Abstract There has been much interest in developing a thin-film solar cell because it is lightweight and flexible. The GaAs top contender the market that high power conversion efficiency (PCE) compared to of other cells. are two common structures for cell: n (emitter)-on-p (base) p-on-n. former performs better due its collection electron diffusion length p-type base region longer than hole n-type region. However, limited fabricate highly efficient n-on-p single-junction thin film on flexible...

We consider the downlink of a cellular network with multiple cells and multi-antenna base stations. Our model includes distance-dependent pathloss, arbitrary clusters cooperating cells, general "fairness" requirements. Beyond Monte Carlo simulation, no efficient computation method to evaluate ergodic throughput such systems has been presented, yet. Furthermore, for practical size tens hundreds users per cell, even simulation becomes challenging. develop an analytic framework based on...

Abstract Gallium arsenide (GaAs) photovoltaic (PV) cells have been widely investigated due to their merits such as thin‐film feasibility, flexibility, and high efficiency. To further increase performance, a wider bandgap PV structure indium gallium phosphide (InGaP) has integrated in two‐terminal (2T) tandem configuration. However, it increases the overall fabrication cost, complicated tunnel‐junction diode connecting subcells are inevitable, materials limited by lattice matching. Here,...

Abstract GaAs thin‐film solar cells have high efficiency, reliability, and operational stability, making them a promising solution for self‐powered skin‐conformal biosensors. However, inherent device thickness limits suitability such applications, uncomfortable unreliable in flexural environments. Therefore, reducing the rigidity becomes crucial integration with skin‐compatible electronic devices. Herein, this study demonstrated novel one‐step surface modification bonding methodology,...

In this paper, we investigate the outage and ergodic capacity of downlink distributed antenna systems (DAS) where each unit (DAU) has multiple antennas with per-DAU power constraint. We first derive optimal beamforming vector in a closed form by applying matrix minor condition to relax positive semi-definite observe that our derived solution maximum ratio transmission per DAU full power. Based on beamforming, under Rayleigh fading channels are analyzed. To end, show distribution received...

Intelligent systems require a systematic way to represent and handle temporal information containing uncertainty. In particular, logical framework is needed that can uncertain its relationships with formulae. Fuzzy linear logic (FLTL), generalization of propositional (PLTL) fuzzy events states defined on time model, was previously proposed for this purpose. However, many are best represented by branching models in which each state have more than one possible future path. paper, (FBTL)...

Recently, biocompatible optical sources have been surfacing for new-rising biomedical applications, allowing them to be used multi-purpose technologies such as biological sensing, optogenetic modulation, and phototherapy. Especially, vertical-cavity surface-emitting laser (VCSEL) is in the spotlight a prospective candidate owing its low-driving current performance, low-cost, package easiness accordance with two-dimensional (2D) arrays structure. In this study, we successfully demonstrated...

In this letter, we analyze the sum rate of random beamforming (RBF) for downlink multi-antenna systems in presence other cell interference (OCI). Employing extreme value theory, an expression asymptotic ergodic with a large number users is derived from limiting distribution sample maximum received signal-to-interference-plus-noise ratio. Based on our result, scaling law multiuser diversity gain also exhibited context RBF OCI, which shown to coincide previous result without interferers....

Abstract High‐performance continuous‐wave (CW) vertical‐cavity surface‐emitting lasers (VCSELs) rely on efficient thermal management for which top‐emitting 930 nm thin‐film VCSELs are integrated with a copper‐plated heatsink by using double‐transfer technique, exhibiting the low‐power consumption, high‐power, and temperature‐stable VCSEL operation. In this study, structures, including highly n‐doped GaAs ohmic lattice‐matched InGaP etch‐stop layers, epitaxially grown via low‐pressure...

It has been shown that the performance of multiple-input multiple-output (MIMO) spatial multiplexing systems is significantly degraded when correlation exists between transmit and receive antenna pairs. In this paper, we investigate designs a new statistical precoder for with maximum likelihood (ML) receiver which requires only statistics at transmitter. Two kinds closed-form solution precoders based on rotation power allocation are proposed by means maximizing minimum Euclidean distance...

