Design Study of a Miniaturized Multi-layered Antenna-in-package for 2.4 GHZ Wireless Communication

This paper proposes a novel miniaturization technique to enhance the radiation properties of small multi-layer patch antenna used in packaged circuits. The multilayered antenna design is composed of three layers with different shapes. An enhancement on the radiation properties has been obtained by optimizing the geometry of the radiated element and the parasitic conductor of the middle layer. The whole design has been implemented on the FR4 substrate with dielectric constant of 4.4, thickness of 1.6 mm and Copper thickness of 5 μm. The first layer is a driven element while second and the third layer are parasitic patch elements. The optimized multilayer antenna has a very small size of 12×6×5 mm^3. Considering the small size of the antenna, a detailed study of the parameter affecting the radiation has been considered to force the antenna to operate at 2.4 GHz band. Miniaturization techniques based on the current distribution have been also taken into account to shift down the resonant frequency and reduces more and more the antenna size at the designed operating frequency. The miniaturized antenna maintains performant radiation characteristics in terms of reflexion coefficient, bandwidth and directivity. All developed antennas are simulated using the commercial Electromagnetic CST Microwave Studio software. Achieved results demonstrate a good performance with low cost and compact size

Experimental Analysis of IoT Networks Based on LoRa/LoRaWAN under Indoor and Outdoor EnvirMedusonments: Performance and Limitations

Nowadays, Internet of Things (IoT) has multiple applications in different fields. This concept allows physical devices to connect to the internet in order to establish a strong infrastructure that facilitates many device control and monitoring tasks. Low Power Wide Area (LPWA) communication protocols become widely used for IoT networks because of their low power consumption and the broad range communication. LPWA enables devices to transmit small amounts of data in a long distance. Among LPWA protocols, LoRa technology gained a lot of interest recently from the research community and many companies. LoRa is a long range and low power wireless communication technology regulated by the LoRaWAN standard. It can be o good candidate to deploy node network where long distance and extended battery life is required. A LoRaWAN architecture is deployed in a star-of-stars topology and based on a systematic evaluation of a long-term operation of the network monitoring. This works describes experimental results of testing LoRa in indoor and outdoor environments to understand how it works, evaluate its performance, and limitations. As expected, results show that LoRa performs better outdoor. It is also interesting to note that elevating the gateway in order to have a free line of sight with the IoT node, or close to it, increases the signal quality received by the end-node devices, and consequently, longer distances can be achieved

Packaging Technique for Gain Improvement of Multi-resonance CPW-fed Antenna for Satellite Applications

A suitable technique for gain improvement of multi-resonance CPW-fed antenna for satellite application at Ku-, K- and Ka-bands for user terminals is presented in this paper. New concept of stacking numerous layers with different dielectric material has been also presented. The conventional antenna design consists of a CPW-fed patch antenna with modified CPW elements printed on Rogers TMM4 substrate. In order to improve the antenna performance in term of gain and bandwidth, we propose two different configurations. The first one consists of designing a stacked structure by adding on the top of the single antenna an additional layer with parasitic elements. The dielectric added consists in Rogers RO3010 substrate with a high permittivity of 10.2. The proposed antenna is formed by two layers separated by an air gap; this new configuration provides major reduction on antenna beam width and allows gain enhancement. The second one implement the design of 2×1 and 4×1 series feed antenna arrays based on the conventional CPW-fed antenna. These array configurations are used to achieve higher gain in comparison with stacked solution. Finally we combined both techniques yielding the stacked 4×1 series feed antenna array. Fabricated CPW-fed antenna and the achieved results demonstrate the performance of presented techniques for gain improvements

Sensor Node Network for Remote Moisture Measurement in Timber Based on Bluetooth Low Energy and Web-Based Monitoring System

This paper proposes an IoT system based on wireless BLE connectivity to monitor the moisture content of wood, using a compact and low-cost moisture device that relies on a resistance measurement method valid for an ultra-wide range of resistance values. This device is digitally controlled with a BLE-incorporated micro-controller characterized by its small size and low power consumption, providing long-life battery. The proposed system consists of two main parts: first, the BLE moisture device including the moisture content measurement and wireless capability (BLE); second, the cloud-based monitoring platform, providing remote visualization and control for all the sensor nodes of the network. The complete infrastructure shows how multiple nodes can read and transmit moisture content of timber in buildings using small and unattended devices, with data saved in a central database and monitored by multiple commercial devices such as PC, smartphone, tablet, etc. The proposed system is innovative, scalable and low cost, and it can be deployed in wooden buildings and the wood industry, providing a practical solution that will help to avoid rot and other damaging effects caused by the moisture content

Gain Flatness and Noise Figure Optimization of C-Band EDFA in 16-channels WDM System using FBG and GFF

In this paper, Gain Flatness and Noise Figure of Erbium Doped Fiber Amplifier (EDFA) have been investigated in 16-channels Wavelength Division Multiplexing (WDM). Fiber Bragg Grating (FBG) is used in C-band with the aim to achieve flat EDFA output gain. The proposed model has been studied in detail to evaluate and to enhance the performance of the transmission system in terms of gain, noise figure and eye diagram of the received signals. To that end, various design parameters have been investigated and optimized, such as frequency spacing, EDF length and temperature. To enhance the transmission system performance in terms of gain flatness, the Gain Flattening Filter (GFF) has been introduced in the design. To prove the efficiency of the new design, the optical transmission system with optimized design parameters has been compared with a previous works in the literature. The simulation results show satisfactory performance with quasi-equalized gain for each channel of the WDM transmission system

Chromatic Dispersion Compensation Effect Performance Enhancements Using FBG and EDFA-Wavelength Division Multiplexing Optical Transmission System

An optical transmission system using Fiber Bragg Grating (FBG) and Erbium Doped Fiber Amplifier (EDFA) with new proposed model has been analyzed to overcome chromatic dispersion and attenuation phenomena. To evaluate the transmission system performance of the received signals, a simple model of one channel transmission has been developed in the first step. Also, optical fiber length and attenuation coefficient parameters have been investigated in detail to deal with the optimized corresponding parameter values. Results show that the performance of the optimized design parameters is very efficient in terms of output power (dBm), noise figure (dB), gain (dB), and Q-Factor. The model of one channel developed previously has been adapted to a complex model of four optical channels multiplexing with different wavelengths. FBG and EDFA have been also added to WDM technology system to enhance the chromatic dispersion and the signal attenuation. Results show that the new model is more efficient in terms of Q-Factor and eye diagrams