Toward Full Passive Internet of Things: Symbiotic Localization and Ambient Backscatter Communication

Abstract

In this paper, we proposed a symbiotic localization and ambient backscatter communication (SLABC) architecture, which uses existing ambient backscatter communication (AmBC) hardware and received signals to help Internet of Things (IoT) localize target objects. The SLABC can be viewed as a specific realization of integrated passive/symbiotic sensing and communication, which has two mutually beneficial stages: 1) sensing stage with generalized Prony with homologous matching (GPHM) method; 2) communication stage with multi-source constant modulus algorithm (MSCMA) method. To formulate SLABC, we propose a unified TMSC signal model to characterize the complex multi-source, multi-path and multi-reflection symbiotic communication (TMSC) and facilitate the key information extraction. Utilizing the frequency domain expression of the unified signal model and the similarity between multi-path channel coefficients and tap coefficients of equalizers, our proposed GPHM and MSCMA methods are efficient to mitigate the TMSC interference and retrieve the interested information to locate targets and communicate. The proposed SLABC concept updates the symbiotic AmBC IoT with the least cost and reduces the dependence on hardware stacking. The simulation results show that: 1) information extracted by GPHM and MSCMA can help localization achieve high accuracy and reduce the complexity of multi-path interference mitigation; 2) both of the two methods have a positive influence on each other.