Performance Tradeoff Analysis of Hybrid Signaling SWIPT Systems with Nonlinear Power Amplifiers
, Xin Wang 1, Wen Qi 1,2, Xuemin Hong 1, Jianghong Shi 1, Jie Hu 3 and Kun Yang 3Round 1
Reviewer 1 Report
This paper investigates the performance tradeoff for SWIPT networks with nonlinear power amplifiers. The topic is timely and interesting. The reviewer may have the following concerns:
1. The authors state that "This paper is among the first efforts to analyze the performance of hybrid signaling SWIPT systems with nonlinear PA." It would be better to highlight why the conventional analysis cannot be directly applied. Besides, SWIPT systems with nonlinear receiver was studied in [Energy efficient resource allocation in machine-to-machine communications with multiple access and energy harvesting for IoT]. It would be better to mention this.
2. In Figure 3, it would be better to add the noise signal at the receiver side.
3. For the SDNR, it would be better to show the gap of linear PA with nonliner PA, which can show the performance improvement of considering nonlinear PA.
4. In the simulations, it would be better to mention the result of the real system with the theoretical analysis.
5. In the state of art, it is suggested to show the importance of SWIPT with nonlinear power amplifiers in future wireless communications such as [R1].
[R1] Federated Learning for 6G: Applications, Challenges, and Opportunities
Author Response
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Author Response File: 
Author Response.pdf
Reviewer 2 Report
- The novelties pf the paper are somewhat subtle. As the authors claim. this is a study of an existing scheme the assessment of its efficiency. Is this the main idea or something additional? Please comment on this and include the new items in the introduction in a more prominent manner.
- It would be interesting for the authors to include some additional and more challenging examples.
- Please try to elaborate more on the analysis of Section 4.
- What are the limits in the use of eq. 21?
Author Response
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Author Response File: Author Response.pdf
Reviewer 3 Report
This paper presents a systematic study on the performance of hybrid signaling SWIPT systems with memoryless nonlinear transmitter power amplifiers (PAs). Several signaling and power amplifier models are considered. In general, the topic is timely and the results are useful. The paper is well written and easy to follow. The reviewer has only minor comments:
1) For equation (28), can the authors derive the closed-form expression as in (21)?
2) In the simulations, the authors show that polynomial model exhibits slightly higher AM-AM. The reviewer is wondering whether the results are simulated or from practical demos. It is better to use practical hardware to demonstrate the high efficiency.
3) In Appendix A, pls explain why the authors take up r_1/r_{max}=2 as the maximum value point.
4) The literature review is not complete. Recently, there exists some recent contributions that propose to use IRS/RIS to enhance the energy harvesting efficiency. These recent contributions should be acked as follows.
[1]Intelligent reflecting surface aided MIMO broadcasting for simultaneous wireless information and power transfer, IEEE JSAC
[2]Resource allocation for intelligent reflecting surface aided wireless powered mobile edge computing in OFDM systems, IEEE TWC
[3]Self-Sustainable Reconfigurable Intelligent Surface Aided Simultaneous Terahertz Information and Power Transfer (STIPT), arXiv:2102.04053
Author Response
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Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
The revised version of the paper seems ok to me. Actually, the authors have answered to the majority of my comments.
