Jamjareegulgarn, Punyawi

Preferred name

Alternative Name

Jamjareegulgarn, P.

Main Affiliation

KMITL Prince of Chumphon Campus

punyawi.ja@kmitl.ac.th

Now showing 1 - 10 of 14

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Detection of data symbol in a massive MIMO systems for 5G wireless communication
(2017-10-19)
Duangsuwan, Sarun
;
Jamjareegulgarn, Punyawi
The massive MIMO technique has played the most important role in 5G wireless communication. It is anticipated that the new techniques employed in massive MIMO will not only improve peak service data rates significantly, but also enhance capacity, coverage, low-latency, efficiency flexibility, compatibility and convergence, thus meeting the focusing demands imposed by optimal detection. This paper presents the optimal detection of data symbol in massive MIMO for 5G wireless communication. Based on the frequency non-selective fading MIMO channel, we consider three difference detectors for recovering the transmitted data symbols and evaluate their performance for Rayleigh fading and additive white Gaussian noise (AWGN). At the results, we show that the probability of error rate (PER) performance of the detectors are significantly discussed.
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Evaluating cooperative diversity-based WBAN by using STBC with pre-coding and relay selection
(2014-01-01)
Jamjareegulgarn, Punyawi
The main objective of this paper is to evaluate the network performance of a cooperative diversity-based wireless body area network (WBAN) by using (2,2) Alamouti's space-time block code (STBC) with pre-coding scheme (STBC-PC) and a relay selection procedure (RSP). The considered WBAN model is served for healthcare service in order to mitigate the undesired effects of WBAN due to high path loss and fading as well as to keep a low transmit power while meeting to the desired WBAN quality of services. In this paper, the pre-coding scheme is taken to be employed in conjunction with the STBC, since a single antenna of each wireless sensor node in healthcare service can be exploited possibly as well as the high gain can still be achieved without loss of transmission rate. A channel model CM3 B is considered for computing the actual path loss of each WBAN link and the network performance is evaluated in terms of bit error rate (BER). The simulation results confirm that at each BER value, SNRs of STBC-PC without direct link (line-of-sight or LOS) scheme are the lowest which is compared with direct link, receive diversity and MRC, and (2,2) Alamouti's STBC. BER values of DQPSK-based STBC-PC are higher than those of DBPSK-based STBC-PC. Moreover, although any WBAN sensor nodes are chosen as a relay or any type of modulations are employed in STBC-PC with LOS, all of BER values have surprisingly the same trend. © 2014 IEEE.
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Analysis of Bottomside Thickness Parameter-Based TEC at Equatorial and Low Latitude Stations for Global Navigation Satellite Systems
(2018-07-02)
Jamjareegulgarn, Punyawi
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Duangsuwan, Sarun
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Tangtrakunphaisan, Udomsit
This paper studies the total electron content (TEC) at equatorial and low latitude stations which is computed using an equation of bottomside thickness parameter with correction factor (B2botP-new) during the solar maximum of 24th solar cycle. The computed TEC is used to compute the ionospheric time delay subsequent-tially. The ionospheric stations in this work include Ramey, Ascension Island, and Jicamarca. The results show that the diurnal and seasonal variations of B2botP-new have the same trends as that of B0-obs as well as the B2botP-new values are close to the BO-obs values clearly for all three stations. The electron density diffuses from the equator toward the EIA region (15°N and 15°S) during the period of 14-23 LT. The proposed TEC (TEC-P) are computed using the B2botP-new, and then the ionospheric delay is also computed using the TEC-P. The computed TEC-P and Id-P are close to the TEC-obs and Id-obs, but they should be further studied for a solar cycle (11 years).
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Performance evaluation for cooperative diversity-based wireless body area network
(2013-01-01)
Jamjareegulgarn, Punyawi
