Browse Prior Art Database

METHOD OF MAINTAINING QUEUED CALL REQUESTS DURING REPLACEMENT OF CONTROL CHANNEL FREQUENCY

IP.com Disclosure Number: IPCOM000007936D
Original Publication Date: 1996-Nov-01
Included in the Prior Art Database: 2002-May-07
Document File: 5 page(s) / 182K

Publishing Venue

Motorola

Related People

Alan Grau: AUTHOR [+2]

Abstract

A wireless, trunked communication systems, as illustrated in Figure 1, consists of a communication controller, an Operations and Maintenance Center (OMC) or Man Machine Interface (MMI), a num- ber of base stations connected to the communica- tion controller via a Local Area Network (LAN), and a number of mobile subscriber units, such as radios or cellular telephones. Each of the base sta- tions provide a plurality of communication chan- nels. One of the base stations provides a control chan- nel and several traffic channels, while the remaining base stations provide trafhc channels only. Mobile radio system access and control occurs over the con- trol channel. The control channel carries most of the control-related messages in the system includ- ing, but not limited to: origination requests, chan- nel assignments, power control, time alignment, sys- tem configuration, and system resource availability. The communication controller will respond to call requests received over the control channel with either a channel assigned message assigning the requesting subscriber unit a channel for communication, or with a request queued message to the requesting mobile subscriber, queueing the request pending resource availability.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 41% of the total text.

Page 1 of 5

Technical Developments

METHOD OF MAINTAINING QUEUED CALL REQUESTS DURING REPLACEMENT OF CONTROL CHANNEL FREQUENCY

by Alan Grau and Bob Clinkert

INTRODUCTION

  A wireless, trunked communication systems, as illustrated in Figure 1, consists of a communication controller, an Operations and Maintenance Center (OMC) or Man Machine Interface (MMI), a num- ber of base stations connected to the communica- tion controller via a Local Area Network (LAN), and a number of mobile subscriber units, such as radios or cellular telephones. Each of the base sta- tions provide a plurality of communication chan- nels. One of the base stations provides a control chan- nel and several traffic channels, while the remaining base stations provide trafhc channels only. Mobile radio system access and control occurs over the con- trol channel. The control channel carries most of the control-related messages in the system includ- ing, but not limited to: origination requests, chan- nel assignments, power control, time alignment, sys- tem configuration, and system resource availability. The communication controller will respond to call requests received over the control channel with either a channel assigned message assigning the requesting

subscriber unit a channel for communication, or with a request queued message to the requesting mobile subscriber, queueing the request pending resource availability.

  The frequency at which a control channel oper- ates can be changed as the result of either an externally generated maintenance request or as the result of the base station detecting frequency inter- ference on the frequency used for the control chan- nel. The process ofmoving the control channel Tom one frequency to another is referred to as a control channel switch.

  Mobile subscribers that have queued calls are tuned to the frequency of the control channel. When a control channel switch occurs the mobile subscriber units with queued calls must be informed of the new frequency of the control channel. This enables the mobile subscribers units to receive a channel assignment message on the new control channel when resources become available to satisfy their queued request.

0 Motorola 1°C. 19% 160 November1996

[This page contains 15 pictures or other non-text objects]

Page 2 of 5

0 M M-LA

Technical Developments

M

CONTROLLER

MMZ

b

I

I II Mobile

Mobile ",u,scri ber

Subscriber Unit

Fig. 1 Wireless, Trunked Communication System

DESCRIPTION

  The communication controller will initiation a control channel switch process when it receives a command from a Man Machine Interface (MIvlI) terminal or an Operations and Maintenance Center (OMC) instructing the controller to change the he- quency ofthe control channel, or requesting the base station with the control channel be taken out of serv- ice. The control channel switch process may also be automatically initiated in response to the base sta- tion detecting frequency interference on the frequency used for the control channel....