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.

Method for determining available frequencies in selective call receivers

Abstract: A selective call receiver (106) has a frequency synthesizer (708) for scanning a plurality of frequencies to determine a control channel to receive a signal and a receiver (704) for receiving the signal representative of an available frequency associated with a geographic region. The signal includes a channel identifier (404), a frequency assignment (406) and an active channel indicator (408). A processor (712) associates the channel identifier (404) with the frequency assignment (406) in response to the active channel indicator (408) indicating an availabe frequency of the geographic region and a memory (720) stores channel identifiers (404) associated with frequency assignments (406) designating available frequencies (408). The receiver (704) receives an address (333) and the channel identifier (404) on the control channel, a decoder (714) decodes the channel identifier (404) associated with the frequency assignment (406) to determine the available frequency where a message will be transmitted and the frequency synthesizer (708) switches to the available frequency indicated by the channel identifier (404) for receiving the message.

Ternary cam memory architecture and methodology

Abstract: The present invention encompasses a method of storing ternary data that includes the steps of (1) initializing a conversion register by storing binary-to-ternary mask data in a conversion register; (2) storing ternary data in a content addressable memory (CAM) by inputting a single bit binary data to the conversion register, and converting the binary data into two bits of ternary data using the conversion register; and (3) simultaneously storing the two bits of ternary data in first and second memory cells. For subsequent searching, the method further includes the steps of searching for a match of input search binary data to the stored contents of the CAM; providing a match valid output responsive to the input search binary bits matching any of the stored contents; and generating an address corresponding to a location in the CAM where the match is found.

Trunking system communication resource reuse method

Abstract: Reusing radio frequency specta in a trunked radio system by establishing small cell trunked radio systems within a large cell trunked radio system wherein low power radio transmission occurs permits multiple small cell trunked radio systems in geographically separate locatiosn to use a limited number of radio resources simultaneously, increasing usage of a finite number of communication resources. As used in cellular telephone systems, very low power trunked radio systems separated from each other can reuse the same frequency without interfering with each other or interfering with a large cell trunked radio system license holder.

Electromagnetic energy exposure of simulated users of portable cellular telephones

Abstract: Describes a method to quantify the RF exposure of the users of portable cellular phones in terms of specific absorption rate (SAR). The method involves a robotic system to accurately position an isotropic E-field probe within equivalent biological tissue. The user of cellular phones is simulated by a simple human model (a phantom) consisting of a thin shell of fibreglass filled with a liquid having the complex dielectric constant of human brain tissue. The authors present the results of the dosimetric assays conducted using current and previous models of cellular telephones. The peak SAR values detected using the measurement method described are below the limits recommended by the National Council for Radiation Protection and Measurements (NCRP) Report 86 for the protection of humans exposed to RF electromagnetic energy. >

On-chip error detection and correction system for an embedded non-volatile memory array and method of operation

Abstract: A microcontroller ( 100 ) has a CPU ( 102 ) and memory ( 104 ). Memory ( 104 ) contains a memory array ( 200 ). A large portion of the array ( 200 ) is used to contain functional data for the CPU ( 102 ), but the array ( 200 ) also contains one or a few rows of memory content parity information. Once the array ( 200 ) is written with lasting data and/or software, a parity controller ( 208 ) will generate initial parity values which correlate to the contents of the memory array ( 200 ). This parity information is stored within the parity portion of the array ( 200 ). After generating the initial parity data, the parity controller ( 208 ) occasionally, upon some parity checking event, generates current parity from the data stored within the array ( 200 ). This current parity is compared against the parity portion of the array ( 200 ) using the parity logic ( 210 ). If errors are detected, it is clear that the software/data that was intended to be static and non-changing has experienced a leakage error, soft error event, electrical short, etc. Once these errors are detected corrective measures may be taken to extend the reliable life of the product.