Kenpankho, Prasert

Preferred name

Kenpankho, Prasert

Alternative Name

Kenpankho, P.

Main Affiliation

School of Industrial Education and Technology

prasert.ke@kmitl.ac.th

Now showing 1 - 10 of 21

Some of the metrics are blocked by your
consent settings
Study of Ionospheric Total Electron Content over Thailand Using BeiDou Satellites
(2025-01-01)
Maichuen, Samatchaya
;
Keokhumcheng, Thanapon
;
Kenpankho, Prasert
This study aims to analyze the Total Electron Content (TEC) in the ionosphere over Thailand using BeiDou satellite signals received by BG2s receivers, providing an alternative to the traditional use of GPS satellites for investigating TEC variations. Data were collected from January to March 2025 from six monitoring stations: Bangkok, Chiang Mai, Chumphon, Nong Bua Lam Phu, Phuket, and Ubon Ratchathani, respectively, covering the entire region of Thailand. The analysis revealed that Nong Bua Lamphu recorded the highest average at 77.94 TECU, followed by Chiang Mai with 73.55 TECU. Ubon Ratchathani had an average of 65.81 TECU, while Phuket recorded 59.54 TECU, closely followed by Bangkok with 59.22 TECU. Chumphon had the lowest average maximum value at 45.00 TECU, respectively. Additionally, training sessions were conducted for 20 participants of the Meteorological Department on using BG2s receivers to measure TEC from BeiDou satellites. The pre-training assessment showed that 6 participants, accounting for 30%, achieved scores above 80%. After the training, all participants, representing 100%, surpassed the 80% threshold. The results indicate an improvement in participants' knowledge from 30% to 100%, reflecting the success of the training program and demonstrating the potential for applying the BeiDou satellite system in future ionospheric TEC studies.
Some of the metrics are blocked by your
consent settings
A Novel Short-Term Prediction Model for Regional Equatorial Plasma Bubble Irregularities in East and Southeast Asia
(2025-02-01)
Zhao, Xiukuan
;
Li, Guozhu
;
Xie, Haiyong
;
Hu, Lianhuan
;
Sun, Wenjie
Equatorial plasma bubble (EPB) irregularities can significantly impact satellite-based communication and navigation systems. Accurate prediction of EPB occurrence is essential for mitigating these impacts. Using the GNSS receiver network and ionosonde data from East and Southeast Asia during 2010–2021, and the rate of TEC change index to characterize the occurrence of EPB irregularities, we developed a novel Spatio-Temporal deep learning model for regional EPB irregularities short-term Prediction (STEP). The model integrates the convolutional neural network and long short-term memory (LSTM) network, together with attention mechanisms, to capture both spatial and temporal features of regional ionospheric irregularities. The results show that for 5-min forecast, the STEP model achieves a root mean square error (RMSE) of 0.062 TECU/min and an R<sup>2</sup> of 0.818, reducing RMSE by 19.48% compared to LSTM and 27.06% compared to gated recurrent unit model. For 60-min prediction, the STEP model can still achieve reasonable accuracy with an RMSE of 0.110 TECU/min and an R<sup>2</sup> of 0.482, showing significant improvement over traditional models. The equatorial F layer height and regional TEC fluctuations were identified as the most critical factors for predicting the generation and duration of EPB irregularities, respectively. The spatial and temporal distributions of EPB irregularities, including their latitudinal variation and delayed onset after sunset, and the occurrence across different days in East and Southeast Asia, were well predicted by the STEP. It is expected that the STEP model would provide a valuable tool for improving the resilience of GNSS against ionospheric scintillations induced by EPB irregularities.
Some of the metrics are blocked by your
consent settings
Improving the modeling of bottomside thickness parameters over midlatitudes and high latitudes
(2020-02-01)
Jamjareegulgarn, Punyawi
;
Supnithi, Pornchai
;
Kenpankho, Prasert
;
Wichaipanich, Noraset
;
Nayak, Chinmaya
