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METHOD FOR CONSERVING ENERGY BY INTELLIGENTLY CYCLING FIXED END COMPONENTS IN A RADIO COMMUNICATION SYSTEM

IP.com Disclosure Number: IPCOM000009020D
Original Publication Date: 1999-Jan-01
Included in the Prior Art Database: 2002-Aug-01
Document File: 3 page(s) / 130K

Publishing Venue

Motorola

Related People

Jeffrey K. Jacobs: AUTHOR [+2]

Abstract

Trunked radio communication systems have dedicated RF channels for transmitting subscriber control information. Subscribers in such systems rely on the continuous availability of these control channels. In existing systems, then, stations acting as control channels must always have their transmit- ters keyed.

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MO7WROLA Technical Developments

METHOD FOR CONSERVING ENERGY BY INTELLIGENTLY CYCLING FIXED END COMPONENTS IN A RADIO COMMUNICATION SYSTEM

by Jeffrey K. Jacobs and Leslie G. Gustafson

INTRODUCTION

  Trunked radio communication systems have dedicated RF channels for transmitting subscriber control information. Subscribers in such systems rely on the continuous availability of these control channels. In existing systems, then, stations acting as control channels must always have their transmit- ters keyed.

  Some customers may need radio coverage over sparsely populated areas in which only a few, if any, subscribers exist at a given time. Control channels required to continuously broadcast their control information are inefficient for such applications. If there are no subscribers to receive the control infor- mation, little benefit is gained for the energy con- sumed.

  A method for cycling a control channel's trans- mitter to conserve energy is described below. This method takes the form of two algorithms. The algo- rithm performed by the stations acting as control channels is illustrated in Figure 1, and the algorithm performed by the subscribers is illustrated in Figure 2.

INVENTION

  Control channels capable of cycling their trans- mitters are described as sleeper control channels. A sleeper control channel when awake is transmitting its control information but when asleep has its trans- mitter dekeyed to conserve energy. Switching between these modes is completely driven by sub- scriber messaging.

  When in its energy conserving mode, the station monitors a Wake Up Frequency for subscriber Wake Up Request messages. This Wake Up Frequency is

a pre-determined frequency at which the subscriber can signal the sleeping control channel. A system may designate one system-wide Wake Up Frequency or choose to use a number of different frequencies for this purpose. Upon receiving a Wake Up Request message the station keys its trans- mitter and broadcasts its control information.

  Now awake, the station monitors subscriber affiliations. As long as subscribers are affiliated, it will remain awake. When the last subscriber deaf- filiates, or if no subscribers actually affiliate, the control channel will revert to its sleeping mode. In this way, a sleeper control channel only transmits control information when subscribers are present.

  Subscribers today have lists of control channe...