Cooperative Reflection Design With Timing Offsets in Distributed Multi-RIS Communications

  title={Cooperative Reflection Design With Timing Offsets in Distributed Multi-RIS Communications},
  author={Yaqiong Zhao and Wei Xu and Huan Sun and Derrick Wing Kwan Ng and Xiaohu You},
  journal={IEEE Wireless Communications Letters},
  • Yaqiong Zhao, Wei Xu, +2 authors X. You
  • Published 27 July 2021
  • Computer Science, Engineering, Mathematics
  • IEEE Wireless Communications Letters
This letter investigates a wireless communication system deploying distributed reconfigurable intelligent surfaces (RISs). Existing works have assumed that perfect timing synchronization is available among all the cooperative RISs. For practical considerations, we first study cooperative reflection design for multi-RIS-aided communication systems taking into account timing synchronization errors. We aim to minimize the mean-squared error of the recovered data in the presence of timing offsets… Expand

Figures from this paper


Timing Synchronization in Decode-and-Forward Cooperative Communication Systems
This paper addresses the joint timing and channel estimation problem, and furthermore the resynchronization of multiple timing offsets in a cooperative relay system and a new bound called weighted Bayesian CRB is proposed. Expand
Distributed IRS With Statistical Passive Beamforming for MISO Communications
This letter investigates a multiple-input single-output (MISO) system deploying distributed IRSs and proposes an efficient design of passive reflecting beamforming for the IRSs to exploit statistical channel state information (CSI) and analyze the achievable rate of the network taking into account the impact of CSI estimation error. Expand
Intelligent Reflecting Surface Meets OFDM: Protocol Design and Rate Maximization
An IRS-enhanced orthogonal frequency division multiplexing (OFDM) system under frequency-selective channels is studied and an efficient algorithm to obtain a high-quality suboptimal solution is proposed, by alternately optimizing the power allocation and the passive array coefficients in an iterative manner. Expand
Resource Allocation for Wireless Communications with Distributed Reconfigurable Intelligent Surfaces
This paper investigates the problem of resource allocation for a wireless communication network with distributed reconfigurable intelligent surfaces with RISs and proposes an alternating algorithm, which achieves up to 27% and 68% gains in terms of the energy efficiency compared to the conventional RIS scheme and amplify-and-forward relay scheme. Expand
Weighted Sum-Rate Maximization for Intelligent Reflecting Surface Enhanced Wireless Networks
This work focuses on the downlink of an IRSaided multiuser multiple-input single-output (MISO) system and proposes an efficient algorithm with closed-form solutions for the passive beamforming, which is applicable to both the discrete phase- shift IRS and the continuous phaseshift IRS. Expand
Intelligent Reflecting Surface-Assisted Multi-User MISO Communication: Channel Estimation and Beamforming Design
This paper exploits the prior knowledge of the large-scale fading statistics at the BS to derive the Bayesian minimum mean squared error (MMSE) channel estimates under a protocol in which the IRS applies a set of optimal phase shifts vectors over multiple channel estimation sub-phases. Expand
Large Intelligent Surface-Assisted Wireless Communication Exploiting Statistical CSI
Numerical results show that using the proposed phase shift design can achieve the maximum ergodic spectral efficiency, and a 2-bit quantizer is sufficient to ensure spectral efficiency degradation of no more than 1 bit/s/Hz. Expand
Robust and Secure Wireless Communications via Intelligent Reflecting Surfaces
Simulation results show that IRSs can significantly improve the system secrecy performance compared to conventional architectures without IRS, and unveil that, for physical layer security, uniformly distributing the reflecting elements among multiple IRSs is preferable over deploying them at a single IRS. Expand
Weighted Sum-Rate Maximization for Multi-IRS Aided Cooperative Transmission
This letter investigates multiple intelligent reflecting surfaces (IRSs) aided wireless network, where the IRSs are deployed to cooperatively assist communications between a multi-antenna baseExpand
Cascaded Channel Estimation for IRS-Assisted mmWave Multi-Antenna With Quantized Beamforming
This letter derives the optimized channel estimator in a closed form by reformulating the problem of cascaded channel estimation in an intelligent reflecting surface (IRS)-assisted millimeter wave (mmWave) multi-antenna system, leveraging the typical mean-squared error (MSE) criterion. Expand