Gain controller with automatic adjustment using integration energy values
AssigneeNEC Corporation
InventorsToshio Yoshida, Mititaka Sisido
Life of this patent
Estimating the term…
Abstract
A gain controller for use in mobile telephone system is disclosed. It is judged whether digital input data includes speech data or not. When the digital input data includes speech data, an integration energy value of the digital speech data for a predetermined time length is measured. The measured integration energy value is compared with a higher threshold value and a lower threshold value. A step level is set to a predetermined minus value, a predetermined plus value and "0" when the integration energy value is higher than the higher threshold value, lower than the lower threshold value and within a range between the higher and lower threshold values, respectively. The obtained step level is then added to the digital speech data.
Claims4
A gain controller comprising:
- judging means for Judging whether digital input data includes speech data or not;
- measuring means, when the digital input data includes speech data, for measuring an integration energy value of the digital speech data for a predetermined time length;
- comparison means for comparing the measured integration energy value with a higher threshold value and a lower threshold value;
- setting means for setting a step level to a predetermined minus value, a predetermined plus value and "0" when the integration energy value is higher than the higher threshold value, lower than the lower threshold value and within a range between the higher and lower threshold values, respectively;
- and
- adding means for adding the step level to the digital speech data.
A gain controller comprising:
- antenna means for receiving a radio modulated digital data comprising speech delta and control data for a predetermined time length;
- a radio unit means for decoding the signal supplied from said antenna means and producing the modulated digital data;
- a channel decoder means for separating the digital data from said radio unit means into speech data and control data;
- judging means for judging whether digital input data includes speech data or not;
- measuring means, when the digital input data includes speech data, for measuring an integration energy value of the digital speech data for a predetermined time length;
- comparison means for comparing the measured integration energy value with a higher threshold value and a lower threshold value;
- setting means for setting a step level to a predetermined minus value, a predetermined plus value and "0" when the integration energy value is higher than the higher threshold value, lower than the lower threshold value and within a range between the higher and lower threshold values, respectively;
- adding means for adding the step level to the digital speech data;
- D/A converter means for converting the speech data from said adding means into an analog speech signal;
- amplifying means for amplifying the analog speech signal;
- and
- speech reproducing means for reproducing speech sound based upon the amplified speech signal.
Dependencies are inferred from the claim text.