Electronically steerable parasitic array radiator (ESPAR) antenna has been proposed to obtain multiple functionality with only a single radio frequency (RF) chain.However, for some signals, the input resistance of ESPAR (EA) becomes negative.A negative would lead oscillatory/unstable behaviour an EA transmit signals.In this work, we address issue by obtaining approximate signals transmission, which are close ideal in mean squared error (MSE) sense, and satisfy requirement that is...

With the rapid development of OFDM (Orthogonal Frequency Division Multiplexing) technology and its own advantages, this has been studied actively in underwater acoustic communication recently to improve data transfer rate reliability. For reason Doppler shift effect channel, eliminating became key whether system can be successfully used communication. In paper, a twice compensation algorithm was proposed, which high precision, low computational complexity implementing easily.

The control of a photovoltaic power generation system with maximum point tracking (MPPT) is the core in solar system. Selecting step length affects speed and output stability directly. This paper analyses variable conductance incremental method, an improved adaptive method. MPPT algorithm proposed based on analysis dynamic characteristics battery P–U characteristic curve. Besides, Matlab simulation model also established. results show that can track accurately. It reduce time dramatically...

Electronically steerable parasitic array radiator (ESPAR) technology enables the implementation of antenna arrays a number elements with single radio frequency (RF) source. Two approaches to achieve stable transmission using an ESPAR (EA) are increase self-resistance EA or transmit signals closely approximating actual that keep stable. Both did not take into account impact limited power on transmission, which is practical constraint amplifier design. We propose new scheme enable provide...

We study a mean-squared-error-based linear transceiver design problem in multiple-input multiple-output cellular system with full-duplex base station serving multiple half-duplex uplink and downlink users simultaneously under the practical per-antenna power constraints. First, an iterative nonlinear Gauss-Seidel type algorithm updating beamformer of each transmit antenna using simple closed-form expressions is proposed. Then, lower complexity proposed based on alternating direction method...

Underwater acoustic channel is a time varying, strong multipath, serious Doppler frequency shift, and high noise interference channel. Aiming at the requirements of stability reliability to support reliable transmission over long distance, direct sequence spread spectrum based on single carrier underwater communication system using dual code (SC-CDMA/DSSC) proposed in this paper. And data frame structure training given out according system. With good correlation characteristics Gold...

The high peak-to-average power ratio (PAPR) and lack of frequency diversity are two well-known issues with orthogonal frequency-division multiplexing (OFDM) modulations, especially over underwater acoustic (UWA) channels. precoding (spreading) technique is a viable way to simultaneously address the aforementioned issues, it has long been researched in wireless communication field. In past decade, also gained increasing attention multicarrier UWA communications. However, comprehensive study...

Mitigating the effects of twin image artifact is one key challenges in holographic lens-free microscopy. This arises due to fact that imaging detectors can only record magnitude hologram wavefront but not phase. Prior work addresses this problem by attempting simultaneously estimate missing phase and reconstruct an object specimen. Here we explore a fundamentally different approach based on post-processing reconstructed using sparse dictionary learning coding techniques originally developed...

In order to improve system performance and reduce receiver hardware complexity cost, we investigate a new multiple-input multiple-output (MIMO) scheme combining maximal-ratio transmit antenna selection (the MRT/RAS scheme). this scheme, single receive antenna, which maximizes the received signal-to-noise (SNR) at receiver, is selected for demodulation. The closed-form outage probability bit error rate (BER) of are presented. simulation demonstrates that can achieve full diversity order, as...

Electronically steerable parasitic array radiator (ESPAR) antennas have been proposed to obtain multiple antenna functionality with only a single radio frequency (RF) chain. However, some signals cannot be transmitted using the ESPAR (EA), because for those signals, real part of input impedance (RII) EA becomes negative. A negative implies that realized and even if it is, will not transmit signal. In this work, we approximate which are close ideal in mean square error (MSE) sense,...

Electronically steerable parasitic array radiator (ESPAR) technology provides multi-antenna transmission with a single radio frequency (RF) unit. In order to achieve stable using an ESPAR antenna (EA), two approaches have been proposed in literature. One is increase the self-resistance of EA, other transmit signals closely approximating actual that keep EA stable. both approaches, no constraint on power was considered. This not case systems, as practical amplifier normally has limited peak...

Aiming at the demand for precise positioning of underwater device in marine controllable source electromagnetic (CSEM) exploration system, an acoustic method with one shipborne interrogator and two GPS buoys is proposed. Using numerical simulation method, influence ranging deviation attitude angle on system accuracy studied. The results show effectiveness proposed which lays a theoretical basis equipment development test measurement.