Multi-channel Wireless Audio System Using Adaptive Frequency-hopping
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing digital wireless audio systems face challenges in achieving high quality of service (QoS) and frequency diversity comparable to pro audio systems while using digital, frequency-agile radios, without requiring multiple radios at each system node, and maintaining low latency and cost constraints.
Innovation Solution
A multi-channel digital wireless audio system with a single transmit node and multiple receive nodes, utilizing a single radio transceiver on each node, incorporating hardware-multithreaded processors for baseband, protocol, and audio processing functions, and implementing adaptive frequency-hopping techniques to achieve high QoS and reduce system size and power consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If multiple radios are used at each system node to achieve high QoS and frequency diversity, then reliability is improved, but device complexity and cost increase
Solution Approach 1:
The system dynamically switches between different frequency channels using frequency-hopping spread spectrum (FHSS) technology. Instead of using multiple static radios, a single radio dynamically transitions through multiple frequencies according to a pseudorandom sequence, achieving frequency diversity and avoiding interference without requiring multiple radio hardware units at each node
Solution Approach 2:
The system changes the operating frequency parameter over time according to a predetermined hopping sequence. The radio frequency is dynamically adjusted between different channels (e.g., 2.402 GHz to 2.480 GHz) to avoid interference and maintain reliable communication, replacing the need for multiple fixed-frequency radios
2Use of energy by moving object
If narrow-band radios are used to reduce system size and power consumption, then device complexity and energy use are reduced, but the ability to achieve high QoS and frequency diversity is worsened
Solution Approach 1:
The narrow-band radio is made dynamic through frequency-hopping operation. Although the radio itself is narrow-band, it achieves frequency diversity by rapidly switching between multiple narrow-band channels according to an FHSS sequence, maintaining reliability while keeping the radio hardware simple and power-efficient
Solution Approach 2:
The frequency spectrum is segmented into multiple narrow-band channels (e.g., 8 channels from 2.402 GHz to 2.480 GHz). The system divides the communication task across these segments by hopping between them, achieving the benefits of frequency diversity through segmentation rather than through parallel wide-band radios
3Productivity
If audio compression techniques are used to reduce data rate, then productivity is improved, but manufacturing precision of audio quality is worsened
Solution Approach 1:
The system applies partial compression using ADPCM (Adaptive Differential Pulse Code Modulation) that preserves the most critical audio information while reducing data rate. By using adaptive quantization and differential encoding, the system achieves compression without excessively degrading audio quality, finding an optimal balance between productivity and quality
Data Source
AI summary
In a multi-channel digital wireless audio system with at least one transmit node and at least one receive node, each node can both receive and transmit digital audio signals. Signals sent from a receive node to a transmit node may acknowledge satisfactory signal receipt, or may requesting retransmission of data packets received in a corrupted state. Original and retransmitted signals may be sent in compressed form to enable use of narrow-band digital radios. The system preferably incorporates a dual control channel to enable transmission of meta data. Each system node preferably incorporates a hardware-multithreaded processor adapted to implement various functions such as baseband functions, RF protocol functions, error correction functions, and audio processing functions, with each independent thread being adapted to implement a different functional block.