1,563 research outputs found
Transceiver Design for Wireless Power Transfer for Multiuser MIMO Communication Systems
This chapter describes transceiver design methods for simultaneous wireless power transmission (WPT) and information transmission in two typical multiuser MIMO networks, that is, the MIMO broadcasting channel (BC) and interference channel (IC) networks. The design problems are formulated to minimize the transmit power consumption at the transmitter(s) while satisfying the quality of service (QoS) requirements of both the information decoding (ID) and WPT of all users. The mean-square error (MSE) and the signal-to-interference-noise ratio (SINR) criteria are adopted to characterize the ID performance of the BC network and the IC network, respectively. The designs are cast as nonconvex optimization problems due to the coupling of multiple variables with respect to transmit precoders, ID receivers, and power splitting factors, which are difficult to solve directly. The feasibility conditions of these deign problems are discussed, and effective solving algorithms are developed through alternative optimization (AO) framework and semidefinite programming relaxation (SDR) techniques. Low-complexity algorithms are also developed to alleviate the computation burden in solving the semidefinite programming (SDP) problems. Finally, simulation results validating those proposed algorithms are included
The Nonlinear Talbot Effect of Rogue Waves
Akhmediev and Kuznetsov-Ma breathers are rogue wave solutions of the
nonlinear Schr\"odinger equation (NLSE). Talbot effect (TE) is an image
recurrence phenomenon in the diffraction of light waves. We report the
nonlinear TE of rogue waves in a cubic medium. It is different from the linear
TE, in that the wave propagates in a NL medium and is an eigenmode of NLSE.
Periodic rogue waves impinging on a NL medium exhibit recurrent behavior, but
only at the TE length and at the half-TE length with a \pi-phase shift; the
fractional TE is absent. The NL TE is the result of the NL interference of the
lobes of rogue wave breathers. This interaction is related to the transverse
period and intensity of breathers, in that the bigger the period and the higher
the intensity, the shorter the TE length.Comment: 4 pages, 4 figure
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