Long-range E-band communication with fiber-equivalent speed is emerging extensively as a critical technology in the next-generation communication. This paper firstly reviews the relevant progress in recent research. A brief survey is presented on high-speed, long-range E-band communication systems and their relevant techniques that are essential to the link design, including antenna, power amplifier (PA), channel, and digital baseband processing. In the second part, we review our recent field trial of a long-range air-to-ground E-band link, which maintains steady transmission from a slow-moving helium balloon to the ground station with a vertical dimension of 20 km. The improvement directions and future research topics are then discussed.
This paper investigates a movable antenna (MA) enabled integrated sensing and communication (ISAC) system under the influence of antenna crosstalk. First, it generalizes the antenna crosstalk model from the conventional fixed-position antenna (FPA) system to the MA scenario. Then, a Cramer-Rao bound (CRB) minimization problem driven by joint beamforming and antenna position design is presented. Specifically, to address this highly non-convex flexible beamforming problem, we deploy a deep reinforcement learning (DRL) approach to train a flexible beamforming agent. To ensure stability during training, a Twin Delayed Deep Deterministic Policy Gradient (TD3) algorithm is adopted to balance exploration with reward maximization for efficient and reliable learning. Numerical results demonstrate that the proposed crosstalk-resilient (CR) algorithm enhances the overall ISAC performance compared to other benchmark schemes.
This paper investigates a practical partially-connected hybrid beamforming transmitter for integrated sensing and communication (ISAC) with distortion from nonlinear power amplification. For this ISAC system, we formulate a communication rate and sensing mutual information maximization problem driven by our distortion-aware hybrid beamforming design. To address this non-convex problem, we first solve for a fully digital beamforming matrix by alternatively solving three sub-problems using manifold optimization (MO) and our derived closed-form solutions. The analog and digital beamforming matrices are then obtained through a decomposition algorithm. Numerical results demonstrate that the proposed algorithm can improve overall ISAC performance compared to traditional beamforming methods.