Logo
ScienceStack
Table of Contents
Fetching ...
Sign In

Discrete RIS Enhanced Space Shift Keying MIMO System via Reflecting Beamforming Optimization

Xusheng Zhu, Qingqing Wu, Wen Chen, Xinyuan He, Lexi Xu, Yaxin Zhang

TL;DR

Simulation results verify the superiority of the proposed RIS-SSK-MIMO scheme and demonstrate the impact of the number of RIS elements, the number of phase quantization bits, and the number of receive and transmit antennas in terms of reliability.

Abstract

In this paper, a discrete reconfigurable intelligent surface (RIS)-assisted spatial shift keying (SSK) multiple-input multiple-output (MIMO) scheme is investigated, in which a direct link between the transmitter and the receiver is considered. To improve the reliability of the RIS-SSK-MIMO scheme, we formulate an objective function based on minimizing the average bit error probability (ABEP). Since the reflecting phase shift of RIS is discrete, it is difficult to address this problem directly. To this end, we optimize the RIS phase shift to maximize the Euclidean distance between the minimum constellations by applying the successive convex approximation (SCA) and penaltyalternating optimization method. Simulation results verify the superiority of the proposed RIS-SSK-MIMO scheme and demonstrate the impact of the number of RIS elements, the number of phase quantization bits, and the number of receive and transmit antennas in terms of reliability.

Discrete RIS Enhanced Space Shift Keying MIMO System via Reflecting Beamforming Optimization

TL;DR

Simulation results verify the superiority of the proposed RIS-SSK-MIMO scheme and demonstrate the impact of the number of RIS elements, the number of phase quantization bits, and the number of receive and transmit antennas in terms of reliability.

Abstract

In this paper, a discrete reconfigurable intelligent surface (RIS)-assisted spatial shift keying (SSK) multiple-input multiple-output (MIMO) scheme is investigated, in which a direct link between the transmitter and the receiver is considered. To improve the reliability of the RIS-SSK-MIMO scheme, we formulate an objective function based on minimizing the average bit error probability (ABEP). Since the reflecting phase shift of RIS is discrete, it is difficult to address this problem directly. To this end, we optimize the RIS phase shift to maximize the Euclidean distance between the minimum constellations by applying the successive convex approximation (SCA) and penaltyalternating optimization method. Simulation results verify the superiority of the proposed RIS-SSK-MIMO scheme and demonstrate the impact of the number of RIS elements, the number of phase quantization bits, and the number of receive and transmit antennas in terms of reliability.

Paper Structure

This paper contains 13 sections, 1 theorem, 21 equations, 5 figures, 1 algorithm.

Table of Contents

  1. Introduction
  2. System Model
  3. Transmission
  4. ABEP
  5. Proposed Solution
  6. Problem Formulation
  7. Proposed Iterative Design Method for $\mathbf{v}$
  8. Proposed Design Method for $\mathbf{u}$
  9. Alternative Opimization for $\mathbf{v}$ and $\mathbf{u}$
  10. Penalty-Alterative Algorithm
  11. Complexity Analysis
  12. Simulation Results
  13. Conclusion

Key Result

Lemma 1

For given $\rho$, the alternating iteration optimization method is converge.

Figures (5)

  • Figure 1: System model.
  • Figure 2: Comparison of ABEP performance of the proposed scheme with different benchmark schemes.
  • Figure 3: Impact of RIS phase quantisation bits on ABEP performance.
  • Figure 4: Impact of the number of receive antennas on ABEP performance.
  • Figure 5: Impact of modulation order on ABEP performance.

Theorems & Definitions (2)

  • Remark 1
  • Lemma 1