This paper investigates bottomside thickness parameters at Digisonde stations over midlatitude and high latitude regions, and compares the diurnal, seasonal, and solar activity variations in 2014 and 2009. The geographic latitudes of high latitude considered in this work are located beyond ±60° and those of midlatitude are located between ±40° and ±60°. The IRI-modeled B0 with ABT-2009 option (B0_IRI) are also examined and compared with four kinds of the B0 values, i.e., the observed B0 (B0_obs) from GIRO, the computed B0 following to Jamjareegulgarn et al. (2017a) (B0_old), the calculated B0 with a correction factor regarding to Jamjareegulgarn et al. (2017b) (B0_new), and the B0 with an average correction factor (B0_new_c_av). The average correction factors are proposed additionally in this work so as to assist occasionally the experimental B0 nonexistence of Digisonde which are equal to 0.2658 and 0.2058 for midlatitudes and high latitudes, respectively. Results show that the diurnal variations of B0_new and B0_new_c_av are in a good agreement with those of B0_obs evidently compared with those of B0_IRI and B0_old at every station during the three seasons over high and middle latitudes. During the three seasons, the diurnal variations of B0_new_c_av show similar trends and are close to one another with the B0_obs and the B0_new with small deviations. The differences between the B0obs and the B0_new_c_av also show similar trends and are close to one another with those between the B0obs and the B0_new. In contrast, the B0_IRI with ABT-2009 option seems to predict the B0 values poorly during the three seasons at high latitudes and some seasons at midlatitudes. The proposed B0_new is useful for computing approximately the observed B0 and the ionogram-based total electron content (ITEC) of Digisonde, and the plasma scale height over midlatitudes and high latitudes.
Some of the metrics are blocked by your
consent settings
Ionospheric disturbances as precursor signals of the March 28, 2025, Myanmar earthquake
(2026-03-15)
Pansong, C.
;
Ruttanaburee, S.
;
Pornsopin, P.
;
Kenpankho, P.
This study examined the ionospheric response associated with the Mw 7.7 Myanmar earthquake on March 28, 2025, using GPS-derived Total Electron Content (TEC) data from seven GNSS stations across Thailand. TEC variations were analyzed alongside Dst and Kp indices, as well as ionosonde-derived parameters, namely the critical frequency of the F2 layer (foF2), the peak height of the F2 layer (hmF2), the disturbances in NmF2, and the slab thickness (τ), which were obtained from three IGS-supported stations. We detected abnormal variations in TEC approximately 15 days before the earthquake (13–27 March 2025), characterized by alternating positive and negative deviations. The TEC exhibited alternating positive and negative deviations throughout the analysis period, reflecting ionospheric variability prior to the earthquake. During the early period (13–18 March), the deviations remained within approximately ±6 TECU. However, from 19 to 21 and 23–24 March, moderate fluctuations were observed, particularly at mid- and low-latitude stations (UTHG, THBK, THCP, and THPK), where ΔTEC ranged from ±6 to 10 TECU. The TEC decrease occurred on 25 March under weak geomagnetic conditions (Dst > −30 nT) at the northern stations MAEH (−18.40 TECU), THCM (−15.65 TECU), and NANN (−15.73 TECU), marking the most pronounced negative anomaly observed during the study period. Subsequently, on 26–27 March, TEC values recovered to positive anomalies of +4 to +10 TECU, indicating a return to normal ionospheric conditions. To objectively identify pre-seismic ionospheric anomalies, a Median Absolute Deviation (MAD) approach was applied using a ±1.34MAD threshold. This statistical technique effectively detects subtle deviations while minimizing transient noise. The results reveal coherent TEC depletions across multiple stations on 25 March, suggesting the presence of localized ionospheric disturbances potentially related to seismo-ionospheric processes rather than geomagnetic effects. Furthermore, concurrent anomalous increases in foF2 and hmF2, along with a reduction in slab thickness near the epicentral region, indicate vertical uplift of the F2 layer, consistent with possible Lithosphere–Atmosphere–Ionosphere Coupling (LAIC) mechanisms.
Some of the metrics are blocked by your
consent settings
Galileo-E6 Bandwidth Frequency Filter Design for Galileo Receiver
(2021-09-01)
Chinnapark, Surachet
;
Onanong, Narumol
;
Pattameak, Julongkorn
;
Mekpradab, Teerachet
;
Kenpankho, Prasert
