Qualcomm

About: Qualcomm is a company organization based out in Farnborough, United Kingdom. It is known for research contribution in the topics: Wireless & Signal. The organization has 19408 authors who have published 38405 publications receiving 804693 citations. The organization is also known as: Qualcomm Incorporated & Qualcomm, Inc..

Layered channel element in a base station modem for a cdma cellular communication system

Abstract: The invention provides a layered channel software element (200) which supervises the operation of channel element modem resources (59) in a CDMA cellular telephone system (8) that includes forward channels (20a, 22a) for conveying message and signalling data from a CDMA system base station (12) to mobile units (16, 18) and reverse channels (20b, 22b) for conveying message and signalling data from mobile units (16, 18) to base stations (12, 14). Each channel is implemented in a channel element (59) including a general purpose processor (60) and a modem application-specific integrated circuit ASIC (62). The layered channel software element (200) executes on the general processor (60). The layered channel software element (200) provides a structure and function for transferring message and signalling data between the telecommunication system (10) and the modem ASIC (62) via channel element controller (44), and also for establishing channel operations by providing channel configuration information to the modem ASIC (62).

Systems, methods, and apparatus for enhanced acoustic imaging

Abstract: Methods, systems, and apparatus for using a psychoacoustic-bass-enhanced signal to drive an array of loudspeakers are disclosed.

Method and apparatus for updating rules governing the switching of virtual SIM service contracts

Abstract: A system and method for providing updated rules governing the switching of enabled provisioning data supporting a wireless service contract. A mobile device may be initially programmed with a profile data table and priority list index data table to automatically enable provisioning data supporting one of the plurality of service providers stored in a VSIM internal memory unit to conduct a wireless communication when certain operational parameter values are satisfied. The profile data table and priority list index data table may be automatically updated in response to a variety of triggers.

Transmission mode selection for data transmission in a multi-channel communication system

Abstract: Techniques to select a suitable transmission mode for a data transmission in a multi-channel communication system with multiple transmission channels having varying SNRs. In one method, an SNR estimate is initially obtained for each of multiple transmission channels used to transmit a data stream. An average SNR and an unbiased variance are then computed for the SNR estimates for the multiple transmission channels. A back-off factor is determined, for example, based on the SNR variance and a scaling factor. An operating SNR for the transmission channels is next computed based on the average SNR and the back-off factor. The transmission mode is then selected for the data stream based on the operating SNR. The selected transmission mode is associated with a highest required SNR that is less than or equal to the operating SNR. The method may be used for any system with multiple transmission channels having varying SNRs.

Distributed Relay-Assignment Protocols for Coverage Expansion in Cooperative Wireless Networks

Abstract: One important application of cooperative communications is to extend coverage area in wireless networks without increasing infrastructure. However, a crucial challenge in implementing cooperation protocols is how to select relay-source pairs. In this paper, we address this problem based on the knowledge of the users' spatial distribution which determines the channel statistics. We consider two scenarios at the destination node, when the receiver uses MRC and when no-MRC is used. First, we characterize the optimal relay location to minimize the outage probability. Then, we propose and analyze the performance of two schemes: a distributed nearest neighbor relay assignment in which users can act as relays, and an infrastructure-based relay-assignment protocol in which fixed relay nodes are deployed in the network to help the users forward their data. The outage probabilities of these two schemes are derived. We also derive universal lower bounds on the performance of relay-assignment protocols to serve as a benchmark for our proposed protocols. Numerical results reveal significant gains when applying the proposed simple distributed algorithms over direct transmission in terms of coverage area, transmit power, and spectral efficiency. At 1 percent outage probability, more than 200 percent increase in coverage area can be achieved, 7 dBW savings in the transmitted power, and the system can operate at 2 b/s/Hz higher spectral efficiency.