scholarly journals INCREASING ION SELECTIVE ELECTRODES PERFORMANCE USING NEURAL NETWORKS

2014 ◽  
pp. 17-24
Author(s):  
O. Postolache ◽  
P. Girao ◽  
M. Pereira ◽  
Helena Ramos
Keyword(s):  
Virtual Instrument ◽  
Transfer Functions ◽  
Low Cost ◽  
Multiple Input Multiple Output ◽  
Control Unit ◽  
Measuring System ◽  
Ion Selective Electrodes ◽  
Neural Processing ◽  
Data Acquisition Board ◽  
Input Multiple Output

This paper reports the implementation of a neural processing structure as a component of an intelligent measuring system that uses ion selective electrodes (ISEs) as sensing elements of heavy metal ions (Pb+2, Cd+2) concentration. The neural network (NN), designed and implemented to reduce errors due to ion interference and to pH and temperature variations, is of the multiple-input multiple-output Multilayer Percepton (MLP-NN) type. The NN is a component of a virtual instrument that includes a PC laptop, a PCMCI data acquisition board with associated conditioning circuits and the specific ISE sensors. A practical approach concerning the optimal neural processing solution (number of NN structures, number of neurons, neuron transfer functions) to increase the performance of low cost ISEs is presented. Results are presented to evaluate the performance of the NN intelligent ISE system and to discuss the possibility of transferring the acquisition and processing task to a low cost acquisition and control unit such as a microcontroller.

scholarly journals An Efficient Signal Reconstruction Algorithm for Stepped Frequency MIMO-SAR in the Spotlight and Sliding Spotlight Modes

2014 ◽  
Vol 2014 ◽  
pp. 1-8
Author(s):  
Jiajia Zhang ◽  
Guangcai Sun ◽  
Mengdao Xing ◽  
Zheng Bao ◽  
Fang Zhou
Keyword(s):  
Efficient Algorithm ◽  
Low Cost ◽  
Signal Reconstruction ◽  
Multiple Input Multiple Output ◽  
Reconstruction Algorithm ◽  
Synthetic Aperture ◽  
Two Dimensional ◽  
Multiple Input ◽  
Input Multiple Output ◽  
Stepped Frequency

Multiple-input multiple-output (MIMO) synthetic aperture radar (SAR) using stepped frequency (SF) waveforms enables a high two-dimensional (2D) resolution with wider imaging swath at relatively low cost. However, only the stripmap mode has been discussed for SF MIMO-SAR. This paper presents an efficient algorithm to reconstruct the signal of SF MIMO-SAR in the spotlight and sliding spotlight modes, which includes Doppler ambiguity resolving algorithm based on subaperture division and an improved frequency-domain bandwidth synthesis (FBS) method. Both simulated and constructed data are used to validate the effectiveness of the proposed algorithm.

Experimental Study on New Wave Measurement Using Passive Underwater Acoustics

2008 ◽  
Author(s):  
Jing Li ◽  
Dingyong Yu ◽  
Huaxing Liu
Keyword(s):  
Virtual Instrument ◽  
Low Cost ◽  
Measuring System ◽  
Time Data ◽  
Significant Wave ◽  
Wave Measurement ◽  
Wave Heights ◽  
Mean Wave Period ◽  
Passive Acoustic ◽  
User Friendly

The passive acoustic-based wave measurement via hydrophones is presented in this paper. It has the potential to measure non-intrusively, implement with low cost and with higher resolution. Details of experiments, real-time data recording and processing are described respectively. Particularly, the portable data acquisition system based on virtual instrument technique is designed to make the in situ measurement convenient and user-friendly. Special emphasis is put on FFT filtering technique to band pass the signal fast and efficiently. The key wave parameters, i.e. the mean wave period and the significant wave height, can be obtained from the comparatively safe and stable underwater by means of submerged hydrophones. Considering the pressure sensor has been widely used in the ocean wave measurement, it is deployed simultaneously to test the feasibility of the new system. The result shows that the present measuring system can give satisfactory measurement of significant wave heights and average wave periods in shallow water despite of the little deviation.

