Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Intelligent Reflecting Surface-Assisted Bistatic Backscatter Networks:
  Joint Beamforming and Reflection Design   Bistatic backscatter communication (BackCom) allows passive tags to transmit
over extended ranges, but at the cost of having carrier emitters either
transmitting at high powers or being deployed very close to tags. In this
paper, we examine how the presence of an intelligent reflecting surface (IRS)
could benefit the bistatic BackCom system. We study the transmit power
minimization problem at the carrier emitter, where its transmit beamforming
vector is jointly optimized with the IRS phase shifts, whilst guaranteeing a
required BackCom performance. A unique feature in this system setup is the
multiple IRS reflections experienced by signals traveling from the carrier
emitter to the reader, which renders the optimization problem highly nonconvex.
Therefore, we propose algorithms based on the minorization-maximization and
alternating optimization techniques to obtain approximate solutions for the
joint design. We also propose low-complexity algorithms based on successive
optimization of individual phase shifts. Our results reveal considerable
transmit power savings in both single-tag and multi-tag systems, even with
moderate IRS sizes, which may be translated to significant range improvements
using the original transmit power or a reduction of the reliance of tags on
carrier emitters located at close range.

23
The categories of this paper are: solv-int
12
The categories of this paper are: nucl-th
11
The categories of this paper are: hep-lat
32
The categories of this paper are: atom-ph
25
The categories of this paper are: patt-sol
24
The categories of this paper are: dg-ga
14
The categories of this paper are: math-ph
10
The categories of this paper are: q-bio
20
The categories of this paper are: acc-phys
13
The categories of this paper are: quant-ph
0
The categories of this paper are: hep-ph
18
The categories of this paper are: econ
4
The categories of this paper are: cond-mat
30
The categories of this paper are: q-alg
28
The categories of this paper are: alg-geom
5
The categories of this paper are: gr-qc