Title :
A study of transfer function estimation error and a practical multibeam antenna system with precoding interference cancellation
Author_Institution :
NTT DoCoMo Inc., Kanagawa, Japan
Abstract :
Beyond IMT-2000, systems must use high ability interference canceling technology to achieve high speed and high capacity transmission. This paper proposes a kind of precoding technology that, in a practical manner, can completely cancel downlink interference in the same space and the same frequency band. The concept of this technology is to multiply the transmitting signal by the inverse matrix of the space transfer functions matrix sent by each mobile station. Its high interference cancellation performance is evaluated by considering the error in estimating the transfer function. A new scheme is proposed that is extremely practical because it eliminates the need to measure the delay. A fully implemented system is described.
Keywords :
antenna radiation patterns; cellular radio; encoding; interference suppression; matrix inversion; matrix multiplication; multibeam antennas; parameter estimation; radiofrequency interference; transfer function matrices; IMT-2000; antenna patterns; delay; downlink interference; high capacity transmission; high speed transmission; interference cancellation; inverse matrix; multibeam antenna system; precoding technology; transfer function estimation error; Antenna measurements; Antenna theory; Base stations; Estimation error; Frequency measurement; Interference cancellation; Mobile antennas; Space technology; Transfer functions; Transmitting antennas;
Conference_Titel :
Antennas and Propagation Society International Symposium, 2001. IEEE
Conference_Location :
Boston, MA, USA
Print_ISBN :
0-7803-7070-8
DOI :
10.1109/APS.2001.959386
