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

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.

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

Advanced Electromagnetics ◽

10.7716/aem.v9i1.1333 ◽

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.

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Design and Implementation of an Efficient Parallel LFSR Architecture for Wireless Communication Systems

Current Signal Transduction Therapy ◽

10.2174/1574362414666191016155707 ◽

2019 ◽

Vol 14 ◽

Author(s):

A. Suresh Babu ◽

B. Anand

Keyword(s):

Wireless Communication ◽

Power Consumption ◽

Low Power ◽

Communication Systems ◽

High Speed ◽

Design Tool ◽

Shift Register ◽

Linear Feedback ◽

Wireless Communication Systems ◽

Coverage Area

: A Linear Feedback Shift Register (LFSR) considers a linear function typically an XOR operation of the previous state as an input to the current state. This paper describes in detail the recent Wireless Communication Systems (WCS) and techniques related to LFSR. Cryptographic methods and reconfigurable computing are two different applications used in the proposed shift register with improved speed and decreased power consumption. Comparing with the existing individual applications, the proposed shift register obtained >15 to <=45% of decreased power consumption with 30% of reduced coverage area. Hence this proposed low power high speed LFSR design suits for various low power high speed applications, for example wireless communication. The entire design architecture is simulated and verified in VHDL language. To synthesis a standard cell library of 0.7um CMOS is used. A custom design tool has been developed for measuring the power. From the results, it is obtained that the cryptographic efficiency is improved regarding time and complexity comparing with the existing algorithms. Hence, the proposed LFSR architecture can be used for any wireless applications due to parallel processing, multiple access and cryptographic methods.

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A 90 nm based CMOS biquad Low pass filter for 3 KHz wireless applications with 23.6 dB gain and low power

Journal of Physics Conference Series ◽

10.1088/1742-6596/1706/1/012062 ◽

2020 ◽

Vol 1706 ◽

pp. 012062

Author(s):

T Muruganantham ◽

G Mohan ◽

M Maheswari

Keyword(s):

Low Power ◽

Pass Filter ◽

Low Pass Filter ◽

Wireless Applications ◽

Low Pass

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

Electronics ◽

10.3390/electronics10050632 ◽

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.

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The Research on the Police Adaptive Wireless Communications

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.850-851.549 ◽

2013 ◽

Vol 850-851 ◽

pp. 549-552

Author(s):

Chuan Sheng Zhao

Keyword(s):

Wireless Communications ◽

Wireless Communication ◽

Channel Model ◽

Model Simulation ◽

Excellent Performance ◽

Adaptive Equalizers ◽

Time Invariant

Most Current researches about the police adaptive wireless communication are concentrated on the area of the time-invariant channel model, which is not fit to the requirement of police application. This paper designed an time-variant ISI channel model, according to the characteristics of police wireless communication. And analyzed the performance of the LMS and the RLS algorithms in DFE structure adaptive equalizers, under the time-variant ISI channel model. Simulation shows that the designed adaptive equalizers obtained excellent performance.

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Impact of Various Parameters on the Performance of Inter-aircraft Optical Wireless Communication Link

Journal of Optical Communications ◽

10.1515/joc-2016-0112 ◽

2017 ◽

Vol 39 (1) ◽

Author(s):

Mehtab Singh

Keyword(s):

Wireless Communication ◽

Transmission Rate ◽

Power Level ◽

Communication Link ◽

Optical Wireless Communication ◽

Optical Wireless ◽

Antenna Aperture ◽

Aperture Diameter ◽

Pointing Error ◽

The Impact

AbstractOptical wireless communication (OWC) systems also known as Free space optics (FSO) are capable of providing high channel bandwidth, high data transmission rates, low power consumption, and high security. OWC links are being considered in different applications such as inter-satellite links, terrestrial links, and inter-aircraft communication links. This paper investigates the impact of different system parameters such as transmission power level, operating wavelength, transmitter pointing error angle, bit transmission rate, atmospheric attenuation, antenna aperture diameter, geometric losses, the responsivity of the photodetector, and link range on the performance of inter-aircraft optical wireless communication link.

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