Patents Examined by Tracy M. Lagree
  • Patent number: 5878344
    Abstract: A multiple mode, personal, wireless communications system exists within a radiotelephone network serving general customers and provides additional services to a select group of customers. The system uses handsets (32) which automatically switch between a standard cellular radiotelephone mode of operation (1901) and an enhanced cordless mode (1420) when the handsets (32) are within range of pico cells (26) that are interconnected to the public switched telephone network (20). Each pico cell is controlled via a framework of overlay cells (10b) that operates independently of the radiotelephone network and uses a unique control protocol on a small number of reserved cellular channels. Each pico cell consists of a spectrally dynamic, non-capturing, frequency agile, multi-purpose base station (26) provided at customer-selected locations to cooperate with the overlay cell framework. Each pico cell is capable of supporting multiple handsets (32) and uses low power operation that achieves limited coverage.
    Type: Grant
    Filed: January 21, 1998
    Date of Patent: March 2, 1999
    Assignee: GTE Mobile Communications Service Corporation
    Inventor: Robert G. Zicker
  • Patent number: 5542029
    Abstract: The system and method disclosed herein relates to digital halftoning where a threshold array is used to control individual pixels in a halftone cell. The threshold array is replicated to tile the entire device space so that each pixel in device space is mapped to a particular location in the threshold array. By tiling the threshold array with overlap, the size of the overall threshold array is reduced. A CPU interface couples a FIFO buffer, registers, and RAM to a CPU for receiving pixel data, control signals and other values, respectively. An engine control unit is coupled to control a video processing unit and an output device for producing halftone images with a halftone matrix of reduced size. The engine control unit controls threshold logic that applies the threshold matrix to the pixel data to produce the data stream sent to the output device.
    Type: Grant
    Filed: September 30, 1993
    Date of Patent: July 30, 1996
    Assignee: Apple Computer, Inc.
    Inventor: Magnus L. Karlsson