Motorola

About: Motorola is a company organization based out in Schaumburg, Illinois, United States. It is known for research contribution in the topics: Signal & Communications system. The organization has 27298 authors who have published 38274 publications receiving 968710 citations. The organization is also known as: Motorola, Inc. & Galvin Manufacturing Corporation.

Hierarchical analysis of power distribution networks

Abstract: Careful design and verification of the power distribution network of a chip are of critical importance to ensure its reliable performance. With the increasing number of transistors on a chip, the size of the power network has grown so large as to make the verification task very challenging. The available computational power and memory resources impose limitations on the size of networks that can be analyzed using currently known techniques. Many of today's designs have power networks that are too large to be analyzed in the traditional way as flat networks. In this paper, we propose a hierarchical analysis technique to overcome the aforesaid capacity limitation. We present a new technique for analyzing a power grid using macromodels that are created for a set of partitions of the grid. Efficient numerical techniques for the computation and sparsification of the port admittance matrices of the macromodels are presented. A novel sparsification technique using a 0-1 integer linear programming formulation is proposed to achieve superior sparsification for a specified error. The run-time and memory efficiency of the proposed method are illustrated on industrial designs. It is shown that even for a 60 million-node power grid, our approach allows for an efficient analysis, whereas previous approaches have been unable to handle power grids of such size.

A hierarchical approach to color image segmentation using homogeneity

Abstract: In this paper, a novel hierarchical approach to color image segmentation is studied. We extend the general idea of a histogram to the homogeneity domain. In the first phase of the segmentation, uniform regions are identified via multilevel thresholding on a homogeneity histogram. While we process the homogeneity histogram, both local and global information is taken into consideration. This is particularly helpful in taking care of small objects and local variation of color images. An efficient peak-finding algorithm is employed to identify the most significant peaks of the histogram. In the second phase, we perform histogram analysis on the color feature hue for each uniform region obtained in the first phase. We successfully remove about 99.7% singularity off the original images by redefining the hue values for the unstable points according to the local information. After the hierarchical segmentation is performed, a region merging process is employed to avoid over-segmentation. CIE(L*a*b*) color space is used to measure the color difference. Experimental results have demonstrated the effectiveness and superiority of the proposed method after an extensive set of color images was tested.

Downlink scheduling and resource allocation for OFDM systems

Abstract: We consider scheduling and resource allocation for the downlink of a cellular OFDM system, with various practical considerations including integer tone allocations, different sub-channelization schemes, maximum SNR constraint per tone, and "self-noise" due to channel estimation errors and phase noise. During each time-slot a subset of users must be scheduled, and the available tones and transmission power must be allocated among them. Employing a gradient-based scheduling scheme presented in earlier papers reduces this to an optimization problem to be solved in each time-slot. Using a dual formulation, we give an optimal algorithm for this problem when multiple users can time-share each tone. We then give several low complexity heuristics that enforce integer tone allocations. Simulations are used to compare the performance of different algorithms.

Secure wireless electronic-commerce system with wireless network domain

Abstract: A method of conducting transactions in a wireless electronic commerce system, where the system comprises a wireless network operator certification authority (15) having a root public key certificate and at least one attribute authority (404, 405, 406) having a digital certificate that is dependent from the root public key certificate. The attribute authority is accessible by a wireless client device (11) via a wireless network. The digital certificate is delivered from the attribute authority to the wireless device, the attribute authority is verified to the wireless client device using the digital certificate and the root public key certificate preloaded in the wireless client device under authority of the wireless network operator. An attribute (software, service, right/permission or other content item) is delivered to the wireless client device over the wireless network and ultimately enabled at the wireless client device.

Vehicle monitoring arrangement and system

Abstract: A vehicle monitoring system is described having an arrangement (14,16) installed within a vehicle, wherein the system includes an external data terminal for communicating information to a remotely located base station (12). The arrangement includes a plurality of communication modules (36), each being capable of communicating messages associated with performance of the vehicle; a data bus member (44) for electrically intercoupling the plurality of communication modules (36) and for receiving the communicated messages therefrom; a driver interface module (28) for transmitting messages to and for receiving messages from a vehicle operator; and a recorder (26) coupled to the data bus member (44) for recording information associated with performance of the vehicle which has been transmitted over the data bus member (44) by the plurality of communication modules (36), coupled to the driver interface module (28) via a second data bus member (30) for transferring messages therebetween. The external data port (24) is provided by the recorder (26) and is used for communicating messages with the base station (12), preferably over an RF link.