Deutsche Telekom

About: Deutsche Telekom is a company organization based out in Welwyn Garden City, United Kingdom. It is known for research contribution in the topics: Telecommunications network & Signal. The organization has 3473 authors who have published 5208 publications receiving 65429 citations. The organization is also known as: DTAG & German Telecom.

Adaptive receiver for CDMA base stations

Abstract: An adaptive receiver for base stations of CDMA mobile wireless systems corresponding to the IS-95 Standard. The receiver is designed as an incoherent rake receiver and includes an antenna array. The receiver is capable of analyzing a plurality of components of the same signal transmitted by a mobile station arriving at the antenna array via different propagation paths and from different directions with a time offset. To form virtual antenna directivity patterns for individual rake processing paths, which are adjusted to the directions of incidence of the signal paths to be analyzed, direction signature vectors are calculated and made available to the processing paths together with a signal propagation time that is required for synchronizing the signal components. The direction signature vectors are calculated iteratively from the antenna correlation matrices formed recursively for all possible signal delay times from pulse responses of the antenna arrays. The signal components associated with the processing paths are selected according to the average path powers determined for the individual signal delay times, and the path powers are also calculated from the antenna correlation matrices.

Method and system for improvement of handover quality in mobile radio systems

Abstract: A handover method includes the steps: (1a) detecting, at a serving node, signal quality of a signal transmitted from the serving node to a user equipment (UE) being worse than a predefined threshold; (1b) identifying, at the serving node, node(s) transmitting to the UE the strongest signals interfering with signals being transmitted to the UE; (1c) sending, by the serving node, a request for starting an inter-cell interference coordination scheme; (1d) rescheduling, by the node(s) identified in step (1b), users currently being served by the node(s); (1e) informing, by the node(s) identified in step (1b), the serving node of the UE which resources have, been reserved in step (1d); (1f) scheduling, by the serving node, the UE to the resources reserved in step (1d); (1g) starting, by the serving node, handover of the UE from the serving node to a target node; and (1h) completing the handover of the UE.

Ablation of Si and Ge Using UV Femtosecond Laser Pulses

Abstract: Laser ablation of silicon and germanium was carried out in moderate vacuum with l00fs to 400fs pulses at 248nm and intensities up to 3x1013 W/cm2. Evidence for non-thermal material removal was found. Imaged multishot ablation patterns display the intensity dependentself-structuring effect, forming well-known columnar structures. It is shown that continued irradiation of these structures eventually results in comparatively clean ablation. An increase of ablation rate with depth was observed. The reason is an intensity enhancement inside the pits by reflective focussing to a level where bond-breaking takes place. Furthermore, it was noticed that ablation contours can be significantly improved by electrically grounding the target.

Device for implementing a block-ciphering process

Abstract: The invention relates to a device for implementing a block-ciphering process using an encryption/decryption arithmetic-logic module (3) which is supplied with the data stream of word length j≦n to be ciphered. The invention is characterized in that the arithmetic-logic module (3) includes a plurality of encryption/decryption elements (5), each of which forms a stage of a computing pipeline, the stages being designed such that they operate independently of each other in different modes of operation and with different keys. Supported by further components and data paths surrounding the encryption/decryption arithmetic-logic module (3), the invention allows up to p data streams, each with independently selectable word lengths j≦n and modes of operation, to be encrypted or decrypted simultaneously. In addition, the architecture of the device permits different logical data streams to be processed directly consecutively and free of conflict on the physical channels provided by the hardware resources.

Method and device for extracting signals out of a glass fiber

Abstract: In a method and a device for extracting signals out of a glass fiber without any detectable interference occurring, in particular without the signals propagating through the glass fiber experiencing any transmission loss, light that emerges laterally from the glass fiber due to scattering (Rayleigh scattering) processes, which are in existence anyway, is directed at a photodetector. In the process, the emerging light can be directed by focussing elements at the photodetector or at the input face of another glass fiber. In addition, the emerging light can be directed both directly as well as via at least one reflector at the photodetector.