radio interference between closely sited primary stations, their transmit periods are frame synchronized by using an externally produced radio signal. Conveniently a broadcast television field synchronization signal can be used.

Abstract: In an X-ray tube for an X-ray analysis apparatus an optimized minimum working distance is achieved, together with an adequately high radiation yield, by integrated optimization of the radiation end of the tube, the position and the mounting of the exit window, and the electron-optical configuration in the tube. This results in an X-ray tube having a conical end, an angle of cone of approximately 45.degree. and the use of the cone as such in the electron-optical system of the tube. Exact determination of the anode position relative to a reference face outside the tube enables exact positioning of each individual tube in an analysis apparatus.

Abstract: A circuit arrangement for adapting the bit rates of two signals to each other comprises an elastic store (6). The useful data of a first frame-structured signal are written into this store (6) by means of a write address counter (7) and read out again by means of a read address counter (8). A phase comparator (16) is used for comparing the counts of these counters (7, 8). In order to largely avoid jitter in the signal that has been read, the read address counter (8) and the phase comparator (16) are incorporated in a control circuit that controls the clock for the read address counter (8). In this control circuit the output signal of the phase comparator (16) is the control error. The controlled system (17) of the control circuit consists of a controllable oscillator circuit with whose output signal and read address counter (8) is clocked. In order to avoid stationary phase shifts with a constant frequency shift, a controller (18) having a PI behavior (PI=proportionality and integration) is used.

Abstract: A digital pre-modulation filter with a finite impulse response having the value k(t)=h(t).multidot.w(t), where h(t) represents an impulse response of the type that is customary for a modulator, for generating in response to data signals an angle-modulated carrier signal having a substantially constant amplitude, and w(t) represents a window function by which the impulse response of the pre-modulation filter is truncated softly. It turns out to be possible to reduce the disturbing effects with respect to the power spectrum caused by such a soft truncation and cancel them with respect to the phase of the angle-modulated carrier signal. Thereto, according to the invention the impulse response k(t)=A{g(t)+x(t)}.multidot.w(t) is selected where A is a correction factor which is usually equal to one, g(t) is the untruncated impulse response of the filter, x(t) is a constant c.sub.

Abstract: Multicomputer systems frequently consist of a network of node computers connected to one another in a particular topology, and at least one host computer which controls the network. To execute a task, the host computer loads a program into the node computer, and this is then followed by data, either from the host computer or possibly from a peripheral device also connected to the network, which are processed in accordance with the loaded program.

Abstract: A diagonally oriented LCD panel is used in a rear screen LCD projection television to reduce moire fringes on the display.

Abstract: A program-controlled processing device includes a multiport memory circuit providing a plurality of storage locations. First and second data ports of the memory circuit provide parallel access to different locations in accordance with first and second addresses encoded in the program instructions. Bypass means is provided for coupling the second data port to the first data port to simulate parallel access to the same location when desired. The bypass means is controlled directly by the program instructions, by means of a separate bypass control field or by a special value of one of the two addresses. There is thus no need for a run-time comparison of addresses before each memory access, leading to a faster operation of the memory circuit.