Investigations of Foliage Effect on Modern Wireless Communication Systems: A Review

The range measurement is the premise for location, and the precise range measurement is the assurance of accurate location. Hence, it is essential to know the accurate internode distance. It is noted that the path loss model plays an important role in improving the quality and reliability of ranging accuracy. Therefore, it is necessary to investigate the path loss model in actual propagation environment. Through the analysis of experiments performed at the wheat field, we find that the best fitted parametric exponential decay model (OFPEDM) can achieve a higher distance estimation accuracy and adaptability to environment variations in comparison to the traditional path loss models. Based on the proposed OFPEDM, we perform the RSSI-based location experiments in wheat field. Through simulating the location characteristics in MATLAB, we find that for all the unknown nodes, the location errors range from 0.0004 m to 5.1739 m. The location error in this RSSI-based location algorithm is acceptable in the wide areas such as wheat field. The findings in this research may provide reference for location estimation in large-scale farmland.

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“…The Weissberger model is applicable for the frequency ranging from 230 MHz to 35 GHz. The ITU-R model can be defined as follows [38]:…”

Section: Rssi-based Location Methodsmentioning

confidence: 99%

The Accurate Location Estimation of Sensor Node Using Received Signal Strength Measurements in Large-Scale Farmland

Miao

Zhang

2018

Journal of Sensors

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“…However, because of the small transmitted power from wireless sensor nodes, most scattered or diffused components are very weak. Nonetheless, their presence is illustrated by the reduction in the signal decay gradient at distances further from the transmitter [16]. The generalized form of the MED vegetation attenuation models is given by:…”

Section: The Regression Analysis For Path Lossmentioning

confidence: 99%

“…( ) r t P P PL According to the previous studies [15,16], there are many vegetation attenuation models, such as Non-zero Gradient model and Modified Exponential Decay (MED) model. From a propagation mechanisms perspective, at very shallow vegetation depths, signal propagation is dominated by coherent components which decrease rapidly with distance [15].…”

Section: The Regression Analysis For Path Lossmentioning

confidence: 99%

The Irregularity Propagation Characteristics of Radio Signals For Wireless Sensor Network In Farmland

Zhu

Zhang

et al. 2016

ITM Web Conf.

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Abstract. This work aims to investigate the irregular propagation characteristics of wireless sensor network (WSN) at frequency of 433 MHz. Through the analysis of the received signal strength indicator (RSSI), it is found that the variance in received signal strength is largely random, along with a continuous change with incremental changes in direction. For the transceiver distance is 20 m, the packet loss rate (PLR) in all directions is relatively small except for the east direction, indicating that the signal is still strong in all directions. While for the transceiver distance is 40 m, it can be found that there is about 90% packet loss in the east direction. That is, the received signal strength in the east direction is lower than that in the other directions. Moreover, the communication range varies with the degree of receiver direction ranging from 0 to 359. Through the regression analysis in Matlab, we find that the optimal fitting models in different directions are different. The optimal fitting model in east and west direction is the modified exponential decay, and in south and north direction is the linear logarithmic model. The values of R 2 vary from 0.935 to 0.961, and the values of RMSE range from 1.75 to 2.31.

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“…If the height of the receiving antenna, h , is sufficiently high, ground-reflected wave can be ignored. Therefore, the maximum transmitted power, P T,max , can be obtained by the Friis transmission equation and LOS conditions [11,12]:…”

Section: Maximum Eirp Estimationmentioning

confidence: 99%

Maximum Eirp and Emf Estimation Based on Over-the-Air Measurements of Wcdma Pilot Channel

Jang¹,

Moon²,

Yoon³

2012

PIER C

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Abstract-This paper presented an estimation method of maximum effective isotropic radiated power (EIRP) and electro-magnetic field (EMF) strength of a wideband code-division multiple-access (WCDMA) base station based on over-the-air measurements of a pilot channel in a code domain. To verify the feasibility of the proposed method, we estimated the maximum EIRP and EMF strengths of the self-designed test base station, and compared them with EIRP and EMF values measured by the traditional test scheme. Then, we applied our estimation scheme to the inspection test for a commercial base station. The maximum difference between the estimated EIRP values from our method and the reported values is 1.3 dB. The estimated EMF results show more than 90% agreement with both the traditional EMF measurement value under a full-traffic load condition and the theoretical value. Therefore, it can be concluded that our proposed estimation method should be an effective inspection test for domestic base stations.

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Investigations of Foliage Effect on Modern Wireless Communication Systems: A Review

Cited by 99 publications

References 53 publications

The Accurate Location Estimation of Sensor Node Using Received Signal Strength Measurements in Large-Scale Farmland

The Accurate Location Estimation of Sensor Node Using Received Signal Strength Measurements in Large-Scale Farmland

The Irregularity Propagation Characteristics of Radio Signals For Wireless Sensor Network In Farmland

Maximum Eirp and Emf Estimation Based on Over-the-Air Measurements of Wcdma Pilot Channel

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