Browse Prior Art Database

METHOD FOR BEAMS LAYDOWN IN POWER-CONSTRAINED SATELLITE COMMUNICATION SYSTEMS

IP.com Disclosure Number: IPCOM000008889D
Original Publication Date: 1998-Sep-01
Included in the Prior Art Database: 2002-Jul-22
Document File: 2 page(s) / 101K

Publishing Venue

Motorola

Related People

Vih Guang Jan: AUTHOR

Abstract

In satellite cellular communication systems, beam activation schedules need to be managed in a systematic manner to ensure a proper balance between system capacity, communication quality, and power consumption. However, the following phenomena or problems are encountered when designing beam management algorithms: I) A snapshot of beam activation schedules is designed: Because of this snapshot schedule beams to be activated at one time are independent from other times thus making it very difficult to allocate communication channels to handle call handoff processes.

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MOlOROLA Technical Developments

METHOD FOR BEAMS LAYDOWN IN POWER-CONSTRAINED SATELLITE COMMUNICATION SYSTEMS

by Vih Guang Jan

  In satellite cellular communication systems, beam activation schedules need to be managed in a systematic manner to ensure a proper balance between system capacity, communication quality, and power consumption. However, the following phenomena or problems are encountered when designing beam management algorithms:

  I) A snapshot of beam activation schedules is designed: Because of this snapshot schedule beams to be activated at one time are independent from other times thus making it very difficult to allocate communication channels to handle call handoff processes.

  2) The existence of isolated activated beams: Because isolated activated beams exist, calls in these beams will be dropped when they need to be handed over to other beams when environment situ- ation changes.

  3) Short-lives of activated beams: Because acti- vated beams have relatively short lives, the calls handoff rate increases and consequently the possi- bility of those calls being dropped increases.

  4) Difference in the number of beams being acti- vated in orbital planes: Because the number of beams being activated in every orbital plane has wide range of difference it becomes difficult to effectively control or manipulate the power con- sumption in all antenna panels.

  5) The maximum potential number of active beams is not contemplated in the design process: When too many beams are activated it will be virtu- ally impossible for the system to generate enough power to support this requirement. On the other hand if it has less than required activated beams,

the system will not be able to cover all its serving areas and the system capacity will be dropped accordingly.

  6) Non-uniform beams coverage: Beams tend to converge upon each other more intensely when satellites are moving toward high latitude areas, consequently beams coverage in the high and low latitude levels are not uniform and this can result in a non-uniform system performance.

  A new beams Iaydown method has been devel- oped. This method design will correct the identified problems and/or implementation dif...