The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 08, 1998
Filed:
Nov. 03, 1997
Robert W Furtaw, Lake Zurich, IL (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A cellular system (FIG. 4) is expanded to allow communication between mobile ground-based units (70 and 72) and mobile air-based units (80 and 78) where the air base units (e.g., a unit in airplane 78) operate above a threshold elevation. Mobile units below the threshold elevation level use local conventional cellular service area and cells whereas mobile units above the threshold are transferred to a frequency reuse pattern having a higher altitude of service and a larger service surface area. Switching between the air cells (41a-41g) and the land cells (26) is performed by determining if two land cell controllers operate at a same frequency both are receiving transmission from the mobile unit. If two land cells of the same frequency receive the same mobile unit transmission, then the mobile unit is above the threshold elevation and assigned to an air cell, else a land cell is used.