Semantic Communications for Speech Recognition
This work addresses bandwidth limitations for speech recognition applications by enabling more efficient transmission, though it is incremental as it builds on existing semantic communication concepts with a specific focus on speech.
The paper tackles the problem of inefficient data transmission in traditional communications by proposing DeepSC-SR, a semantic communication system for speech recognition that transmits only text-related semantic features, reducing data volume without performance loss and showing improved robustness in low SNR environments.
The traditional communications transmit all the source data represented by bits, regardless of the content of source and the semantic information required by the receiver. However, in some applications, the receiver only needs part of the source data that represents critical semantic information, which prompts to transmit the application-related information, especially when bandwidth resources are limited. In this paper, we consider a semantic communication system for speech recognition by designing the transceiver as an end-to-end (E2E) system. Particularly, a deep learning (DL)-enabled semantic communication system, named DeepSC-SR, is developed to learn and extract text-related semantic features at the transmitter, which motivates the system to transmit much less than the source speech data without performance degradation. Moreover, in order to facilitate the proposed DeepSC-SR for dynamic channel environments, we investigate a robust model to cope with various channel environments without requiring retraining. The simulation results demonstrate that our proposed DeepSC-SR outperforms the traditional communication systems in terms of the speech recognition metrics, such as character-error-rate and word-error-rate, and is more robust to channel variations, especially in the low signal-to-noise (SNR) regime.