Motorola Corporation

Other

Krsman Martinovich

Donald R Beyer

James Patrick Ashley

David G Wiatrowski

Lee Michael Proctor

Christopher N Kurby

Matthew Richard Miller

Gino Anthony Scribano

John Douglas Brophy

John P Monson

Christopher P Carey

Kent M Conness

A method of improving hard handoffs in a communication system comprising a source base station (BS), a target BSand a mobile switching center (MSC). In particular, when a handoff is needed, a requested service option and a list of service options supported by a mobile station (MS)are communicated from the source BS to the target BS. Upon receiving a handoff request message, the target base station selects either the requested service option or an alternate service option. The alternate service option is chosen based on one or more of the MS's service option capabilities, service option priorities, and resources available in the target BS. The selected service option is communicated to the source BS and the MS.

Method and apparatus for improving hard handoffs in CDMA systems

A method of reducing access to communication system resources by a fraudulent Mobile Station (). The Mobile Switching Center () sends a message to the Authentication Center () to invoke a first authentication procedure. The Authentication Center responds with a message including the results of the first procedure, and possibly, parameters for performance of an additional authentication procedure. Based on the contents of the message, the Mobile Switching Center decides whether to delay call setup until after the additional authentication procedure has completed successfully or whether to initiate call setup in parallel with the additional authentication procedure.

Method for reducing fraudulent system access

Vocoder bypass is provided using a combination of out-of-band and in-band signaling. In preferred embodiments of the present invention, two signaling channels are arranged for transmission within the compressed speech. Each of the signaling channels are communicated at a preferred rate to permit fast, reliable detection of conditions indicating vocoder bypass mode of operation and to synchronize and communicate compressed speech in a vocoder bypass mode of operation.

Method and apparatus for control of vocoder bypass utilizing inband

A method of providing operational features for a programmable radio (202) employs a security key (210). The security key (210) is preferably coupled to an interface device (208) and includes at least an indication of a desired feature set. Using this indication, or flashcode (220), the programming system is able to securely program (609) the radio (202) with the desired feature set (504).

Method and apparatus for secure programming of communication radios

A method of synchronizing a plurality of remote site transmitters (200) in a digital simulcast transmission system is described that enables use of four-level modulation on two-level modulation systems. A synchronization signal is transmitted at a predetermined data rate from a prime site, which signal might include a synchronization pattern having a first and a second portion. The first portion of the synchronization pattern is used for synchronization, while the second portion indicates the completion of the first portion. The method includes detecting (205, 320) of the first portion of the synchronization pattern. Each remote site transmitter (200) further has a modulation clock having a phase polarity which is selected (215, 324) in response to the detection of the first portion of the synchronization signal.

Synchronization method and apparatus for simulcast transmission system

A data transmission system receiver is disclosed which receives a formatted data stream (302) and operates in one of at least a first bandwidth mode and a second bandwidth mode. The formatted data stream (302) comprises a plurality of data edges (108, 110) and is sampled by a first clock signal (320). A plurality of clock edges (102, 104) defining transitions from one logic state to another is used to define 'early' and 'late' data edge occurrences. These occurrences are accumulated in accumulators (310, 312) and used as inputs to a clock counter (318) which produces a phase-adjusted clock signal (320). Additionally, the data transmission receiver comprises a detector (330) for detecting when a limited data stream (306) is synchronized with the phase-adjusted clock signal (320) and, in accordance with a predetermined algorithm, is able to switch the phase-lock circuit from the first bandwidth mode to the second bandwidth mode.

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Streamwood, IL, United States of America

Krsman Martinovich