Back to results
US 6,188,346 B1Granted
Analog-to-digital conversion device
AssigneeNippon Telegraph and Telephone Corporation
InventorsTakao Waho, Toshihiro Itoh
Life of this patent
Estimating the term…
Abstract
An analog-to-digital conversion device includes quantization circuits and binarization circuits. Each quantization circuit samples an input analog signal at a predetermined period to obtain a sample, quantizes the sample into a (n+1)-valued signal with n (n is an integer of two or more) thresholds, and outputs the quantized value. Each binarization circuit converts the (n+1)-valued quantized value output from the quantization circuit into a binary code.
Claims15
An analog-to-digital conversion device comprising:
- quantization means for sampling an input analog signal at a predetermined period to obtain a sample, quantizing the sample into a (n+1)-valued signal with n (n is an integer not less than two) thresholds, and outputting the quantized value;
- binarization means for converting the (n+1)-valued quantized value output from said quantization means into a binary code;
- least significant bit quantization means, having 2m/n (m is an integer not less than two) conversion means each including said quantization means and said binarization means, for generating a least significant bit;
- (m−2) intermediate bit quantization means having said conversion means half the number of conversion means of bit quantization means for generating a bit one bit lower than itself;
- and
- most significant bit quantization means, having one said conversion means, for generating a most significant bit,
- wherein said least significant bit quantization means and said intermediate bit quantization means respectively include output means each for calculating an OR of outputs from said conversion means,
- each of said conversion means of said least significant bit quantization means, said intermediate bit quantization means, and said most significant bit quantization means has n thresholds having a difference larger than that in said quantization means for a bit one bit lower than itself, and
- each of said conversion means of said least significant bit quantization means, said intermediate bit quantization means, and said most significant bit quantization means has n different thresholds.
6 more elements
An analog-to-digital conversion device comprising:
- coarse quantization means for sampling an input analog signal at a predetermined period to obtain a sample, quantizing the sample into a (n+1)-valued signal with n coarse thresholds, and outputting the coarsely quantized value;
- n+1 fine quantization means each for sampling the analog signal at a predetermined period to obtain a sample, quantizing the sample into a (n+1)-valued signal with n fine thresholds between two adjacent coarse thresholds of the coarse thresholds in said coarse quantization means, and outputting the finely quantized value;
- signal selection means for selecting the finely quantized value output from said fine quantization means which has a threshold between the two thresholds used to quantize the (n+1)-valued coarsely quantized value output from said coarse quantization means;
- first binarization means for converting the (n+1)-valued coarsely quantized value output from said coarse quantization means into a binary code;
- and
- second binarization means for converting the finely quantized value selected by said signal selection means into a binary code.
3 more elements
An analog-to-digital conversion device comprising:
- coarse quantization means for sampling an input analogisignal at a predetermined period to obtain a sample, quantizing the sample with n coarse thresholds, and outputting the coarsely quantized value;
- n+1 fine quantization means each for sampling the analog signal at a predetermined period to obtain a sample, quantizing the sample with n (n is an integer not less than two) fine thresholds between two adjacent coarse thresholds of the coarse thresholds in said coarse quantization means, and outputting the finely quantized value;
- coarse binarization means for converting the coarsely quantized value output from said coarse quantization means into a binary code;
- n fine binarization means for converting the finely quantized values output from said fine quantization means into binary codes;
- first bit selection means for selecting one of bit values obtained by said fine binarization means by converting the finely quantized value output from said fine quantization means which has a threshold between the two thresholds used to quantize the coarsely quantized value output from said coarse quantization means;
- and
- second bit selection means for selecting the other of the bit values obtained by said fine binarization means by converting the finely quantized value output from said fine quantization means which has a threshold between the two thresholds used to quantize the coarsely quantized value output from said coarse quantization means.
4 more elements
An analog-to-digital conversion device comprising:
- quantization means for sampling an input analog signal at a predetermined period to obtain a sample, quantizing the sample into a (n+1)-valued signal with n (n is an integer not less than two) thresholds, and outputting the quantized value;
- binarization means for converting the (n+1)-valued quantized value output from said quantization means into a binary code;
- first conversion means, constituted by said quantization means in which n is set to 3 and said binarization means, for outputting a most significant bit and a first intermediate bit one bit lower than the least significant bit;
- second to fifth conversion means, constituted by said quantization means in which n is set to 3 and said binarization means, for outputting first and second binary codes;
- first output means for outputting a second intermediate bit one bit lower than the first intermediate bit using a combination of first binary codes output from said second to fifth conversion means;
- and
- second output means for outputting a least significant bit using a combination of second binary codes output from said second to fifth conversion means,
- wherein said binarization means outputs a binary value, as a first binary code, which is binarized between a largest value or a second largest value of four values output from said quantization means and other values thereof, and outputs a binary value as a second binary code, which is binarized between a largest value or a smallest value of four values output from said quantization means and in other values thereof,
- three thresholds in a quantization circuit of said second conversion means are smaller than a minimum threshold in a quantization circuit of said first conversion means,
- three thresholds in a quantization circuit of said third conversion means are larger than the minimum threshold in a quantization circuit of said first conversion means and smaller than an intermediate threshold in the quantization circuit of said first conversion means,
- three thresholds in a quantization circuit of said fourth conversion means are larger than the intermediate threshold in the quantization circuit of said first conversion means and smaller than a maximum threshold in the quantization circuit of said first conversion means, and
- three thresholds in a quantization circuit of said fifth conversion means are larger than the maximum threshold in the quantization circuit of said first conversion means.
9 more elements
Dependencies are inferred from the claim text.