Motorola Corporation

Motorola Solutions, Inc.

Marc W Cassidy

Daniel J McDonald

Tanhoa Trandai

Donald R Griffis

David R Mills

John M Gilbert

Randy L Ekl

Andor Almasi

Michael C Petrie

Gregory A Feeney

Gary P Hunsberger

John T Mistro

Erick Loven

Daniel J Mcdonald

A system and method for processing calls in a communication system utilizing distributed signaling. When a call signal having distributed identification data is received on a communication channel, the call information (such a voice, data, video, etc.) is initially passed through the system without verification until sufficient identification data (such as the color code) has been obtained to determine whether the source of the call is valid. Once sufficient identification data has been obtained, the source is verified. If the source is valid, the call information continues to be passed through the system. However, if source is invalid, the call information is blocked for the present call as well as for subsequent calls on the same communication channel, and passing of the call information through the system does not resume until a received call is subsequently assessed to be valid.

System and method for minimizing undesired audio in a communication system utilizing distributed signaling

A receiving device in a trunked radio communications system determines a transmit frequency, wherein the transmit frequency is calculated by subtracting a voice channel number from 759, multiplying by a channel spacing and adding a base frequency to yield the transmit frequency. The receiving device determines a receive frequency by a base frequency+[(759&#x2212;a voice channel number)*25,000 Hz], where the base frequency is at least one of 851.0125 MHz, 851.0250 MHz, and 851.000 MHz. In any case, the voice channel number is communicated in an outbound signaling message defined by Motorola's 3600-baud radio trunking protocol.

Method for preventing an unauthorized device from operating in a 800 MHz trunked radio communications system

A receiving device in a trunked radio communications system determines a transmit frequency, wherein the transmit frequency is calculated by subtracting a voice channel number from 559, multiplying by a channel spacing and adding a base frequency to yield the transmit frequency, if the voice channel number is between 559 and 320. The receiving device determines a receive frequency by 851.0250 MHz+[(559&#x2212;a voice channel number)*12,500 Hz], if the voice channel number is between 559 and 320. In any case, the voice channel number is communicated in an outbound signaling message defined by Motorola's 3600-baud radio trunking protocol.

Method for preventing an unauthorized device from operating in an 800 MHz trunked radio communications system using channels 559 to 320

A receiving device in a trunked radio communications system determines a transmit frequency, wherein the transmit frequency is calculated by subtracting a voice channel number from 319, multiplying by a channel spacing and adding a base frequency to yield the transmit frequency, if the voice channel number is between 319 and 0. The receiving device determines a receive frequency by 851.0125 MHz+[(319&#x2212;a voice channel number)*25,000 Hz], if the voice channel number is between 319 and 0. In any case, the voice channel number is communicated in an outbound signaling message defined by Motorola's 3600-baud radio trunking protocol.

Method for preventing an unauthorized device from operating in an 800 MHz trunked radio communications system using channels 319 to 0

A receiving device in a trunked radio communications system retrieves a first frequency from a scan list and tunes to about the first frequency. If no control channel messages are decoded at the first frequency, then the receiving device tunes to about a second frequency. If no control channel messages are decoded at the second frequency, then the receiving device iterates through the scan list, until the last frequency in the scan list is reached, wherein the scan list comprises control channels for at least two band plans.

Method for determining a control channel in a trunked radio communications system utilizing a scan list

A receiving device in a trunked radio communications system retrieves a first frequency, wherein the first frequency relates to a lowest frequency that the at least one repeater utilizes for transmission and tunes to about the first frequency. If no control channel messages are decoded at the first frequency, then the receiving device tunes to about a second frequency wherein the second frequency is a channel separation of 12.5 kHz from the first frequency. If no control channel messages are decoded at the second frequency, then the receiving device, iteratively increments the second frequency by the channel separation until the second frequency reaches an end of band frequency for the trunked radio communications system.

Method for determining a control channel in a trunked radio communications system

A method of registration in a communication system includes the steps of detecting ( ) an elevated registration level of at least a part of a communication system, selecting ( ) a group recovery time, determining ( ) a first random registration time that is less than or equal to the group recovery time, registering ( ) a first communication unit ( ) from a first talkgroup at the first random registration time, and upon receiving ( ) a group activity message for the first talkgroup, delaying ( ) registration by at least a second communication unit ( ) from the first talkgroup.

Method of registration in a communication system

A method of registration in a communication system includes the steps of detecting (201) an elevated registration level of at least a part of a communication system, selecting (203) a group recovery time, determining (205) a first random registration time that is less than or equal to the group recovery time, registering (209) a first communication unit (111) from a first talkgroup at the first random registration time, and upon receiving (212) a group activity message for the first talkgroup, delaying (213) registration by at least a second communication unit (113) from the first talkgroup.

Growing community of inventors

Fox River Grove, IL, United States of America

Marc W Cassidy