Adaptive Differential Pulse Code Modulation Using PIC Microcontrollers

Adaptive Differential Pulse Code Modulation Using PICmicro Microcontrollers

In the past, adding speech recording and playback capability to a product meant using a digital signal processor or a specialized audio chip. Now, using a simplified Adaptive Differential Pulse Code Modulation (ADPCM) algorithm, these audio capabilities can be added to any PICmicro device. This application note will cover the ADPCM compression and decompression algorithms, performance compariso...

Speech Compression using ADPCM

We propose a simple speech compression algorithm using subband division and ADPCM (Adaptive Differential Pulse Code Modulation) algorithm. Although speech data are stored in a semiconductor memory device, its capacity and the available network capacity are limited. Therefore, it is necessary to compress the data as much as possible. The first is that the reconstructed datum must be understood c...

Toll Quality Voice - 32 kbit/s Adaptive Differential Pulse Code Modulation (ADPCM) MIME Sub-type Registration

Toll Quality Voice-32 kbit/s Adaptive Differential Pulse Code Modulation (ADPCM) MIME Sub-type Registration Status of this Memo This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "Internet Official Protocol Standards" (STD 1) for the standardization state an...

Quantization is the process of mapping a continuous range of amplitudes of a signal into a finite set of discrete amplitudes Uniform quantization Nonuniform quantization Adaptive quantization Vector quantization Adaptive Differential Pulse Code Modulation

CCK Encoding with PIC Based Microcontrollers for The Wireless Communications

The IEEE 802.11b is a Direct Sequence Spread Spectrum (DSSS) system very similar in concept to the CDMA Wireless, using a spread spectrum chip sequence. In the 802.11b the transmission medium is wireless and the operating frequency band is 2.4GHz. 802.11b provides 5.5 and 11 Mbps payload data rates in addition to the 1 and 2 Mbps rates provided by 802.11. To provide the higher rates, 8 chip Com...