UWB MIMO antenna with common radiator

2016 ◽  
Vol 9 (3) ◽  
pp. 573-580 ◽  
Author(s):  
Garima Srivastava ◽  
B. K. Kanuijia ◽  
Rajeev Paulus
Keyword(s):  
Low Cost ◽  
Multiple Input Multiple Output ◽  
Impedance Bandwidth ◽  
Rectangular Slot ◽  
Mimo Antenna ◽  
Circular Patch ◽  
Capacity Loss ◽  
Compact Size ◽  
Multiple Input ◽  
Input Multiple Output

A compact printed 2 × 2 ultrawideband (UWB) multiple input multiple output (MIMO) antenna with a single circular patch as a common radiator for both the antenna elements is presented in this paper. A single circular patch is excited by two tapered CPW feeds for dual polarization. To improve the isolation between two ports, a rectangular slot of dimension L1 × W1 is created in the radiator. The UWB MIMO antenna has impedance bandwidth of 3–12 GHz with a isolation better than 17 dB between the two ports. The envelope correlation coefficient and the capacity loss are evaluated to ensure the good diversity performance of UWB MIMO antenna. The antenna has a compact size of 45 × 45 mm2 and is fabricated on low cost FR4 substrate and measured using Agilent VNA. The simulated and measured results show that the proposed UWB antenna is good candidate for UWB MIMO applications.

scholarly journals A Survey on Massive MIMO Systems in Presence of Channel and Hardware Impairments

Sensors ◽  
2019 ◽  
Vol 19 (1) ◽  
pp. 164 ◽  
Author(s):  
Zahra Mokhtari ◽  
Maryam Sabbaghian ◽  
Rui Dinis
Keyword(s):  
Massive Mimo ◽  
Orthogonal Frequency Division Multiplexing ◽  
Mimo Systems ◽  
Low Cost ◽  
Multiple Input Multiple Output ◽  
Base Station ◽  
Aging Effects ◽  
Hardware Impairments ◽  
Single Carrier ◽  
Input Multiple Output

Massive multiple input multiple output (MIMO) technology is one of the promising technologies for fifth generation (5G) cellular communications. In this technology, each cell has a base station (BS) with a large number of antennas, allowing the simultaneous use of the same resources (e.g., frequency and/or time slots) by multiple users of a cell. Therefore, massive MIMO systems can bring very high spectral and power efficiencies. However, this technology faces some important issues that need to be addressed. One of these issues is the performance degradation due to hardware impairments, since low-cost RF chains need to be employed. Another issue is the channel estimation and channel aging effects, especially in fast mobility environments. In this paper we will perform a comprehensive study on these two issues considering two of the most promising candidate waveforms for massive MIMO systems: Orthogonal frequency division multiplexing (OFDM) and single-carrier frequency domain processing (SC-FDP). The studies and the results show that hardware impairments and inaccurate channel knowledge can degrade the performance of massive MIMO systems extensively. However, using suitable low complex estimation and compensation techniques and also selecting a suitable waveform can reduce these effects.

Design and Analysis of Rectangular Microstrip Patch Array Antenna on 28 GHz Band for Future of 5G

2021 ◽  
pp. 25-43
Author(s):  
Ashraf Aboshosha ◽  
Mohamed B. El-Mashade ◽  
Ehab A. Hegazy
Keyword(s):  
Low Cost ◽  
Multiple Input Multiple Output ◽  
Array Antenna ◽  
Spectrum Efficiency ◽  
Microstrip Patch ◽  
Fifth Generation ◽  
Data Rates ◽  
Input Multiple Output ◽  
Mobile Phone Applications ◽  
Mm Waves

