Supanakoon, Pichaya
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Supanakoon, Pichaya
Alternative Name
Supanakoon, P.
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Email
pichaya.su@kmitl.ac.th
15 results
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Item type:Publication, Comparison of UWB fingerprinting with vertical and horizontal polarizations for indoor localization(2010-07-30); The indoor localization system has been extensively researched because of its various applications. This system requires high accuracy in indoor environments which absence line of sight and dense multipath. Ultra wideband (UWB) fingerprinting is developed for this purpose. This paper discuss about indoor localization using a fingerprinting concept based on UWB signal and compares between vertical and horizontal polarization cases. All of the measurements used biconical antennas as both transmitter (Tx) and receiver (Rx) antennas. The channel frequency transfer functions of corridor environment were measured at frequencies ranging from 3 GHz to 11 GHz. The path loss and delay time of first three-path is investigated to perform the fingerprints and signatures. The accuracy of estimated distances is shown in terms of cumulative distribution function (CDF). From the results, horizontal polarization provides greater accuracy than vertical polarization. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Measurement and evaluation of radar cross section for furniture in an indoor propagation channel(2014-11-11); ; Takada, J.This paper has attempted to evaluate the radar cross section (RCS) of two furniture items in an indoor environment in a frequency range of 3-7 GHz of the ultra-wideband (UWB) range. The RCS evaluation is achieved through an extended version of the radar equation that incorporates the channel transfer function of scattering. The time-gating method was applied to remove the multipath effect, a phenomenon which typically occurs in the indoor environment. Two double-ridged waveguide horn antennas for both vertical and horizontal polarizations were used to obtain the transfer function of scattering of the furniture prior to analysis in order to derive their bistatic RCS. The RCS results validate the applicability of the proposed extended radar equation to the indoor propagation prediction. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Quantitative Measurement of Path Loss Model Adaptation Using the Least Squares Method in an Urban DVB-T2 System(2018-01-01); ; The aim of this paper was to propose quantitative measurement of path loss model adaptation in urban radio propagation for a second-generation, terrestrial digital video broadcasting standard (DVB-T2) system. The measurement data was analyzed using data processing based on the least squares (LS) method to verify the probabilistic quantitation of realistic data measurement such as mean error (ME), root mean square error (RMSE), and standard deviation of error (SD), as well as relative error (RE). To distinguish the experimental evaluation, the researchers compared between the conventional Hata path loss model and the proposed model. The result showed that path loss based on the proposed model was more accurate in predicting the quantitative measurement of propagation data properly. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Performance Evaluation of Artificial Megneto-Dielectric Metamaterial with Microstrip Patch Antenna for Wireless System(2018-07-02); This paper we presents the performance evaluation of artificial magneto dielectric substrate with microstrip patch antenna for wireless system. From the result, at the resonance frequency 2.45 GHz have the radiation efficiency and the real gain are 88.87% and 6.89 dBi, respectively. The microstrip patch antenna on finite artificial magneto dielectric substrate by used metamaterial structure. The unit cell consist of multi square loop pinned in the dielectric material. The feature of the antenna can be rectify with controlling permeability (boldsymbolmu-eff) and permittivity (boldsymbolvarepsilon-eff). - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Waveform distortion and transmission gain on ultra wideband impulse radio(2010-01-01); ; Takada, Jun IchiA waveform of an ultra wideband impulse radio (UWBIR) system can be extremely distorted through a channel even for free-space transmission because of antenna dispersion. This highly degrades the link budget performance. Therefore, the understand of antenna characteristics, which effects on waveform distortion, is necessary. This paper studies the waveform distortion due to antenna in free space transmission in UWB-IR system. The link budget is usually evaluated by using the Friis' transmission formula. However, it is not directly applicable to the UWB-IR transmission system. The link budget evaluation formula attended from conventional Friis' transmission formula that takes into account the transmitted waveform, its distortion due to the antennas, the channel and the correlation receiver is proposed. Since the antenna is significant pulse-shaping filters in UWB-IR system, the example kind of the log-periodic dipole antenna (LPDA) is experimentally examined, especially focused on the effect of the template waveforms. Copyright © 2010 The Institute of Electronics, Information and Communication Engineers. