scholarly journals A Design of MIMO Prototype in C-Band Frequency for Future Wireless Communications

2020 ◽  
Vol 9 (1) ◽  
pp. 78-84
Author(s):  
N. M. K. Al-Ani ◽  
O. A. S. Al-Ani ◽  
M. F. Mosleh ◽  
R. A. Abd-Alhameed
Keyword(s):  
Wireless Communication ◽  
Mutual Coupling ◽  
Mimo System ◽  
Circular Ring ◽  
Band Frequency ◽  
Wireless Applications ◽  
Single Antenna ◽  
Measurement Results ◽  
The Impact ◽  
System Prototype

The main challenges of MIMO design for future wireless communication is size reduction which leads to more mutual coupling. This paper deals with this problem in order to mitigate the impact of mutual coupling by proposing four elements MIMO prototype each one having a dual polarized patch rectangular microstrips. The idea is to insert annular rectangular opened one ribs in front of each microstrip and in corresponding to circular ring slot etched has etched in the ground. The advantage of such slot is to obtain regular radiation pattern distributed around device body. The four elements with eight ports are incorporated on 67×139 mm2 PCB with FR-4 dielectric layer. The single antenna is simulated CST.STUDIO 2019 resulting an operated frequency of 6.23 GHz with a band of 850 MHz (5.81-6.66) GHz at -10 dB. The fabrication MIMO system prototype is tested to show its measurement results which are match the simulated results. All results confirm of that proposed MIMO prototype which is operated at C-band frequency which is very important for future wireless applications.

scholarly journals Characterizing the Impact of Doppler Effects on Body-Centric LoRa Links with SDR

Sensors ◽  
2021 ◽  
Vol 21 (12) ◽  
pp. 4049
Author(s):  
Thomas Ameloot ◽  
Marc Moeneclaey ◽  
Patrick Van Van Torre ◽  
Hendrik Rogier
Keyword(s):  
Wireless Communication ◽  
Low Power ◽  
Multipath Fading ◽  
Doppler Spread ◽  
Excellent Performance ◽  
Wireless Applications ◽  
Doppler Shifts ◽  
Doppler Effects ◽  
The Impact ◽  
Measurement Campaigns

Long-range, low-power wireless technologies such as LoRa have been shown to exhibit excellent performance when applied in body-centric wireless applications. However, the robustness of LoRa technology to Doppler spread has recently been called into question by a number of researchers. This paper evaluates the impact of static and dynamic Doppler shifts on a simulated LoRa symbol detector and two types of simulated LoRa receivers. The results are interpreted specifically for body-centric applications and confirm that, in most application environments, pure Doppler effects are unlikely to severely disrupt wireless communication, confirming previous research, which stated that the link deteriorations observed in a number of practical LoRa measurement campaigns would mainly be caused by multipath fading effects. Yet, dynamic Doppler shifts, which occur as a result of the relative acceleration between communicating nodes, are also shown to contribute to link degradation. This is especially so for higher LoRa spreading factors and larger packet sizes.

scholarly journals Sum Rate of Multiuser Large-Scale MIMO in the Presence of Antenna Correlation and Mutual Coupling

2019 ◽  
Vol 2019 ◽  
pp. 1-7
Author(s):  
Yusheng Li ◽  
Kang An ◽  
Tao Liang ◽  
Weixin Lu
Keyword(s):  
System Performance ◽  
Mutual Coupling ◽  
Large Scale ◽  
Mimo System ◽  
Base Station ◽  
Closed Form Expression ◽  
Channel State ◽  
Antenna Correlation ◽  
Sum Rate ◽  
The Impact

A multiuser large-scale MIMO system with antenna correlation and mutual coupling is investigated in this paper. Based on the maximum signal-to-interference-plus-noise ratio (SINR) criteria, the optimal beamforming (BF) vector at the base station (BS) for each user is first obtained using statistical channel state information (CSI). Then, a closed-form expression for the achievable sum rate is derived in terms of a finite number of generalized Meijer-G functions, which is applicable to an arbitrary number of array elements and/or users, and provides an efficient means of evaluating the system performance. Finally, numerical results are provided to confirm the validity of the theoretical analysis and show the impact of various channel parameters on the system performance.

Reconfigurable antennas with frequency, polarization, and pattern diversities for multi-radio wireless applications

2015 ◽  
Vol 9 (1) ◽  
pp. 121-132 ◽  
Author(s):  
Chilukuri Sulakshana ◽  
Lokam Anjaneyulu
Keyword(s):  
Wireless Communication ◽  
Radiation Pattern ◽  
Standing Wave ◽  
Return Loss ◽  
Reconfigurable Antennas ◽  
Reconfigurable Antenna ◽  
Patch Antennas ◽  
Band Frequency ◽  
Wireless Applications ◽  
Good Agreement

This paper presents different reconfigurable antennas with frequency, polarization, and pattern diversities. All the antennas have a very simple, novel, and compact structures, which are used for different wireless communication applications. These antennas employ switching for obtaining different reconfigurations. At first, an E-shaped antenna is designed for multi-band frequency reconfigurability. Second, circular and rectangular-shaped patch antennas are designed for achieving diversity in polarization. At last, a pattern reconfigurable antenna is designed with multiport excitation. These antenna performances are analyzed using various parameters such as return loss, radiation pattern, voltage standing wave ratio (VSWR), and gain. The prototypes of the antennas are fabricated and measured results along with simulated ones are presented. Both the results are in good agreement.

