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Indoor wireless sensor network localization using RSSI based weighting algorithm method
(2020-07-01)
Sangthong, Jirapat
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Thongkam, Jutamas
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Promwong, Sathapom
Now a day, appropriate and correct indoor positioning in wireless networks could provide interesting services and applications. However, there are more factors of the indoor environment caused to reduce the precise localization and also increase the error of distance. This paper presents a new method to evaluate the wireless sensor network (WSN) technology for the indoor localization. The weighting algorithms: the weight range localizer (WRL) and relative span exponential weight range localizer (RS-WRL) are using based on received signal strength indicator (RSSI) to estimate the position of target node. As the results, the cumulative distribution function (CDF) probability indicates the error of distance as properly, and this method can help to increase the precision of range based localization method in an application of indoor environment.
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Evaluation of UWB antennas at 7-9 GHz for short range wireless communications
(2018-06-08)
Chinabutr, Chatchawin
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Promwong, Sathapom
Ultra wideband (UWB) impulse radio (IR) signals must be able to accomodate its common frequency band at 7.25 GHz to 8.50 GHz. Moreover, the signals should not be distorted too much when they pass through the antennas. Therefore, the transfer function of antennas must to known for the channel performance. In free space loss is usually evaluated by using the formula of Friis's. However, Friis's formula it's not directly applicable to UWB-IR transmission. This study to presentation, the characterization of UWB-IR transmission in FCC with common frequency band that takes into account the transmission waveform in UWB, its consider the distortion due to the antennas and the correlator receiver. Since the antennas are significant pulse-shaping filters in UWB, various kinds of antennas are experimentally examined, especially focusing on the effect of template waveform receiver.
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Body area network measurement with ultra wideband technology
(2011-12-01)
Arpasin, Dissakan
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Noitubtim, Musleemin
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Manositthichai, Narongsak
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Promwong, Sathapom
Presently the communications technology is much progress and devices are likely to be used on body network. Education has been thought. This project studies patterns of ultra wideband for a broadband network on the body network. It is high speed data technology for study the impact of the human body. The vector network analyzer is used to measure and record the results. Those results are process by using a Friis's formula to be theory form. Such as Bit error rate and receive signal. This study design model for measure and test the actual experiment on the human body in the room of building. Usefulness of information that can be measured has created a communications network on the human body using ultra wide band technology. © 2011 IEEE.
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Evaluation of ultra wideband impulse radio transmission loss due to laptop computer
(2009-12-01)
Sereewattanapong, Thawatchai
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Promwong, Sathapom
This paper presents the evaluation of the transmission gain of an ultra wideband antenna on a labtop computer based on the extended Friis' transmission formula. The matched filter is considered at the receiver side to maximize the SNR for evaluation. This technique gives very accurate results and is very useful for the design and evaluation of UWB impulse radio transmission systems, especially for the evaluation of waveform distortion effects. ©2009 IEEE.
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Free space SNR gain and transmission gain of ultra wideband template receiver for WPAN
(2009-01-01)
Promwong, Sathapom
In this paper, we evaluated the signal to noise ratio (SNR) gain and transmission gain of ultra wideband (UWB) receivers performance for wireless personal area network. The optimum and isotropic template receivers are considered based on the data measurement. The biconical antennas are used as the transmitter (Tx) and receiver (Rx) antennas. The rectangular passband, which is satisfied the full band of UWB signal definition and Federal Communications Commission (FCC) indoor and outdoor limit spectral masks, is used as the transmitted UWB signal. The channels are measured in an anechoic chamber by using a vector network analyzer (VNA). The SNR gains and transmission gain of optimum and isotropic template receivers are shown and compared in results.
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Waveform distortion analysis on transmission gain and group delay of ultra wideband impulse radio
(2009-01-01)
Promwong, Sathapom
In this paper, we evaluated of ultra wideband impulse radio transmission gain and group delay by using the Friis' transmission formula. However, this formula is not directly applicable to ultra wideband impulse radio transmission systems. This paper presents the free space link evaluation formula in the term of transmission gain for the ultra wideband impulse radio systems that takes into account the transmitted waveform, its distortion due to the antenna, the channel and the correlation receiver. Since the antennas are significant pulse-shaping filters in ultra wideband impulse radio, the antenna are experimentally examined, especially focused on the effect of the received signal and the isotropic template waveforms.
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Ultra wideband propagation channel on two path model with laptop computers
(2009-01-01)
Manositthichai, Narongsak
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Promwong, Sathapom
This paper presents the ultra wideband propagation (UWB) channel on two path model with laptop computers. The UWB pulse with specific center frequency and bandwidth is used for transmitted signal. Complex form Friis' transmission formula is applied for the UWB propagation channel. The received signal is evaluated. The UWB path loss is defined as the ratio between the maximum amplitude of the transmitted and received signal waveforms. For the data processing, the path loss of two path model is considered for the 0.10 and 0.20 m antenna heights. The double linear regression for the path loss is modeled by using the minimum mean square error (MMSE) and first Fresnel zone break-point curve fits. The characteristics of the path loss function of the antenna heights are evaluated and discussed in this paper.
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Experimental evaluation of transmission channels with various ultra wideband antennas
(2008-12-01)
Promwong, Sathapom
In this paper, we evaluated of the free space transfer function in ultra wideband impulse radio (UWB-IR) transmission channels with various ultra wideband antennas by using the Friis' transmission formula. However, it is not directly applicable to UWB-IR transmission systems. This paper presents the transfer function link evaluation formula in the term of transmission channel for the UWB systems that takes into account the transmitted waveform, its distortion due to the antennas, the channel and the correlation receiver. Since the antennas are significant pulseshaping filters in UWB impulse radio, the various kinds of the antennas are experimentally examined, especially focused on the effect of the received signal. © 2008 IEEE.
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Experimental study of ultra wideband antenna performance with laptop computers
(2008-12-01)
Manositthichai, Narongsak
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Promwong, Sathapom
The experimental study of the ultra wideband (UWB) antenna performance with laptop computers in an indoor channel are analyzed at 3.1 GHz to 10.6 GHz frequency band. The characteristics of indoor propagation channel are very complicated and difficult to predict. Therefore, the performances of UWB antenna signal shall be considered. This paper present the UWB antenna performance. The rectangular passband waveform, which satified the Federal Communication Commission (FCC) definition of UWB signal and FCC spectral masks for the indoor limits, are considered. In addition, we considered the matched filter for the receiver side to maximize the signal to noise ratio (SNR). The UWB antenna transfer function, the UWB signal waveform of the UWB systems are evaluated. The transmission gain, the correlation coefficient are presented and discussed. © 2008 IEEE.
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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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