The narrow beam widths generally associated with antennas at higher frequencies has led to the study of using advanced multiple-input multiple-output (MIMO) and adaptive beam-forming. These antenna technologies are overcoming some of the challenging propagation characteristics of mm waves and could increase the spectrum efficiency, provide higher data rates, and adequate reasonable coverage for mobile broadband services. With the potential for higher 10+GHz frequencies as well as mm waves deployment, most 5G candidates bands in 20 to 50 GHz. The frequency band of 5G is proposed and demonstrated above 24GHz such as 28GHz to 38GHz. In this chapter, the authors present a design of 28GHz for 4 Elements microstrip patch array antenna for future fifth generation (5G) mobile-phone applications. The designed antenna can be implemented using low cost FR-4 substrates, while maintaining good performance in terms of gain and efficiency. In addition, the simulated results show that the antenna has the S11 response less than -10 dB in the frequency range of 22 to 34 GHz.

scholarly journals A multi channel coupling based approach for the prediction of the channel capacity of MIMO-systems

2011 ◽  
Vol 9 ◽  
pp. 153-158
Author(s):  
F. Hagebölling ◽  
U. Zölzer
Keyword(s):  
Channel Capacity ◽  
Transfer Functions ◽  
Mimo Systems ◽  
Multiple Input Multiple Output ◽  
Prediction Method ◽  
Major Influence ◽  
Prediction Errors ◽  
Channel Coupling ◽  
Input Multiple Output ◽  
Transmission Quality

Abstract. When installing Multiple Input Multiple Output (MIMO)-systems, the antenna positioning has a major influence upon the achievable transmission quality. To determine those antenna positions, which maximize the transmission quality, in adequate time, a computer based prediction of the channel capacity is imperative. In this paper, we will show that Ray Tracing, which is a very popular prediction method and well suited for the prediction of transfer functions or power delay profiles, produces unacceptable errors when predicting the channel capacity of MIMO-systems. Furthermore we identify the source of the prediction errors and present a new algorithm, based on an approach known as Multi Channel Coupling (MCC), which avoids this error source. Finally a comparison of the prediction results of our algorithm with prediction results gained with an Image Ray Tracer as well as with measured results is used to show the formidable increasement of prediction accuracy which can be gained by using our algorithm.

scholarly journals A Review of 5G Power Amplifier Design at cm-Wave and mm-Wave Frequencies

2018 ◽  
Vol 2018 ◽  
pp. 1-16 ◽  
Author(s):  
D. Y. C. Lie ◽  
J. C. Mayeda ◽  
Y. Li ◽  
J. Lopez
Keyword(s):  
Power Amplifier ◽  
Power Efficiency ◽  
Low Cost ◽  
Multiple Input Multiple Output ◽  
Wave Spectrum ◽  
System Architectures ◽  
Mimo Antennas ◽  
Rf Transmitters ◽  
Input Multiple Output ◽  
Amplifier Design

The 5G wireless revolution presents some dramatic challenges to the design of handsets and communication infrastructures, as 5G targets higher than 10 Gbps download speed using millimeter-wave (mm-Wave) spectrum with multiple-input multiple-output (MIMO) antennas, connecting densely deployed wireless devices for Internet-of-Everything (IoE), and very small latency time for ultrareliable machine type communication, etc. The broadband modulation bandwidth for 5G RF transmitters (i.e., maximum possibly even above 1 GHz) demands high-power efficiency and stringent linearity from its power amplifier (PA). Additionally, the phased-array MIMO antennas with numerous RF front-ends (RFFEs) will require unprecedented high integration level with low cost, making the design of 5G PA one of the most challenging tasks. As the centimeter-wave (cm-Wave) 5G systems will probably be deployed on the market earlier than their mm-Wave counterparts, we will review in this paper the latest development on 15 GHz and 28 GHz 5G cm-Wave PAs extensively, while also covering some key mm-Wave PAs in the literature. Our review will focus on the available options of device technologies, novel circuit and system architectures, and efficiency enhancement techniques at power back-off for 5G PA design.

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