U.S. Philips Corporation

Telefonaktiebolaget Lm Ericsson (publ)

Stefan Muller

Johannes B Huber

Georg Kammler

Robert Fischer

Wolfgang Gerstacker

Raimund Meyer

Robert Bauml

The major problem in multicarrier transmission procedures consists in the very high crest factor of the transmit signal. This means, that very high signal peak values occur even with a moderate transmission power. It is the object of the invention to provide a method and device, whereby a definite reduction of signal peaks is achieved with moderate expenditure. This is obtained by generating, in addition to the information to be transmitted, several alternative, information-equivalent information sequences by means of determined reversible unambiguous representations. From these alternatives a sequence being favorable in view of the peak value of the pertinent transmit signal is selected and transmitted. The receiver is in a position to regenerate the original information from said receiving signal through the inversion of the performed representation.

Method and device for reducing the crest factor in digital transmission

The invention relates to a digital transmission system comprising a receiver, in which system a trellis-based estimation method (3) with a number of states reduced as a result of feedback (5) of at least one feedback value (.xi.) forms estimates (a) for a received signal (r) by means of an estimated impulse response (h) of a transmission system (1), a feedback value (.xi.) being determined from at least one estimate (a). With reduced-state estimation methods for the digital transmission, the problem consists of the additional noise components caused by the feedback of preliminary false symbol decisions. To achieve optimum estimates (a) for the received signal (r) despite a reduced number of states due to feedback, the receiver forms the feedback value (.xi.) from at least one intermediate value (a.sub.SDF). In digital transmission systems, the transmit symbols (a) and the estimates (a) have the values -1 or 1 in the receiver. In the receiver according to the invention, intermediate values (a.sub.SDF) having a value in the range from -1 to 1 can be fed back, so that a better feedback value (.xi.) and thus better estimates (a) for the received signal (r) may be achieved.

Digital transmission system with a trellis-based, reduced-state

A method for outsert molding a movable plastic part on a metal plate, wherein the movability is obtained automatically through the shrinkage of the plastic. The plastic part consists of a bridge element which traverses a hole in the metal plate and is integrally connected to opposing retaining elements by a film element. The size, shape, and rigidity of the film, bridge, and retaining elements are such that the forces produced during the shrinkage process lift the retaining elements off the metal plate.

Method of producing a movable plastic part on a metal plate

A technical device, particularly an electromechanical deck for moving information carriers, has at least one plastics function part (25) formed on a metal plate, which part has been moulded onto the metal plate (8) by outsert-moulding and comprises at least one bridge element (28), which traverses a hole (26) in the metal plate (8), and retaining elements (30, 31), which are situated on the metal-plate surfaces (8a, 8b) and are interconnected by the bridge element (28), the movability of the function part (25) as a slidable or rotatable part being obtained automatically through shrinkage of the plastic by the following construction:

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Erlangen, Germany

Stefan Muller