Spectro-Temporal Combining in Bistate WiFi Backscatter Communication With Frequency Shift

In WiFi backscatter communication, the frequency shift technique allows a backscattered signal to appear not in channel of carrier but adjacent ones, thus avoiding noisy OFDM-based signals and increasing communication range. Through testbed experiments, we observe that is effective mitigating impact inherent fluctuation signals, particularly bistate communication; however, due weak strength signal, other from incumbent transmitters may shifted channels, significantly interfering with signal. To combat this challenge way nondisruptive transmitters, propose receiver-side spectro-temporal combining scheme which spectrum performed suppress interference appearing one while temporal transmission repetitions bit errors resulting residual interference. The scheme’s on-the-fly bit-sequence require minimal buffer memory. system prototyping demonstrate proposed outperforms conventional temporal-combining-only cases terms error rate throughput under various conditions.