Title:
複雑さが軽減された信号送信システム
Document Type and Number:
Japanese Patent JP3970327
Kind Code:
B2
Abstract:
In a CELP coder a comparison between a target signal and a plurality of synthetic signals is made. The synthetic signal is derived by filtering a plurality of excitation sequences from a one dimensional codebook by a synthesis filter having parameters derived from the target signal. The excitation signal which results in a minimum error between the target signal and the synthetic signal is selected. In order to reduce the complexity of the search for the best excitation signal, the selection is done in two stages. First a preselection of a small number of excitation sequences is made by selecting only every Lth codebook entry for preselecting a plurality of excitation sequences. Thereafter, with this small number of excitation sequences, a full complexity search is made in which all excitation sequences surrounding the preselected ones are involved in the selection.
Inventors:
Upperman Fried Helm
Devont Franciscus Marinus Josephus
Devont Franciscus Marinus Josephus
Application Number:
JP52914097A
Publication Date:
September 05, 2007
Filing Date:
January 31, 1997
Export Citation:
Assignee:
Konin Krekka Philips Electronics NV
International Classes:
H04B1/62; G10L19/12; H03M7/30
Domestic Patent References:
| JP60162300A | ||||
| JP60235200A |
Foreign References:
| US4944013 |
Attorney, Agent or Firm:
Susumu Tsugaru
Masao Sawada
Masao Sawada