U.S. Philips Corporation

Lucent Technologies Inc.

Fraunhofer-Gesellschaft Zur Foerderung Der Angewandten Forschung E.V.

Alcatel

U.S. Phillips Corporation

Com-research Gmbh

Broadband United Gmbh

Wolfgang Gerstacker

Johannes B Huber

Raimund Meyer

Robert Fischer

Peter Schramm

Robert Schober

Josef Bernhard

Gerd Kilian

Rainer Walter Bachl

Axel Busboom

Patrick Nickel

Wolfgang Koch

Ulrich Berold

Stefan Muller

Andreas Tasch

Georg Herrmann

J&uuml;rgen Petersen

Roman Tzschoppe

Richard Rau

Johannes Huber

Axel Broll

Concept for transmitting payload data from a transmitter to a receiver via a communication channel within a time interval, wherein channel-coded data packets are generated from the payload data, wherein each of the channel-coded data packets has packet core data corresponding to a packet identification of the respective channel-coded data packet, and wherein the packet core data is coded with a channel code of higher redundancy than the payload data. The channel-coded data packets are sent without any return channel to the receiver, which decodes packet core data of a first received channel-coded data packet of the time interval. If error-free decoding of the first channel-coded data packet fails, packet core data of at least one second received channel-coded data packet of the time interval are decoded to determine a suitable further channel-coded data packet for combination with the first channel-coded data packet to acquire, on account of the combination, an increased code gain for decoding of the payload data.

Concept for combining coded data packets

The invention relates in general to systems for digital transmission, for example digital mobile radio systems such as the UMTS (Universal Mobile Telecommunications System) and in particular to the receiving-end estimation of parameters which are required for retrieving the data. An object of the invention resides, in particular, in indicating an efficient way which, particularly in the case of CDMA systems with power control, ensures estimates of higher quality than with methods of the prior art, and simultaneously largely avoids a substantial increase in the complexity of system implementation. For this purpose, the invention proposes a method for improving the reception of a CDMA receiver based on a parameter estimation method, as well as a correspondingly adapted CDMA receiver, in which the estimates are produced by processing received values (y[k]) provided with correction factors (s), the correction factors (s) serving to equalize different power levels of the received signal.

Method for improving the reception of a CDMA receiver, and a CDMA receiver with improved reception

A method for interference suppression for TDMA and/or FDMA transmission, which at least approximately can be described as pulse amplitude modulation, with an arbitrary number of receive antennas. The method comprises filtering of at least one complex-valued received signal r[k] of one receive antenna with a filter with complex-valued coefficients f[k] for generation of at least one output signal y[k], forming at least one projection of at least one output signal y[k] onto a vector pwhich is assigned to this output signal y[k], summing of a majority, especially all of the output signals y[k] for forming a sum signal s[k], and feeding the sum signal s[k] into a device for detection, especially equalization. A system for interference suppression for TDMA and/or FDMA transmission is also disclosed.

Method for interference suppression for TDMA -and/or FDMA transmission

A method is described for digital transmission of information over copper lines wherein digital signals are precoded by a fixed precoder on a transmitter side and are recovered by blind equalization on a receiver side. The blind equalization is subdivided into an equalization of the magnitude and a subsequent equalization of the phase.

Method for digital transmission of information

The invention relates to a receiver for a digital transmission system with an incoherent transmission method, which receiver includes an equalizer for forming estimates for a sequence of symbols a&lsqb;k&rsqb; transmitted by a transmission channel from received symbols r&lsqb;k&rsqb; by means of an impulse response h&lsqb;k&rsqb; that describes the transmission properties. For improving the receiving quality in an incoherent transmission method and transmission channels having intersymbol interference, it is proposed that the equalizer performs an incoherent maximum likelihood sequence estimation (MLSE) method to determine the estimates &acirc;&lsqb;k&rsqb; for the sequence of transmitted symbols a&lsqb;k&rsqb;. In channels having intersymbol interference, the incoherent MLSE method provides clearly better results than all the known incoherent receiving methods. As against frequency and phase offset, the incoherent MLSE method is considerably more robust than all the known coherent receiving methods. An expensive frequency and phase control may be omitted in this manner.

Receiver for a digital transmission system

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

Equalizer with a sequence estimation method with state reduction for a

Equalizer with extended channel estimation for a receiver in a digital

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Nuremberg, Germany

Wolfgang Gerstacker