This letter investigates a virtual reality (VR) delivery system, where the original VR contents requested by all users are stored at macro base station (MBS). To reduce latency, MBS can either transmit data or computed to multiple aided an intelligent reflecting surface (IRS) prevent attacks from eavesdropper with imperfect channel state information (CSI). We jointly optimize transmission polic...

Malicious jamming launched by smart jammers can attack legitimate transmissions, which has been regarded as one of the critical security challenges in wireless communications. With this focus, paper considers use an intelligent reflecting surface (IRS) to enhance anti-jamming communication performance and mitigate interference adjusting elements at IRS. Aiming against a jammer, optimization pro...

For achieving efficient data aggregation and energy supply in Internet of Things, this paper investigates the optimal design for an intelligent reflecting surface (IRS)-aided backscatter sensor network with over-the-air computation (AirComp). To ensure accuracy aggregation, presents a mean-squared error (MSE) minimization problem via jointly optimizing normalization factor, power splitting rati...

We have collected polarimetric ice sounding radar data on Brunt, George VI and Ronne ice shelves using a vector network analyser as a continuous wave step-frequency radar. Being a wideband phase sensitive instrument, the radar allowed the vectorial nature of the interaction between radio waves and the ice and reflecting surface to be explored. Single crystals of ice are birefringent not only at...