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Comparison of path loss prediction models for UAV and IoT air-to-ground communication system in rural precision farming environment
(2021-02-01)
Duangsuwan, Sarun
;
Maw, Myo Myint
The comparison of path loss model for the unmanned aerial vehicle (UAV) and Internet of Things (IoT) air-to-ground communication system was proposed for rural precision farming. Due to the uncertainty of propagation channel in rural precision farming environment, the comparison of path loss prediction was investigated by the conventional particle swarm optimization (PSO) algorithms: PSO (exponential or Exp), PSO (polynomial or Poly) and the machine learning algorithms: k-nearest neighbor (k-NN), and random forest, are exploited to accurate the path loss models on the basic of the measured dataset. Meanwhile, the empirical model in the rural precision farming was considered. By using the machine learning-based algorithms, the coefficient of determination (R-squared: R<sup>2</sup>) and root mean squared error (RMSE) were evaluated as highly accuracy and precision more than the conventional PSO algorithms. According to the results, the random forest method was able to perform more than other methods. It has the smallest prediction errors.
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Comparative analysis of radio propagation models for LTE network on the sky train
(2019-04-29)
Dataesatu, Arif
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Boonsrimuang, Pornpawit
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Mori, Kazuo
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Boonsrimuang, Pisit
The usage of smartphones and computer for the data communications have become a more integrated part of everyday life for a large majority of the population. One important mode of transportation is the sky train, and users increasingly expect to be able to communicate satisfyingly while traveling on the train: MRT (Mass Rapid Transit Authority of Thailand). However, the radio conditions inside a train are very complex. A possibly large number of users that use at the same time, moving at high speed and a special environment on elevated guideways (height 20 m) are created big challenges for the data communication in LTE network. The accuracy of the path loss model is a very important tool to design the coverage areas and improve the performance in LTE network. This paper that studies and improve the accuracy of the path loss model, which use to design the coverage area of the LTE network under the sky train environment. Normally the radio propagation models under the urban area are designed on the ground approximately 1-3 meters in height but are not suitable for the user in the sky train, which is 20 meters high. we propose the Ericsson urban model in the special environment as sky train by the new values for a0 from 36.2 to 47.2 and a1 from 30.2 to 14.2. The proposed new coefficient for Ericsson urban model shows the most accurate path loss under the sky train with the urban area. The filed measurement is used by the smartphone-based measurement for low cost and practical usage.
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Body area network transfer function measurement with frequency band from 3 GHz to 9 GHz
(2019-04-15)
Chaisang, Aditep
;
Promwong, Sathaporn
Wireless technology for body area network (BAN) is significant interesting in the modern development of short range wireless communication network. Impulse characterization of ultra-wideband is important parameter that used to study in order to understand a signal propagation of BAN channel. Since the complexity of wireless human body applications are higher than another application. Anyway, it is important to understand the channel distribution characteristics due to human body effect. In this research report, transfer function of BAN channel at frequency 3-9 GHz have been presented as the characteristics of waveform transmission in case of with and without human body for apply to the development of short range wireless applications based on the measurement data of this report. To obtain the maximum value of signal to noise ratio (SNR), the matched filter was used as the optimum receiver for better signal quality and well evaluation of BAN system. The transmission equation of Friis was introduce to evaluate the measurement results in this report. The proposed method provides a higher precision and useful for the analysis and design of BAN channel to apply with the system of wireless medical system which focusing on the distortion of transmission signal.
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An Investigation of UWB Path Loss for Body Area Network
(2018-12-24)
Sansoda, Buncha
;
Choomchuay, Somsak
This paper presents the investigation of body area communication channel and provide path loss evaluation by measurement compared with channel model of IEEE 802.15.6 standard. The measurement performs in ultra-wideband frequency range and setup the body in different body poster. The receive antenna is mounted on waist while transmit antenna is placed on wrist and ankle. We found trend of path loss similar as model. The results shows that transmission between the two antenna are highly attenuated when the radio wave propagates across the body. However, if the wave direction propagates along the body as waist to ankle, the path loss would slowly increase. Thus the suitable position of antenna would certainly be important with measurement result to reduce the body effect.
