Revisiting Wi-Fi Performance under the Impact of Corrupted Channel State Information
Youngwook Son, Saewoong Bahk · 2020
Wi-Fi devices become increasingly susceptible to mutual interference in congested network scenarios. If a device starts to receive a new frame in the presence of concurrent interference signal, its preamble reception can be seriously damaged, which spoils the channel estimation process. The resulting corrupted channel state information (CSI) causes persistent decoding errors throughout the data payload. This paper presents a comprehensive study into the impact of corrupted CSI on Wi-Fi performance. Through experimental study and link-level analysis, we verify that actual receiver performance is highly dependent on CSI acquisition at the preamble, which has never been reflected by any physical layer abstraction models. We develop a realistic model that reflects the impact of corrupted CSI on overall frame reception. Applying our model to ns-3 simulator, we revisit network performance in interference-prone scenarios, to assess consistency with real-world Wi-Fi systems.