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Development of WLAN Topology Display System
(2023-01-01)
Wongwirat, Olarn
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Chotiphan, Supannada
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Hongtong, Tadchapon
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Suttijumnong, Nattawat
Currently, packet sniffer tools can capture packets and provide information for monitoring, analyzing, and troubleshooting networks, e.g., traffic, bandwidth, protocol, etc. However, these tools lack the capability, or feature, to display a network topology diagram on the screen, particularly for a WLAN (Wireless Local Area Network), which is different from expensive network monitoring software sold commercially in the market. Therefore, it is difficult for a network administrator to visualize which client is connected to which AP (Access point) in the service areas of WLAN, or hotspots, for monitoring. This paper presents the development of the WLAN topology display system to support the network administrator in monitoring and enhancing the network services in the future. The system acquires the packet data captured by the packet sniffer tool, i.e., Wireshark. Then, the packet information is analyzed by using the data from the MAC (Medium Access Control) header following the IEEE802.11 standard to find the types, connection modes, and MAC addresses. Finally, the mapping table associated with the connected devices, i.e., client stations and APs, is constructed and used to create the WLAN topology diagram to display on the screen. The prototype system is implemented and tested in the laboratory environment, and the WLAN topology diagram showing the connections between the clients and the APs can be displayed on screen accurately as required.
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Investigation of received signal strength of IEEE 802.11n WLAN in coverage of nakhon Ratchasima Rajabhat University
(2018-07-02)
Nakprasit, Krittaya
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Phongcharoenpanich, Chuwong
Wireless networks (WLAN) of IEEE 802.11n standards are being deployed in increasing numbers. The applications require high bandwidth so WLAN will be provided the high data rate over coverage area. The enhancements of WLAN bring to network engineers having significant problems of installing the access point. Prior to the installation of access points, it is difficult to predict access can be guaranteed at specific locations or not. To guarantee high data rate and quality of service, site survey of WLAN in Nakhon Ratchasima Rajabhat University (NRRU) is required. The importance parameter related to data rate and quality of service is Received Signal Strength Indicator (RSSI). WLAN investigation of received signal strength was measured inside indoor environment by using 3 programs: InSSIDer, Xirrus Wi-Fi Inspector and WirelessMon Professional. In this paper, free space loss equation with and without antenna gain can be simply applied to predict RSSI. This work is useful for WLAN planning of future NRRU.
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WLAN Localization Measurement and Analysis Using RSS and TOA Positioning Methods
(2018-07-02)
Lorvannger, Khounhack
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Lakanchanh, Donekeo
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Tiengthong, Thanadol
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Promwong, Sathaporn
Wireless local area network (WLAN) has been exclusively research due to its widely used applications. Its operate frequency spectrum is in the ISM band and regulated in IEEE 802.11 family. Localization is one of the application which able to used WLAN signal. Its can be used in various applications such as logistics, security, disaster rescue operation tracking, and military service. Since the various kind of its applications is work in indoor environment, the indoor localization requires high accuracy. The receive signal strength (RSS) and time of arrival (TOA) are a parameter that used in the comparison between min-max technique and trilateration technique in this paper. In the measurement of this research, the frequency bandwidth is ranging from 2.3 GHz to 2.5 GHz, an access point is used to represent both of transmit antenna and receive antenna. The cumulative distribution function (CDF) is used for study the most accuracy.
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A comparison of decision tree based techniques for indoor positioning system
(2018-04-19)
Chanama, Lummanee
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Wongwirat, Olarn
Currently, an indoor positioning system based on a fingerprint technique for wireless networks under IEEE 802.11 standard uses a method to collect a received signal strengths (RSS) to create a radio map in an offline phase. Then, it detects the RSS in an online phase to compare and find the position. However, while detecting and gathering the RSS, there are some variations of the RSS that affect the accuracy of position estimation. Therefore, there are several methods used to estimate the position in order to improve the accuracy, but the one focused in this paper is a decision tree based classification. The decision tree based classification method is found that it can provide better improvement in accuracy than the others, e.g., K-Nearest Neighbor (K-NN), Bayesian, and Neural networks. However, the techniques used to construct the decision tree are varied depending on the algorithm used to implement. Therefore, this paper is a comparison of decision tree based techniques using typical decision tree (DT) and Gradient boosted tree algorithms for estimating the position indoor. In the study, the RSSs collected from access points in the experimental area are used as the training and testing data. The decision tree models are created by using typical DT and Gradient boosted algorithms based on the training data obtained. There are two factors to consider in the comparative study, i.e., the number of training data and the number of reference radio signals. The testing results from the experiment showed that the decision tree based on Gradient boosted algorithm yielded more accurate results than typical DT, where the amount of 19 reference radio signals and 50 samples of training data gave the best result.
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Rogue access point detection mechanism considering sequence number of beacon frame for wireless local area networks
(2017-11-03)
Ketkhaw, Apisak
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Thipchaksurat, Sakchai
Rogue Access Point (RAP) is one of the serious problem concerned with the security issues. The attacker usually inserts the RAP by setting the information such as Service set identifier (SSID), MAC Address and beacon frame size same as those of the legitimate AP. In this paper, we propose the mechanism for RAP Detection by considering sequence number of beacon frame in wireless local area networks (WLAN). Our proposed mechanism considers sequence number of beacon frame by introducing checking detection window technique for detecting the RAP. We show the effectiveness of mechanism by conducting an experiment. The results show the our proposed mechanism is able to detect RAP accurately.
