Title:
METHOD AND DEVICE FOR IDENTIFYING SYSTEM
Document Type and Number:
Japanese Patent JP3631668
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide a method and device for identifying system by which the characteristics of an unknown system which makes the convergence of an adaptive filter maintainable even when a disturbance is added due to the voice of a near-end speaker having power which is smaller than such an echo that is not able to be detected by means of a double talk detector.
SOLUTION: The device for identifying system is provided with a background noise level estimating circuit 106 and a near-end voice level estimating circuit 107 as noise power estimating means, and uses the means for the decision of the step size 105 decided by a step size deciding circuit 104 for correcting the filter factor of the adaptive filter 101. The near-end voice level estimating circuit 107 executes such operation that follows the temporal fluctuation of an error signal 4 at a high speed by utilizing such a feature that the temporal fluctuation of voice power is large as compared with that of background noise power. The convergence of the adaptive film 101 is maintained by making the step size 105 smaller according to the noise power.
Inventors:
Morishita Yasumasa
Application Number:
JP2000255710A
Publication Date:
March 23, 2005
Filing Date:
August 25, 2000
Export Citation:
Assignee:
NEC Engineering Co., Ltd.
International Classes:
H03H21/00; H04B3/23; (IPC1-7): H04B3/23
Domestic Patent References:
| JP8130495A | ||||
| JP7202765A | ||||
| JP4271622A | ||||
| JP2265332A | ||||
| JP4081133A | ||||
| JP7131389A | ||||
| JP6013940A | ||||
| JP8288894A | ||||
| JP10322441A | ||||
| JP8293820A | ||||
| JP61072419A | ||||
| JP11513553A |
Other References:
平野 晃宏, 杉山 昭彦,“参照信号パワーと雑音パワーに基づく可変ステップサイズ確率勾配アルゴリズム”,1994年電子情報通信学会秋季大会講演論文集 基礎・境界,1994年 9月 5日,p.115,(A-115)
Attorney, Agent or Firm:
Masahiro Fukuyama