Wireless communication system, weight control apparatus, and weight vector generation method

Abstract

Signals received by a plurality of antenna elements are supplied to a beam forming circuit via a distributor. The beam forming circuit weights and combines the signals to output a reception signal corresponding to a beam having a predetermined directionality pattern. A weight used to control weighting and combining is set by a weight controller. Upon receiving a registration request from an unregistered terminal, the weight controller calculates a weight vector used to form a beam having null directionality toward that terminal, and maximum directionality toward the range of an area other than an area where the terminal is located of a plurality of areas obtained by dividing the area covered by the antenna elements in accordance with direction.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2000-333202, filed Oct. 31, 2000, the entire contents of which are incorporated herein by reference. BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] The present invention relates to a wireless communication system for making space-division multiple access, a weight control apparatus, and a weight vector generation method. [0004] 2. Description of the Related Art [0005] In an FWA (Fixed Wireless Access) system, a base station and fixed terminal station make wireless, high-speed communications. In a point-to-multipoint (P-MP) system, a base station communicates with a plurality of terminal stations. In the P-MP system, space-division multiplex access (SDMA) is known as means for increasing the subscriber capacity. As shown in FIG. 16, an adaptive array 1002 arranged in a base station 1001 forms orthogonal be...

AI Technical Summary

Benefits of technology

"The present invention provides a wireless communication system, weight control apparatus, and weight vector generation method that can prevent the number of weights to be held from increasing abruptly even when the number of terminals increases, by not preparing orthogonal beams in correspondence with combinations of terminals upon space-division multiplex access. Additionally, the invention reduces the apparatus scale by limiting the number of interference waves to be suppressed in a wireless communication system that makes packet communications using CSMA / CA, and forms beams that remove these interference waves. The invention also allows simultaneous communications with a plurality of terminals by space-division multiplex access, by using a plurality of antenna elements, beam forming units, and a controller to set weight vectors used to control weighting and combining in the beam forming units. The controller calculates and stores at least one of the weight vectors used to form a beam having null directionality toward the unregistered terminal and maximum directionality toward a specific area other than an area where the unregistered terminal is located of areas obtained by dividing a cover area covered by the wireless communication system."

Problems solved by technology

However, in order to suppress all co-channel interference waves from a neighboring cell, the number of antenna elements must be increased, resulting in a large apparatus scale.

Since the IEEE802.11 wireless LAN system using CSMA / CA does not make integrated control of packet transmission, as described above, it is difficult to form a situation in which only terminals or base stations to be suppressed transmit packets.

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