This paper investigates intelligent reflecting surface based backscatter communication (IRS-BackCom), in order to realize computational task offloading of energy-constrained mobile edge computing network a self-sustainable manner. Specifically, the system operation is divided into two phases. In first one, ambient signal energy from power beacon (PB) either provides supply local and harvesting ...

Reconfigurable intelligent surface (RIS) based communications have emerged as a new paradigm. This letter proposes differential reflecting modulation (DRM) scheme for RIS communication systems. In DRM, information bits are jointly carried by the activation permutations of patterns and phases transmitted signals, leading to that DRM can work without any channel state (CSI) at transmitter, or rec...

In this letter, we consider a multicast system where single-antenna transmitter sends common message to multiple users, aided by an intelligent reflecting surface (IRS) equipped with N passive elements. Prior works on IRS have mostly assumed the availability of channel state information (CSI) for designing its beamforming. However, acquisition CSI requires substantial training overhead that inc...

This paper considers a secure multigroup multicast multiple-input single-output (MISO) communication system aided by an intelligent reflecting surface (IRS). Specifically, we aim to minimize the transmit power at Alice via jointly optimizing beamformer, artificial noise (AN) vector and phase shifts IRS subject secrecy rate constraints as well unit modulus of shifts. To tackle optimization probl...

This paper considers a two-user downlink transmission in intelligent reflecting surface (IRS) aided network over fading channels. Particularly, non-orthogonal multiple access (NOMA) and two orthogonal (OMA) schemes, namely, time division (TDMA) frequency (FDMA), are studied. The objective is to maximize the system average sum rate for delay-tolerant transmission. We propose adjustment dynamic p...

This paper aims to investigate the benefit of using intelligent reflecting surface (IRS) in multi-user multiple-input single-output (MU-MISO) systems, presence eavesdroppers. We maximize weighted sum secrecy rate by jointly designing secure beamforming (BF), artificial noise (AN), as well phase shift IRS. An alternating optimization (AO) method is proposed deal with formulated non convex proble...

Intelligent reflecting surfaces (IRSs) are a promising technology for enhancing coverage and spectral efficiency, both in the sub-6 GHz millimeter wave (mmWave) bands. Existing approaches to leverage benefits of IRS involve use resource-intensive channel estimation step followed by computationally expensive algorithm optimize reflection coefficients at IRS. In this work, focusing on band commun...

Spectrum sensing is a key enabling technique for cognitive radio (CR), which provides essential information on the spectrum availability. However, due to severe wireless channel fading and path loss, primary user (PU) signals received at CR or secondary (SU) can be practically too weak reliable detection. To tackle this issue, we consider in letter new intelligent reflecting surface (IRS)-aided...