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Quantization noise in digital speech. m.s. thesis- houston univ.
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Schmidt, O. L. |
| Copyright Year | 1972 |
| Description | The amount of quantization noise generated in a digital-to-analog converter is dependent on the number of bits or quantization levels used to digitize the analog signal in the analog-to-digital converter. The minimum number of quantization levels and the minimum sample rate were derived for a digital voice channel. A sample rate of 6000 samples per second and lowpass filters with a 3 db cutoff of 2400 Hz are required for 100 percent sentence intelligibility. Consonant sounds are the first speech components to be degraded by quantization noise. A compression amplifier can be used to increase the weighting of the consonant sound amplitudes in the analog-to-digital converter. An expansion network must be installed at the output of the digital-to-analog converter to restore the original weighting of the consonant sounds. This technique results in 100 percent sentence intelligibility for a sample rate of 5000 samples per second, eight quantization levels, and lowpass filters with a 3 db cutoff of 2000 Hz. |
| File Size | 2513998 |
| Page Count | 66 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19720022541 |
| Archival Resource Key | ark:/13960/t7bs3jq79 |
| Language | English |
| Publisher Date | 1972-08-01 |
| Access Restriction | Open |
| Subject Keyword | Speech Intelligibility Consonants Speech Electromagnetic Noise Digital To Analog Converters Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Thesis |
