喷泉码纠错的无线网络切片传输时间分析

Transmission time analysis of wireless network slicing based on fountain codes

摘要:

为了提高无线通信中网络切片传输的吞吐率，避免引入大量的反馈延时，将无重传的喷泉码机制用于无线网络切片的纠错传输.在该方案中，采用基于喷泉码的前向纠错机制代替传统的自动重传请求机制，实现网络切片的无线传输；并针对喷泉码纠错机制，优化了网络切片的切片方案.这种方案，通过喷泉码无重传以及低冗余度的纠错特性，可以降低网络切片传输协议的复杂度和传输延时；尤其在丢包率较大的网络环境下，单位时间内喷泉码方案可以传输更多的有效切片数据，提高无线网络切片的传输吞吐率.在此基础上，分别构建了基于喷泉码的无线网络切片传输系统和基于自动重传请求方案的无线网络切片传输系统，并对这两个系统的传输时间进行了分析和比较.仿真结果表明：当网络丢包率超过5×10^-2时，网络切片采用喷泉码方案具有比自动重传请求方案更低的传输时间；当丢包率为10^-1时，喷泉码方案的传输时间比自动重传请求方案可降低22%以上；随着丢包率的增大，喷泉码方案在传输时间上的优势更加明显.

Abstract:

To increase the throughput and reduce the feedback latency of wireless network slicing transmission, an error correction scheme based on no-retransmission fountain codes was proposed. The scheme used fountain codes to replace the traditionally automatic retransmission request (ARQ) in network slicing transmission. An improved slicing method for the error correction scheme was also given. Because of its no-retransmission and small redundancy, this scheme can provide reduced complexity and transmission latency for network slicing transmission at the same time. Moreover, it can provide raised throughput when packet loss probability is increased, thus it gives a high efficient network slicing transmission scheme. Analysis and simulation were given for the fountain code-based transmission and the ARQ-based transmission. Simulation showed the transmission latency with fountain codes was lower than that with ARQ when the packet loss probability was beyond 5×10^-2. With the increase of packet loss probability in wireless network, the advantage was more evident and the latency could reduce up to 22% when loss probability was 10^-1.