This paper proposes cooperative diversity-based wireless body area network (WBAN) for healthcare service in order to mitigate the undesired effects of WBAN due to high path loss and fading as well as to keep a low transmit power while meeting to the desired WBAN quality of services, i.e., low outage probability and low bit error rate. In this paper, we consider all of the sensors which are placed on the human body, so CM3 B channel model is taken into account for computing the path loss of each WBAN link. Three well-known schemes for proactive relay selection have been addressed and applied in WBAN so as to compare the performance with the direct communication. The performance is evaluated in terms of outage probability (P<inf>out</inf>) and bit error rate (BER). The simulation results confirm that P<inf>out</inf> of cooperative diversity-based WBAN can be reduced higher 99.68% than that of direct communication at SNR of 0 dB and can be achieved below 4.5*10<sup>-4</sup> at the low SNR of 0 - 6 dB. Moreover, BER of cooperative diversity-based WBAN can also be significantly decreased higher 99.89% than that of direct communication at all SNRs of 0 - 10 dB. © 2013 IEEE.
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A new expression for computing topside scale height for satellite-based communications
(2017-10-19)
Jamjareegulgarn, Punyawi
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Supnithi, Pornchai
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Hozumi, Kornyanat
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Tsugawa, Takuya
It is well-known that the NeQuick 2 model provides analytical expressions showing a relationship between topside and bottomside ionospheres. Its bottomside thickness parameter (B2bot) is a key parameter for studying topside electron density profile (EDP) and topside parameters, and its topside scale height (Hsc) is also used to identify the topside electron density profile. The B2bot computed using ionogram-derived ionospheric parameters can be used to calculate the Hsc. Unfortunately, the Hsc computed by the original B2bot expression (Hsc old) are significantly higher than the scale heights obtained from digisondes (Hm) and the diurnal variations of the Hsc old are quite different from those of the Hm. Hence, a new expression of B2bot for computing the Hsc is suggested in this work relying on the available expressions of the NeQuick 2 model. Our results show that (1) the Hsc computed by the new expression of B2bot (Hsc new) are comparable to the Hm and the diurnal variations in Hsc new are the same trends as those in Hm; (2) all of the scale heights show diurnal variations with higher values during daytime than during nighttime and the secondary peaks can be found different local times relying on the locations; and (3) the peaks of scale height cause higher absolute differences between Hsc new and Hm (D SH).
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A Study of Air Pollution Smart Sensors LPWAN via NB-IoT for Thailand Smart Cities 4.0
(2018-08-06)
Duangsuwan, Sarun
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Takarn, Aekarong
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Nujankaew, Rachan
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Jamjareegulgarn, Punyawi
The problem of air pollutant has to improve urgently, in particular, approach to smart city in 2024 of Thailand 4.0. This paper presents a development of smart sensors of air pollution to monitor the air quality in smart city. We propose the smart sensors that consist of the particulate matter (PM<inf>10</inf>) or dust sensor, carbon monoxide (CO), carbon dioxide (CO<inf>2</inf>), noise level (dB), and ozone (O<inf>3</inf>) respectively. These sensors are solution of a low power wide area network (LPWAN). In the experiment, the measurement has been investigated in Bangkok metropolitan, and the results show air quality index (AQI) via Norrowband Internet of Things (NB-IoT). The proposed of this paper can help the people know the real-time air quality via IoT as a service.
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A comparative study of ionospheric profile parameters B0 and B1 over Chumphon with IRI-2012
(2015-08-17)
Jamjareegulgarn, Punyawi
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Supnithi, Pornchai
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Wichaipanich, Noraset
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Ishii, Mamoru
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Maruyama, Takashi