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A triple-band printed microwave absorber for WLAN/WiMAX applications
(2017-10-19)
Khoomwong, E.
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Soemphol, C.
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Phongcharoenpanich, C.
This paper presents a triple-band printed-circuitboard microwave absorber for applications in 2.4GHz WLAN and 3.5/5.8GHz WiMAX bands. The absorber consists of simple geometries with tuning elements and chamfering, which can significantly reduce the modeling errors. The study and design processes are based on numerical simulations. The simulated results show the absorption bandwidths (at 50%) of 160MHz (2.36-2.52GHz), 160MHz (3.48-3.64GHz) and 520MHz (5.54- 6.06GHz). The absorptions at the center frequency of each band (i.e. 2.45, 3.55 and 5.78GHz) are also found feasible at 97.6%, 85.2% and 96.0%, respectively. From the study, the proposed absorber is applicable for a fairly wide-Angle of wave incidence and suitable for a number of applications in the specified bands. The main advantages of the proposed absorber are thin, simple and low-cost structure, which can be very useful for various applications in WLAN and WiMAX bands.
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Performance of textile antenna using two layers of strip line and round-off circular patch
(2016-03-07)
Chaihongsa, Warangkana
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Phongcharoenpanich, Chuwong
In this paper, a dual band textile antenna operable at 2.4/5.2 GHz for WLAN application has been presented. The wearable 1 mm thick felt fabric having relative permittivity of 1.90 and loss tangent of 0.016 has been used as substrate material. The return loss, radiation pattern and realized gain measurements are used to characterize a prototype using vector network analyzer and anechoic chamber. The |S11| is lower than-10 dB covered the frequency band from 2.16 GHz to 2.63 GHz and from 4.45 GHz to 5.90 GHz. The gains at two bands are 1.8 dBi and 3.2 dBi, respectively. This antenna yields omnidirectional pattern. The simulation and measurement results are in good agreement. Additional, the effects on the return loss for the antenna under the bent conditions are further discussed.
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Design of triple-band antenna using S-shaped patch fed by cross strip line for WLAN and WiMAX applications
(2015-09-01)
Chawanonphithak, Yuktitath
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Phongcharoenpanich, Chuwong
This paper presents a simple triple-band S-shaped patch antenna fed by a cross strip line for both WLAN and WiMAX applications. It is operated at the triple bands of 2.4 and 5.2 GHz for WLAN and 3.5 GHz for WiMAX. The antenna, designed on an FR4 substrate with a thickness of 1.6 mm and relative permittivity of 4.4, is fed by a 50-Ω microstrip line, and is of size 25 × 35 mm. The simulated and measured results of |S<inf>11</inf>|, gains, and radiation patterns are presented. The measured results show that the triple-band antenna achieves a broad operating bandwidth of 2.36-2.54, 3.27-3.69, and 5.16-5.48 GHz for a 10-dB return loss (i.e. |S<inf>11</inf>|<-10 dB). The gains of the antenna measured at 2.4, 3.5, and 5.2 GHz frequencies are 1.87, 1.95, and 3.82, respectively. The radiation pattern of the antenna is omnidirectional.
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Ultra-wideband slot antenna on flexible substrate for WLAN/WiMAX/UWB Applications
(2014-01-01)
Archevapanich, Tuanjai
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Lertwatechakul, Mayuree
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Rakluea, Paitoon
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Anantrasirichai, Noppin
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Chutchavong, Vanvisa
An ultra-wideband slot antenna on flexible substrate is designed to support a wide range of wireless communication systems. The antenna is a rectangular slot antenna fed by microstrip line with conductor strip and tuning stub on flexible substrate (Mylar Polyester film). The rectangular slot is etched out from the ground plane with conductor strip in the slot, and the other plane contains a microstrip line with tuning stub. The proposed antenna’s effective frequency range covers overall standard bands of WLAN, WiMAX, and UWB. The antenna was simulated and analyzed by using IE3D Zeland software [1]. And the simulation results presents the characteristics of the antenna in terms of bandwidth return loss, VSWR, and radiation patterns.
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Binary Exponential Increment Half Decrement backoff algorithm for IEEE802.11 wireless LANs
(2013-09-02)
Sartthong, Jesada
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Sittichivapak, Suvepon
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Kaewpukdee, Adisorn
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Boonpikum, Ittibhoom
Backoff algorithm is a technique to reduce packet collisions and to improve throughput efficiency in wireless local area network (WLAN). In this research, we propose a new backoff algorithm which is named Binary Exponential Increment Half Decrement (BEIHD) backoff algorithm. Furthermore, we introduce a new discrete Markov chain model for modeling the performance analysis of wireless local area network. A new model is called the Fixed Backoff stages and Fixed Contention windows (FBFC) technique. In FBFC scheme, the accuracy of the transmission probability parameter is derived from step by step procedure using the global balance equation concept in steady state condition. The saturated throughput efficiency of all backoff algorithms is compared under the same Physical layer (PHY) parameters and Medium Access Control (MAC) scheme in IEEE802.11a/b/g standards. Our numerical results show that the throughput performance of BEIHD backoff algorithm is better than the Binary Exponential Backoff (BEB) algorithm. Moreover, the distinction of BEIHD backoff algorithm is near the realistic system, and it can be implemented without to modify hardware in physical layer. © 2013 IEEE.

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