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:
May. 03, 2005
Filed:
Apr. 30, 2001
Akira Shibutani, Sunnyvale, CA (US);
Akira Shibutani, Sunnyvale, CA (US);
NTT DoCoMo, Inc., Tokyo, JP;
Abstract
The present invention provides a transmission control scheme for wireless digital networks comprised of a plurality of access points each communicating with access terminals, which improves data throughput to access terminals located in areas where interference from the neighboring access points are high. Generally, under the transmission control scheme according to the present invention, the access points are controlled so that neighboring access points will not transmit signals simultaneously with transmission parameters providing high robustness. The transmission parameters include, for instance, transmission power, a modulation scheme and a coding rate. Higher power transmission achieves higher robustness. Transmission at a lower modulation level achieves higher robustness. Transmission at a lower coding rate achieves higher robustness. Transmission providing high or low robustness will expand or narrow a virtual communication zone, which is defined in this application as an area within which it is feasible at a given level of error performance for access terminals to communicate with the access point in the zone. The access points may change their transmission parameters according to predetermined schedules, such as at regular intervals.