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Study on performance of ultra wideband and narrow band propagation for an indoor positioning(2016-07-18); This paper studies ultra wideband (UWB) and narrow band (NB) propagation in the frequency range of 3 GHz to 11 GHz. The UWB signal was used to follow the standard of IEEE802.15.4a in order to find the position in line of sight (LOS) and non-line of sight (NLOS) environment. Then, the sinusoidal frequency was tested in the frequency range of 3 GHz to 11 GHz, changing 1 GHz per step in order to analyze and compare with the UWB standard. The experiments were done by using vector network analyzer (VNA). Four conditions were studied in LOS and NLOS environment for indoor positioning. The four condition are the parameters; UWB standard; polarizations; and the frequencies. For the positioning determination, a location pattern technique was used with a minimum root mean square (RMS) error matching algorithm to find the position. Finally, a suitable condition is shown, and it has an accuracy of 91.11% at 1 meter. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Measurement scheme of radar cross section with time gating(2017-11-03); This paper proposes measurement scheme of radar cross section (RCS). The measurement of quasi monostatic radar channel is done in anechoic chamber. The time gating technique is used for removing the effect of mutual coupling between transmitter (Tx) and receiver (Rx) antennas. The personal computer (PC) case is used as the target under test (TUT). The vector network analyzer (VNA) is used to measure transmission coefficient in frequency range covered ultra wideband (UWB) that is 3-11 GHz. The double-ridged waveguide horn antennas are used as Tx and Rx antennas with vertical polarization. The complex frequency transfer function at each angle is used to evaluate the RCS of TUT. The RCS with time gating are shown and compared with that without time gating. From the results, we can see that the proposed measurement scheme can be increased the accuracy of RCS that evaluated from quasi monostatic radar with dense mutual coupling between Tx and Rx antennas. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Evaluation scheme RFID channel in library with wooden and metal book shelves based on measurement data(2010-07-30); At the present time, radio frequency identification (RFID) library management system are applied in many libraries for convenience and more efficiency. Channel modeling is necessary for predicting received power and performance system. In this paper, the channel of wooden and metal book shelves are modeled for RFID library management system. The channels were measured at frequency of 2.45 GHz. The microstrip antennas were used as both transmitter (Tx) and receiver (Rx) antennas. Vertical-vertical (V-V) and horizontal-horizontal (H-H) polarizations are considered. Linear regression is used to model the path loss characteristic. After that, statistical models, cumulative distribution function (CDF), are used to characterize the multipath fading. From the results, we can conclude that the wooden book shelves of V-V polarization and metal book shelves of H-H polarization are appropriate to use for RFID library management system. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Study on RSRP of LTE Mobile Phone on Thailand's National Highway(2018-07-02); - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Hata's path loss model calibration for prediction DTTV propagation in urban area of southern Thailand(2015-01-01); This article presents Hata's path loss model calibration in order to predict a design of the Digital Terrestrial Television (DTTV) Propagation in an urban area of the south of Thailand through measuring power signal of the network operators' broadcasting in 4 channels within Haadyai urban area, Songkla Province. The chosen location is a density area, a distance of 2.5-6.5 km. from the broadcasting station. The calibration was conducted through a statistical method of Root Mean Square Error (RMSE) from received power signal and compared with a path loss model from the prediction, followed by looking for relative errors to indicate the efficiency of the calibration model. The RMSE analytical result of CH 26 with the frequency of 514 MHz; CH 42 with the frequency of 642 MHz; CH 46 with the frequency of 674 MHz; CH 54 with the frequency of 738 MHz shows that Hata's path loss model calibration is closer to the measured data than the original and the other model whereas the relative errors are closer to zero than the predicted path loss model. This makes the Hata's path loss model calibration become more accurate in the prediction and subsequently more suitable for use in planning the network design.