Compact Dualband Mimo Antenna for Wireless Communication

2021 ◽  
Author(s):  
Vijetha Tummala ◽  
D Ramakrishna ◽  
R Karthik
Keyword(s):  
Mutual Coupling ◽  
Ground Plane ◽  
Circular Ring ◽  
Antenna System ◽  
Dual Band ◽  
Mimo Antenna ◽  
Wireless Applications ◽  
Multiple Input ◽  
Constant E ◽  
Communications System

Abstract A compact dual band two element planar multiple input and multiple output (MIMO) antenna system is designed for Wireless applications. The Proposed design consists of two printed F shape slot radiators which are arranged symmetrically on the upper layer of the substrate. A patch with I shaped strip on the ground plane helps in reducing the mutual coupling between radiators and A circular ring slot is placed in ground plane to improve the bandwidth of antenna. The proposed module is designed on Fr-4 substrate whose dielectric constant (ɛr) is 4.4. The results show that the MIMO antenna has a resonance frequency at 2.2GHz, which is suitable for Wireless communications system applications and comes with a mutual coupling(s12) less than − 15 dB and the envelop correlation coefficient (ECC) did not exceed 0.02 in the entire operating band of the MIMO antenna part.

Limited Size MIMO Antenna Systems and Mutual Coupling Challenge

2016 ◽  
pp. 176-202
Author(s):  
Nassrin Elamin ◽  
Tharek Rahman
Keyword(s):  
Wireless Communication ◽  
System Performance ◽  
Mutual Coupling ◽  
Mimo System ◽  
Antenna System ◽  
Limited Size ◽  
Mimo Antenna ◽  
High Data ◽  
Isolation Techniques ◽  
Antenna Systems

The wireless communication high data rate is achievable by installing more than one antenna in receiver and transmitter terminals as MIMO antenna. In order to obtain the MIMO gain (Envelope Correlation Coefficient (ECC) = 0.5), the antenna elements must be at least separated by a distance of 0.5? (? is the operating wavelength of 0.7~3.8 GHz which is the frequency range of most of the current wireless communication applications). This value is big relative to limited sizes devices. A practical MIMO antenna should have a low signal correlation between the antenna elements and good matching features for input impedance. Moreover, MIMO system performance can be improved by reducing mutual coupling between closely spaced antenna elements. Miniature high isolated MIMO antenna system has been presented in this chapter; also many MIMO antenna systems were analyzed and categorized based on the implemented isolation techniques. Furthermore several MIMO antenna evaluation methods have been discussed.

Analysis and Design of Planner Wide Band Antenna for Wireless Communication Applications

2021 ◽  
pp. 196-208
Author(s):  
Abdul Rahim ◽  
Praveen Kumar Malik
Keyword(s):  
Wireless Communication ◽  
Wide Band ◽  
Patch Antennas ◽  
Multiple Frequency ◽  
Analysis And Design ◽  
Wireless Applications ◽  
Clear Cut ◽  
Microstrip Patch Antennas ◽  
Single Antenna ◽  
Wireless Environment

Microstrip patch antennas are widely used for enormous wireless applications as they are very compact in size and easy to fabricate and are highly recommended for multiband applications. The antenna must be designed in such a way that a single antenna can be used for multiple applications and multiple frequency ranges with smooth shifting of operating frequency. The antenna must be a wideband such that it can witness the communication between the devices in wireless environment for various applications. This chapter brings some of the important designs which are proposed by various remarkable authors whose contribution towards the wireless communication is a state of the art. The chapter gives a clear-cut idea about how the patch has changed its directions from a traditional design to an utmost complicated yet easy to fabricate fractal in nature multiband application antenna.

scholarly journals Concatenated RS-Convolutional Codes for Cooperative Wireless Communication

2013 ◽  
Vol 7 (1) ◽  
pp. 9-20 ◽  
Author(s):  
Yahya Mohammed Hameed Al-Moliki ◽  
Kamarul Ariffin Bin Noordin ◽  
MHD Nour Hindia ◽  
Mohd Fadzli Bin Mohd Salleh
Keyword(s):  
Wireless Communication ◽  
Mimo System ◽  
Convolutional Codes ◽  
Ieee 802.16E ◽  
Decode And Forward ◽  
Video Broadcasting ◽  
Rs Codes ◽  
Single Antenna ◽  
Channel Codes ◽  
Coded Cooperation

In the last few years, several works have investigated the performance of cooperative wireless systems with various types of channel codes such as Low Density Parity Check (LDPC), Turbo, CRC, convolutional and recently Reed Solomon (RS) codes. These cooperative schemes give power to single antenna mobiles to originate virtual multiple antennas transmitter, MIMO system, by sharing their antennas so that diversity gain is achieved. The most common cooperative schemes are decode and forward (DF) and coded cooperation (CC). Concatenated Reed Solomon and convolutional codes have been used by several wireless communication standards like digital video broadcasting (DVB) standards and IEEE 802.16e WiMAX standard. In this paper, we develop two different coded cooperation schemes and apply them to the mandatory structure of physical layer specifications of IEEE 802.16e WiMAX. The results attained for both coded cooperation schemes present magnificent diversity gains over non-cooperative scheme.