This research discusses about the combination of the LPF and HPF to perform band reject filter. Therefore, there are two combination also in designing band reject filter. The aim of this combination to get know is there have an influence on the performance of band reject filter was designed by using the frequency of the GalileoE6 with bandwidth 40 MHz. This filter is used a Butterworth filter which is presented in this study. These filter circuit is composed 4rd order. In addition to, the combination between LPF and HPF forming to a band reject filter is designed. As a result, the filter design on the frequency of Galileo-E6 is successfully used in band reject filter.
Some of the metrics are blocked by your
consent settings
GNSS Receiver Bias Model for Near Real Time TEC Monitoring at Low Latitude, Thailand
(2026-01-01)
Kenpankho, Prasert
;
Maichuen, Samatchaya
;
Phothila, Prarinya
;
Zhang, Jianfeng
;
Keokhumcheng, Thanapon
This research proposes and investigates GNSS receiver bias modeling for near real time total electron content (TEC) monitoring across 16 multi-frequency GNSS stations in low latitude, Thailand, from 2022-2024. By applying a refined methodology based on Kenpankho et al. (2021) and integrating IONOLAB-BIAS for single station bias estimation, the research corrects for satellite and receiver inter-frequency biases to enhance TEC accuracy. Results show a consistent upward trend in TEC values, reflecting increased latitudes, seasonal ionospheric activity, and geomagnetic storms. Comparative analysis with the IRI 2020 model using correlation coefficients and RMSE reveals spatial and temporal variation, with near equatorial latitude stations showing strong alignment than upper low latitude stations. The results highlight the importance of localized GNSS-based TEC models for improving satellite positioning accuracy in equatorial regions and highlight the limitations of global models under dynamic ionospheric conditions.
Some of the metrics are blocked by your
consent settings
The Study of GPS Total Water Vapor Content over Ubon Ratchathani
(2025-01-01)
Wongsak, Pattawut
;
Kraisi, Prasert
;
Kenpankho, Prasert
The research paper focused on learning and investigating water vapor in the atmosphere over Ubon Ratchathani, Thailand. Water vapor can be measured by using total water vapor content (TWVC) which is calculated by Global Positioning Satellites known as GPS which are over Thailand and receives signals passively which can be extracted by BG2s receiver. In this research study, Ubon Ratchathani is selected and installed BG2s receiver according to the weather and environment conditions where are among mountains, rivers, and lands with large population and agriculture occupation. TWVC can be obtained by GPS signals which are in Receiver Independent Exchange (RINEX) format. For calculating TWVC, the used altitude in troposphere over Ubon Ratchathani is five kilometers. The period of this research study was from August-October 2024 over Ubon Ratchathani. GPS datasets were analyzed and processed to Total Electron Content (TEC) estimation, converted it as ionospheric delay and estimated it as the zenith tropospheric delay (ZTD). Then, personnel at the Thai Meteorological Department (TMD) were trained and investigated the TWVC values from GPS with the TWVC values from measurement by TMD. As the results, we found that the maximum TWVC was recorded at Ubon Ratchathani in September 2024, with an average of 15.30 mm and the minimum TWVC was in October 2024, with average of 7.39 mm. The pretest and posttest were different values, which pretest score is smaller than the posttest score at 13.39. In addition, the investigation TWVC values from GPS underestimated the TWVC values from measurement by TMD at 1.5 times.
Some of the metrics are blocked by your
consent settings
Galileo-E5a Bandwidth Frequency Filter Design for Galileo-E5a Receiver
(2022-09-01)
Mekpradab, Teerachet
;
Onanong, Narumol
;
Chinnapark, Surachet
;
Pattameak, Julongkorn
;
Kenpankho, Prasert
This study focused on the design of the band-reject filter on the frequency of the Galileo satellite by providing bandwidth at the cut-off frequency equal to the bandwidth of the Galileo-E5a. The selecting of response characteristic is Butterworth's maximally flat, amplitude-frequency response of the band-reject filter. This poster shows the combination of the LPF and HPF to perform a band-reject filter. Therefore, there are two combinations also in designing for the band-reject filter. This combination aims to influence the performance of the band-reject filter. Band rejects filter design using the frequency of the Galileo-E5a with bandwidth is 25 MHz.using a Butterworth filter which is presented in this poster. The circuit is composed 3rd.order.Moreover, the combination between LPF and HPF is designed to act as a band-reject filter. As a result, we can filter the frequency of Galileo-E5a by using the band-reject filter.