We consider the downlink of a cellular network with multiple cells and multi-antenna base stations under arbitrary inter-cell cooperation, realistic distance-dependent pathloss, general “fairness” requirements. Beyond Monte Carlo simulation, no efficient computation method to evaluate ergodic throughput such systems has been provided so far. propose an analytic based on combination large random matrix theory Lagrangian optimization. The proposed is computationally much more than simulation...

Ultrathin Ge single‐junction (1J) solar cells transferred onto a flexible substrate are envisioned to open up novel lattice‐matched thin‐film InGaP/(In)GaAs/Ge tandem cell for enabling highly efficient, low‐cost, and light‐weight devices. The ultrathin 1J structures epitaxially grown GaAs via low‐pressure metal–organic chemical vapor deposition system using an isobutylgermane metalorganic source as precursor. A simple fast epitaxial lift‐off method allows the epi transfer substrates, by...

The optimization of the weighted ergodic sum rate is considered for downlink a cellular networks with multiple cells and multi-antenna base stations. We focus on large system limit where number station antennas users per cell go to infinity fixed ratio. consider two extreme cases full inter-cell cooperation (network MIMO) no (single-cell multiuser MIMO). Using random matrix theory Lagrangian optimization, we obtain numerical algorithm that exactly computes maximum in this asymptotic regime....

We experimentally demonstrate the direct detection of 40-Gb/s OFDM signal generated by using an electro-absorption modulated laser after transmission over 80-km standard single-mode fiber Kramers-Kronig receiver.

This paper introduces a new efficient design scheme for spatial multiplexing (SM) systems over closed loop multiple- input multiple-output (MIMO) wireless channels. Extending the orthogonalized (OSM) which was developed recently transmitting two data streams, we propose SM where larger number of streams can be supported. To achieve this goal, partition into several subblocks and execute block-diagonalization process at receiver. The proposed still guarantees single- symbol maximum likelihood...

Block diagonalization (BD) is an attractive method for approaching sum capacity in multiuser multiple-input multiple-output (MIMO) broadcast channels. However, when channel state information (CSI) limited, the performance of BD degraded because inter-user interference cannot be completely eliminated. In this paper, we study limited feedback systems where a large number users are supported per cell. Based on estimate received signal-to-interference-plus-noise ratio (SINR), present efficient...

In order to employ adaptive modulation and coding, it is important determine the post-detected signal-to-noise ratio (SNR) of system. this paper, we propose a new method predict link performance for multiple-input multiple-output (MIMO) systems with maximum likelihood detector (MLD) which adopt single channel encoder. By using relation between upper lower bound MIMO system MLD defining dynamic SNR penalty, show that possible represent as scalar value high accuracy. adopting proposed coding...

In this paper, we propose an efficient carrier frequency offset (CFO) estimation technique based on the space alternating generalized expectation-maximization (SAGE) for uplink orthogonal division multiple access (OFDMA) systems. general, SAGE method transforms a multidimensional search problem into sequence of one-dimensional searches, which greatly simplifies procedure. However, conventional algorithms require large amount computations to estimate CFO due exhaustive grid search. To reduce...

Abstract Thin-film vertical cavity surface emitting lasers (VCSELs) mounted onto heatsinks open up the way toward low-power consumption and high-power operation, enabling them to be widely used for energy saving high-speed optical data communication three-dimensional sensor applications. There are two conventional VCSEL polarity structures: p-on-n n-on-p polarity. The former is more preferably owing reduced series resistance of n-type bottom distributed Bragg reflection (DBR) as well lower...

When channel state information (CSI) is available at the transmitter, system throughput can be enhanced by adaptive transmissions and opportunistic multiuser scheduling. In this paper, we consider multi-input multi-output (MIMO) systems employing bit-interleaved coded orthogonal frequency division multiplexing (BIC-OFDM). We first propose a bit- loading algorithm based on Levin-Campello for BIC-OFDM. Then will apply to MIMO with finite set of constellations, reassigning residual power each...

In this paper, we study multiple-input single-output downlink cellular systems which jointly design adaptive inter-cell interference cancellation and user scheduling assuming that partial channel state information (CSI) is shared among base stations (BSs). Since the optimal solution requires high complexity, propose a new low complexity algorithm selects best users their beamforming (BF) strategies in terms of maximizing weighted sum rate. To end, first develop simple threshold criterion for...