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Minimizing path loss prediction error using k-means clustering and fuzzy logic
(2018-01-01)
Wiyada, Bhupuak
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Siraphop, Tooprakai
This research proposes an algorithmic scheme based on k-means clustering and fuzzy logic to minimize path loss prediction error. The proposed k-means fuzzy scheme concurrently utilizes the area topographical variability and multiple path loss prediction models to mitigate the prediction error inherent in the independent use of a conventional path loss model. Vegetation density, manmade structures, and transmission-receiver distances are the fuzzy inputs and the conventional path loss models the output: the free space loss, Walfisch–Ikegami, HATA, ECC-33, Stanford University Interim, and ERICSSON models. The experimental results show that the path loss prediction error of the k-mean fuzzy scheme is only 2.67% compared to the the drive-test measurement, and this is the lowest relative to that of the conventional models. The k-mean fuzzy scheme offers a novel means to approximate path loss in localities with diverse topographical features and also efficiently mitigates the prediction error inherent in the independent use of the conventional prediction models.
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Path loss comparison in 850 MHz and 1800 MHz frequency bands
(2016-09-06)
Bhupuak, Wiyada
;
Tooprakai, Siraphop
Nowadays people widely used mobile phone instead of using landlines phones. This paper proposes to compare the path loss in 850 MHz and 1800 MHz frequency bands by various path loss models. The path loss under terms of the transmitter height and the receiver height. The well known path loss model such as Walfisch-Ikegami (WI), SUI and Ericsson model used to simulate path loss by MATLAB. The results shown that when the longest distance WI model has the most path loss at the receiving antenna height is 1 and 5 meters. The path loss in the frequency bands 1800 MHz is greater than the path loss in the frequency bands 850 MHz under the same conditions. The path loss can be use to determine where to install the mobile base station with high quality. That means at the same distance if using the frequency band 1800 MHz for mobile network in the same technology will require to install the mobiles base station more than using frequency band 800 MHz.
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Characteristic of ultra wideband body area network channel
(2015-10-01)
Teawchim, Sanit
;
Promwong, Sathaporn
This paper presents characteristic of ultra wideband body area network (UWB-BAN) channel. The passband rectangular waveform and passband root raised cosine (RRC) waveform are provided to transmit signal. In this paper, an investigation channel measured by using a network analyzer and performed a frequency ranged with 3 GHz–5 GHz. The meander line miniature antennas were taken to obtain as a transmitter and receiver antenna side, repectively. The 12 sample bodies with 10 positions of each body were considered. The linear regression model of large-scale path loss and cumulative distribution function (PDF) of multipath fading factor based on average and peak power loss are shown. Measurement data are useful to predict the performance of UWB-BAN system.
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Ground reflection path loss based on average power loss for ultra wideband communications
(2007-12-01)
Supanakoon, Pichaya
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Kaewsirisin, Sarunya
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Promwong, Sathapom
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Noppanakeepong, Suthichai
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Takada, Jun Ichi
In this paper, the ground reflection path loss based on average power loss for ultra wideband (UWB) communications is proposed. The expression is derived from the rectangular passband waveform and extension of Friis" transmission formula in the terms of the closed form formula based on average power loss. The results are compared with other models and verified with the measurement result. From the results, this proposed model corresponds with compared models and measurement result.
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Indoor measurement results of UWB impulse radio for shot-range wireless systems with RMS delay spread and path loss
(2005-12-01)
Leechaikitjaroen, Keatichai
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Promwong, Sathaporn
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Supanakoon, Pichaya
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Chensirikul, Somsak
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Kaewmechai, Sompoph
In this paper, we describe a simple method for measurement of the ultra-wideband (UWB) frequency response for evaluation of the path loss and RMS delay spread which are the important parameters for the wireless communications, probability and cumulative density of rms delay spread and path loss are evaluated based on the measurement of UWB indoor environment. For the measurement, the frequency responses of the UWB channel are acquired by using a vector network analyzer (VNA) over the frequency bandwidth of 3-11 GHz. The biconical antennas are used for both the transmitter (Tx) and receiver (Rx) antennas. The probability density function and cumulative distribution function of the rms delay spread and path loss are shown. The results are discussed in this paper. © 2005 IEEE.
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Analysis of probe excited circular ring above reflector in outdoor WLAN systems
(2005-12-01)
Phongcharoenpanich, Chuwong
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Chawanonphithak, Yuktitath
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Wounchoum, Phairote
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Krairiksh, Monai
This paper presents the analysis of probe excited circular ring above reflector in WLAN bridge systems. The evaluation performance mainly in terms of link distance, compared probe excited circular ring above reflector and monopole antenna. The path loss used to determine service range is modelled by two-ray model. The calculation and experimental results are very useful for design and evaluation performance of WLAN bridge systems. ©2005 IEEE.

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