This paper presents a robust and adaptable framework integrating diverse wireless communication technologies for next-generation emergency communications. We designed a real-time voice streaming system that enables reliable voice and data transmission over low-bitrate links. The system incorporates flow control and queuing mechanisms to ensure seamless interoperability of Internet Protocol (IP)-based low-bitrate voice communication across Long Range (LoRa), Direct Sequence Spread Spectrum (DSSS), and Wi-Fi networks. This approach facilitates efficient cross-network communication, which is vital for emergency scenarios. The performance evaluation of the system involved assessing the system’s ability to transmit low-bitrate voice using a novel voice-over low-bitrate protocol. Key metrics such as packet latency, inter-arrival time, and jitter were measured to investigate the system’s reliability in streaming low-bitrate voice. Our results confirm that the system supports low-bitrate voice transmission over channels with data rates below 1 kbps. When data streams from high to moderate bit-rate channels, controlling the flow of packets is essential for reliable communication as this enables the high-rate channels to adapt to the rate of low-bit-rate channels. Additionally, managing packet flow from high- to low-bitrate streams is critical for consistent communication, enabling higher-rate channels to adjust dynamically to low-bitrate conditions. Selecting optimal packet sizes to maximize channel utilization minimizes latency and combined with queuing strategies, ensures dependable delivery. These findings establish a foundation for leveraging low-bitrate satellite and Low Power Wide Area Networks (LPWAN) to develop resilient and scalable emergency communication systems for next-generation applications.