Biblio

Wireless technology is growing at a fast rate to accommodate the expanding user demands. Currently the radio frequency (RF) spectrum is highly congested and more susceptible to signal fratricide and interference. Therefore, full duplexing techniques are required to enhance the access to the spectrum. Simultaneous Transmit and receive systems (STAR), also known as in-band full duplex systems, are gaining higher attention due to their capability to double spectral efficiency. However, successful implementation of STAR systems requires significant isolation between the transmit and receive signals to reduce self-interference (SI) signal. To minimize this self-interference, front-end coupling cancellation circuits are employed in STAR system. In this paper, an RF coupling suppression circuit is presented based on a hybrid finite impulse response filter (FIR) and resonator architecture. Notably, this newly developed FIR-resonator circuit achieves \textbackslashtextgreater30dB cancellation across a \textbackslashtextgreater1.5:1 bandwidth.

In-Band Full-Duplex (IBFD) Underwater Acoustic (UWA) communication technology plays a major role in enhancing the performance of Underwater acoustic sensor networks (UWSN). Self-Interference (SI) is one of the main inherent challenges affecting the performance of IBFD UWA communication. To reconstruct the SI signal and counteract the SI effect, this is important to estimate the short range channel through which the SI signal passes. Inaccurate estimation will result in the performance degradation of IBFD UWA communication. From the perspective of engineering implementation, we consider that the UWA communication modem shell has a significant influence on the short-range SI channel, which will limit the efficiency of self-interference cancellation in the analog domain to some degree. Therefore we utilize a simplified model to simulate the influence of the structure of the IBFD UWA communication modem on the receiving end. This paper studies the effect of acoustic-shell coupling on near-end self-interference signal of IBFD UWA communication modem. Some suggestions on the design of shell structure of IBFD UWA communication modem are given.

Edge caching has received much attention as a promising technique to overcome the stringent latency and data hungry challenges in the future generation wireless networks. Meanwhile, full-duplex (FD) transmission can potentially double the spectral efficiency by allowing a node to receive and transmit simultaneously. In this paper, we study a cache-aided FD system via delivery time analysis and optimization. In the considered system, an edge node (EN) operates in FD mode and serves users via wireless channels. Two optimization problems are formulated to minimize the largest delivery time based on the two popular linear beamforming zero-forcing and minimum mean square error designs. Since the formulated problems are non-convex due to the self-interference at the EN, we propose two iterative optimization algorithms based on the inner approximation method. The convergence of the proposed iterative algorithms is analytically guaranteed. Finally, the impacts of caching and the advantages of the FD system over the half-duplex (HD) counterpart are demonstrated via numerical results.