scholarly journals Investigation into the Impact of Mutual Coupling on the Performance of a Multiuser MIMO System Employing Generalized Channel Inversion Technique

2011 ◽  
Vol 2011 ◽  
pp. 1-9 ◽  
Author(s):  
Feng Wang ◽  
Konstanty Bialkowski ◽  
Marek E. Bialkowski
Keyword(s):  
Mutual Coupling ◽  
Mimo System ◽  
Mobile User ◽  
Base Station ◽  
Multiuser Mimo ◽  
Simulation Experiments ◽  
Rate Capacity ◽  
Sum Rate ◽  
The Impact ◽  
System Operating

In this paper, the performance of generalized channel inversion (GCI) technique for a multiuser MIMO system operating under antenna mutual coupling conditions is investigated. The investigation is performed via theoretical derivations and computer simulations. The theoretical derivations show that the presence of mutual coupling may result in an increased performance in terms of sum rate capacity. The simulation experiments confirm the theoretical findings in examples of three groups of numerical results. These results show that the existence of mutual coupling in an array antenna at base station (BS) results in an increased sum rate capacity when antenna interelement spacing at BS is smaller than 0.55 λ. Also it is shown that the presence of mutual coupling at mobile user (MS) terminals results in an increased sum rate capacity when antenna inter-element spacing at MSs is smaller than 0.4 λ. When mutual coupling is considered at both BS and MSs, the system configuration with antenna inter-element spacing equal to 0.45 λat BS and 0.4 λat MSs leads to the highest sum rate capacity.

scholarly journals Performance Analysis and Design Considerations of the Shallow Underwater Optical Wireless Communication System with Solar Noises Utilizing a Photon Tracing-Based Simulation Platform

Electronics ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 632
Author(s):  
Xiaozheng Wang ◽  
Minglun Zhang ◽  
Hongyu Zhou ◽  
Xiaomin Ren
Keyword(s):  
Performance Analysis ◽  
Wireless Communication ◽  
Ambient Noise ◽  
Large Scale ◽  
Delay Spread ◽  
Simulation Platform ◽  
Optical Wireless Communication ◽  
Optical Wireless ◽  
Analysis And Design ◽  
The Impact

The performance of the underwater optical wireless communication (UOWC) system is highly affected by seawater´s inherent optical properties and the solar radiation from sunlight, especially for a shallow environment. The multipath effect and degradations in signal-to-noise ratio (SNR) due to absorption, scattering, and ambient noises can significantly limit the viable communication range, which poses key challenges to its large-scale commercial applications. To this end, this paper proposes a unified model for underwater channel characterization and system performance analysis in the presence of solar noises utilizing a photon tracing algorithm. Besides, we developed a generic simulation platform with configurable parameters and self-defined scenarios via MATLAB. Based on this platform, a comprehensive investigation of underwater channel impairments was conducted including temporal and spatial dispersion, illumination distribution pattern, and statistical attenuation with various oceanic types. The impact of ambient noise at different operation depths on the bit error rate (BER) performance of the shallow UOWC system was evaluated under typical specifications. Simulation results revealed that the multipath dispersion is tied closely to the multiple scattering phenomenon. The delay spread and ambient noise effect can be mitigated by considering a narrow field of view (FOV) and it also enables the system to exhibit optimal performance on combining with a wide aperture.

scholarly journals Implementation of a Zero-Forcing Precoding Algorithm Combined with Adaptive Beamforming Based on WiMAX System

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Hyunwook Yang ◽  
Seungwon Choi
Keyword(s):  
Mimo System ◽  
Multiple Input Multiple Output ◽  
Experimental System ◽  
Multiple Access Interference ◽  
Adaptive Beamforming ◽  
Base Station ◽  
Zero Forcing ◽  
Single Antenna ◽  
Input Multiple Output ◽  
Wimax System

We propose a novel precoding algorithm that is a zero-forcing (ZF) method combined with adaptive beamforming in the Worldwide Interoperability for Microwave Access (WiMAX) system. In a Multiuser Multiple-Input Multiple-Output (MU-MIMO) system, ZF is used to eliminate the Multiple Access Interference (MAI) in order to allow several users to share a common resource. The adaptive beamforming algorithm is used to achieve the desired SNR gain. The experimental system consists of a WiMAX base station that has 2 MIMO elements, each of which is composed of three-array antennas and two mobile terminals, each of which has a single antenna. Through computer simulations, we verified that the proposed method outperforms the conventional ZF method by at least 2.4 dB when the BER is 0.1%, or 1.7 dB when the FER is 1%, in terms of the SNR. Through a hardware implementation of the proposed method, we verified the feasibility of the proposed method for realizing a practical WiMAX base station to utilize the channel resources as efficiently as possible.

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