  Ambient backscatter communication technology has been introduced recently,
and is then quickly becoming a promising choice for self-sustainable
communication systems as an external power supply or a dedicated carrier
emitter is not required. By leveraging existing RF signal resources, ambient
backscatter technology can support sustainable and independent communications
and consequently open up a whole new set of applications that facilitate
Internet-of-Things (IoT). In this article, we study an integration of ambient
backscatter with wireless powered communication networks (WPCNs). We first
present an overview of backscatter communication systems with an emphasis on
the emerging ambient backscatter technology. Then we propose a novel hybrid
transmitter design by combining the advantages of both ambient backscatter and
wireless powered communications. Furthermore, in the cognitive radio
environment, we introduce a multiple access scheme to coordinate the hybrid
data transmissions. The performance evaluation shows that the hybrid
transmitter outperforms traditional designs. In addition, we discuss some open
issues related to the ambient backscatter networking.
