Wireless Communication Device ADPCM Error Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Wireless communication systems face challenges in maintaining sound quality when the communication environment deteriorates, as they often reduce data rates and increase error correction bits, leading to degraded sound quality.
Innovation Solution
A wireless communication device and system that convert part of the digital sound data into error detection bits, allowing for accurate error detection while maintaining sound data rates, using adaptive differential pulse code modulation (ADPCM) and error detection mechanisms to adapt to changing communication environments.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the data amount of error correction bits is increased to cope with deteriorated communication environment, then the tolerance to interference radio wave is improved, but the data rate of sound data is reduced leading to sound quality deterioration
Solution Approach 1:
The patent segments the fixed-size packet into distinct regions: sound data samples and error correction bits. By monitoring the error rate in received packets, the system dynamically adjusts the allocation ratio between these two segments. When error rate is low, more bits are allocated to sound data (higher productivity); when error rate is high, more bits are allocated to error correction (higher reliability). This segmentation allows independent optimization of both competing objectives.
Solution Approach 2:
The patent implements dynamic switching between different packet construction modes based on monitored error rate conditions. The system transitions from a static fixed allocation to a dynamic adaptive allocation where the ratio of sound data samples to error correction bits changes in response to communication environment quality. This dynamics enables the system to optimize the trade-off between reliability and productivity according to real-time conditions.
2Length of stationary object
If the data amount of error correction bits is increased to widen distance range, then the coverage is improved, but the data rate of sound data is reduced leading to sound quality deterioration
Solution Approach 1:
The patent segments the fixed-size packet into distinct regions: sound data samples and error correction bits. By monitoring the error rate in received packets, the system dynamically adjusts the allocation ratio between these two segments. When error rate is low, more bits are allocated to sound data (higher productivity); when error rate is high, more bits are allocated to error correction (higher reliability). This segmentation allows independent optimization of both competing objectives.
Solution Approach 2:
The patent implements dynamic switching between different packet construction modes based on monitored error rate conditions. The system transitions from a static fixed allocation to a dynamic adaptive allocation where the ratio of sound data samples to error correction bits changes in response to communication environment quality. This dynamics enables the system to optimize the trade-off between reliability and productivity according to real-time conditions.
3Measurement precision
If error detection and correction coding is performed on digital sound data, then the accuracy of error detection is improved, but the data rate of sound data is reduced leading to sound quality deterioration
Solution Approach 1:
The patent segments the fixed-size packet into distinct regions: sound data samples and error correction bits. By monitoring the error rate in received packets, the system dynamically adjusts the allocation ratio between these two segments. When error rate is low, more bits are allocated to sound data (higher productivity); when error rate is high, more bits are allocated to error correction (higher reliability). This segmentation allows independent optimization of both competing objectives.
Solution Approach 2:
The patent changes the parameter of error correction bit allocation dynamically based on monitored error rate conditions. The system adjusts the number of error correction bits as a variable parameter rather than using a fixed value, enabling optimization of the trade-off between error detection accuracy and sound data rate according to actual communication environment quality.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The present invention provides a wireless communication device and a wireless communication system which can improve the error detection accuracy with the sound quality maintained to some extent even if the communication environment is deteriorated. A cordless phone establishes a digital link on a wireless channel between a master device and a slave device, compresses a sound signal in an ADPCM scheme, and carries the sound signal in a sound packet to perform communication. In a master device side, a PCM signal is converted into ADPCM data by an ADPCM encoding unit. Next, the least significant bit of n-bits is set according to the number of "1" of the n-bits of the ADPCM data by a transmission conversion table. In a slave device side, it is determined whether an error has occurred according to the number of "1" of the n-bit data in received data. If the error exists, the n-bit sound data is converted into mute data through a reception conversion table. The sound data converted through the reception conversion table is converted into a PCM signal from an ADPCM format by an ADPCM decoding unit.