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:
Oct. 01, 2013
Filed:
Oct. 28, 2009
Yongcai Wang, Beijing, CN;
Junhui Zhao, Beijing, CN;
Yongcai Wang, Beijing, CN;
Junhui Zhao, Beijing, CN;
NEC (China) Co., Ltd., Beijing, CN;
Abstract
The present invention provides a multi-objects positioning system and power-control based multiple access control method. The multi-objects positioning system according to the present invention comprises a plurality of tag devices carried by multiple objects and one or more positioning devices for determining the positions of the objects, wherein each of the tag devices includes a positioning device list for recording status information of the positioning devices. According to the present invention, tag device broadcasts Channel Request Packet (CRP) intermittently; positioning device, which is idle and receives the CRP, broadcasts Channel Allocation Packet (CAP) in its coverage range to allocate a channel to the tag device that is the sender of the CRP and inform information of the positioning device to other tag devices; tag device, which receives the CAP, updates its positioning device list according to the contents of the CAP; and the tag device adjusts transmission power of the CRP by referring to the positioning device list. With the present invention, the EN and HN problems existing in the prior arts can be solved effectively, and it is helpful to solve signal collision and improve spatio-temporal reuse capacity of the system.