Some of the metrics are blocked by your
consent settings
Global Navigation Satellite System (GNSS) Low-Cost Robotics Platform for Competition Game
(2025-01-01)
Sumniang, Patiphan
;
Putthong, Burin
;
Namniwong, Thapanan
;
Kenpankho, Prasert
In this research, the Global Navigation Satellite System (GNSS) low-cost robotics platform for competition game was designed, including the development of competition rules and field. The competition rules are specifically tailored to GNSS low-cost robot, highlighting the essential components required to build robots based on GNSS low-cost robotic platform. This research aims to promote learning and skill development in robots and GNSS, with a focus on affordable resources to ensure accessibility for students and independent developers. In research methodology, a total of 58 teams with 116 participants took part in the GNSS low-cost robotics platform competition game, including 47 high school level teams (94 participants), 6 vocational level teams (12 participants), and five undergraduate level teams (1 0 participants). As the results, the competition game was successfully developed by the GNSS low-cost robotic platform, with over 70% of participants demonstrating a solid understanding of GNSS navigation, robot, and game design. Participants rated innovation-focused activities highly (4.55), highlighting the competition game role in inspiring creativity in GNSS and low-cost robot. In term of rule for competition game, participants gave the rates on fairness (4.23) and consistency (4.28) which were well received, although rule clarity received the lowest score (3.84), suggesting the need for clearer guidelines. In addition, the pre- and posttest assessments on participants' knowledge, understanding, and inspiration in GNSS navigation, robot, and game design, further confirmed the effectiveness of GNSS low-cost robotics platform competition game by giving the improved mean score from 23.06 to 27.01.
Some of the metrics are blocked by your
consent settings
Complex Ionospheric Irregularity Echoes Observed by Low Latitude Long Range Ionospheric Radar
(2026-01-01)
Li, Yuxiao
;
Hu, Lianhuan
;
Li, Guozhu
;
Ning, Baiqi
;
Dai, Guofeng
Using the Low lAtitude long Range Ionospheric raDar (LARID) at Dongfang (19.2°N, 108.8°E), Hainan Island, China, we report a unique case of complex ionospheric irregularities observed on 9 June 2024. The most interesting aspect is the first-time long-range (∼2,000 km) detection of daytime ionospheric irregularities and post-sunset band-like irregularity structures by HF radar at low latitudes. By incorporating VHF radar and global navigation satellite system (GNSS) rate of total electron content index (ROTI) observations, the radio wave propagation modes of the ionospheric irregularity events observed by LARID and evolution of these ionospheric irregularities were analyzed. The daytime ionospheric irregularity echoes observed by LARID over the Indian Ocean exhibited westward drift, evident in both echo patterns and Doppler velocities. These ionospheric echoes were likely backscattered from E region field aligned irregularities by the “downleg” of the 1-hop HF ray path. The post-sunset irregularity echoes observed by LARID over Indian Ocean manifested as a band-like structure. This structure was closely attached to the bottom of ground/sea scatter echoes and showed the same range variation as the ground/sea scatters. GNSS ROTI observation revealed that irregularities primarily appeared south of the magnetic equator and drifted eastward across the eastern longitudes in later hours. Analysis indicates that the displacement of small-scale irregularities within the equatorial plasma bubble event along the magnetic field likely contributed to the band-like irregularity structure observed by LARID and the asymmetric irregularity distribution observed by GNSS.

Kenpankho, Prasert

Filters

Settings

Sort By

Results per page