Title
FreeScatter: Enabling Concurrent Backscatter Communication Using Antenna Arrays
Abstract
The design paradigm for backscatter tags is to avoid complex functionality and make tags as simple as possible. However, such a design principle leads to the prevalence of signal collision as tags cannot sense other tags' ongoing transmissions. The high probability of tag collision will result in low overall throughput. Although there are some existing efforts to resolve tag collisions, they either require good channel conditions or can only resolve a limited number of tags as channel capacity is deficient when SNR is low. In this article, to overcome this limitation, we bring in antenna arrays to boost the channel capacity. We propose FreeScatter, which can support scalable concurrent backscatter transmission using an antenna array. FreeScatter extracts the path that signals traveled and formulates the tags' channel coefficient using the path representations. FreeScatter further exploits the frequency agnostic property so that it can support more spatial streams than the number of antennas. The experimental results show that we can enable up to 20 tags transmitting concurrently. With the ubiquitous connectivity of battery-free tags in the near future, FreeScatter can significantly boost the network throughput.
Year
DOI
Venue
2020
10.1109/JIOT.2020.2984877
IEEE Internet of Things Journal
Keywords
DocType
Volume
Antenna arrays,array signal processing,backscatter,parallel communication
Journal
7
Issue
ISSN
Citations 
8
2327-4662
0
PageRank 
References 
Authors
0.34
0
6
Name
Order
Citations
PageRank
Qianyi Huang110.69
Guochao Song201.69
Wei Wang 0050327436.01
Huixin Dong401.01
Zhang Jin544.45
Qian Zhang65483343.05