Title
Hybrid Beamformer Design For High Dynamic Range Ambient Backscatter Receivers
Abstract
In bi-static Ambient Backscatter Communications (AmBC) systems, the receiver needs to operate at a large dynamic range because the direct path from the ambient source to the receiver can be several orders of magnitude stronger than the scattered path modulated by the AmBC device. In this paper, we propose a novel analog-digital hybrid null-steering beamformer which allows the backscatter receiver to detect and decode the weak AmBC-modulated signal buried in the strong direct path signals and the noise, without requiring the instantaneous channel state information. The analog cancellation of the strong signal components allows the receiver automatic gain control to adjust to the level of the weak AmBC signals. This hence allows common analog-to-digital converters to be used for sampling the signal. After cancelling the strong components, the ambient source signal appears as zero mean fast fading from the AmBC system point of view. We use the direct path signal component to track the phase of the unknown ambient signal. In order to avoid channel estimation, we propose AmBC to use orthogonal channelization codes. The results show that the design allows the AmBC receiver to detect the backscatter binary phase shift keying signals without decoding the ambient signals and requiring knowledge of the instantaneous channel state information.
Year
DOI
Venue
2019
10.1109/iccw.2019.8757120
2019 IEEE INTERNATIONAL CONFERENCE ON COMMUNICATIONS WORKSHOPS (ICC WORKSHOPS)
Keywords
Field
DocType
Ambient backscatter, low-power receiver, hybrid analog-digital beamformer
Orders of magnitude (numbers),Mathematical optimization,Fading,Backscatter,Communication channel,Converters,Acoustics,Automatic gain control,High dynamic range,Mathematics,Channel state information
Journal
Volume
ISSN
Citations 
abs/1901.05323
2164-7038
0
PageRank 
References 
Authors
0.34
19
5
Name
Order
Citations
PageRank
Ruifeng Duan15710.36
Estifanos Yohannes Menta221.45
Hüseyin Yigitler37410.20
Riku Jäntti477392.13
Zhu Han511215760.71