Average diurnal variations of ionospheric profile parameters B0 and B1 in 2009 are studied over Chumphon province, Thailand, and compared those variations with IRI-2012 model. The thickness parameter (B0) and the shape parameter (B1) are two main parameters to compute and depict the F2-layer electron density profile. IRI-2012, the latest version of IRI model, offers three options to provide B0 and B1, i.e., Bil-2000, Gul-1987, ABT-2009. Those options have never been taken for studying and comparing with the ionospheric observation data from a FM/CW ionosonde, Chumphon. Moreover, the observed B0 and B1 from Thailand have never been analyzed nor used while establishing the new table of (B0, B1) values of the IRI model. Hence, B0 and B1 observation is necessary as a part of the global validation study of the IRI-2012 model. Our studies show that: (1) In general, the average diurnal variations of B0 for the observation and the IRI-2012 model show the same trends, except B0 of Gul-1987 during 20:00 - 02:00 LT. The observed B0 averages are equal to 166.13 km and 99.18 km in the daytime and nighttime, respectively. (2) The average diurnal variations of B1 for the observation and the IRI-2012 model show the same trends, except B1 of ABT-2009. Average diurnal variations of the observed B1 look like a sine wave where the peak and lowest values can be found around the midnight and the noontime, respectively. For the IRI-2012 model, B1 of Gul-1987 is the same value as B1 of Bil-2000. The observed B1 averages are equal to 1.98 and 2.51 in the daytime and nighttime, respectively. Our observed B0 and B1 results are similar to other studies in equatorial latitude and low latitude stations. Our comparative studies provide some details for improving B0 and B1 parameters of CCIR-based IRI model in the equatorial latitude region.
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A new expression for computing the bottomside thickness parameter and comparisons with the NeQuick and IRI-2012 models during declining phase of solar cycle 23 at equatorial latitude station, Chumphon, Thailand
(2017-07-15)
Jamjareegulgarn, Punyawi
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Supnithi, Pornchai
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Watthanasangmechai, Kornyanat
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Yokoyama, Tatsuhiro
;
Tsugawa, Takuya
This paper proposes a new expression for computing the bottomside thickness parameter at equatorial latitude station, Chumphon (10.72°N, 99.37°E), Thailand. Its diurnal variations from 2004 to 2006 at this location are then studied. The proposed expression is derived based on two experimental data sources: FMCW ionosonde and dual-frequency GPS system, and some expressions of the NeQuick 2 model. Hence, after both the bottomside thickness parameter computed by the proposed equation, B2bot_Pro, and the bottomside shape parameter (namely, B1_Pro in this work) are computed, the bottomside electron density and the height where the bottomside electron density drops down to be 24% of the NmF2 (namely, h0.24) can be computed and shown in this work using the analytical functions of the IRI model. Moreover, the diurnal variations of the B2bot_Pro are compared with those computed from the NeQuick model, B2bot_NeQ, and the predicted B0 of the IRI-2012 model with ABT-2009 and Bil-2000 options (namely, “B0_ABT” and “B0_Bil”, respectively). The averaged, minimum, and maximum values of percentage deviations among these bottomside thickness parameters are also computed and shown in this work. Our results show that the diurnal variations of B2bot_Pro at Chumphon station have the following patterns: they start to increase during nighttime to the first peaks during pre-sunrise hours, and then decrease abruptly to their minimum values during sunrise hours. Afterward, they increase again to reach the second peaks around local noontime and fall gradually to their starting times during 20–04 LT. The diurnal variations of B2bot_Pro follow generally the same trends as those of the B2bot_NeQ and the B0_ABT, except pre-sunrise hours. The pre-sunrise peaks and sunrise collapses in both the B2bot_NeQ and the B0_ABT can be found occasionally. On the other hand, the diurnal variations in B2bot_Pro differ from those in B0_Bil due to the flattened variation in B0_Bil and the pre-sunrise peaks as well as sunrise collapses in B0_Bil disappear. The pre-sunrise peaks of the B2bot_Pro at the Chumphon station are higher than those of the B2bot_NeQ, the B0_ABT, and the observed B0 at other regions. Furthermore, the percentage deviations between the B2bot_Pro and the B0_ABT (PD_B2B0ABT) are mostly lower than 30% for all seasons of the studied years, opposite to the other percentage deviations studied in this work. The proposed B2bot_Pro parameters in this work follow a similar trend to the B2bot_NeQ and the B0_ABT, but it is not conclusive that the proposed values are equivalent to them.
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Variations of ionospheric slab thickness over the magnetic equator of Southeast Asia
(2016-09-06)
Jamjareegulgarn, P.
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Supnithi, P.
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Watthanasangmechai, K.
;
Yokoyama, T.
;
Tsugawa, T.
In this paper, the diurnal and seasonal variations of the ionospheric slab thickness in an ionosonde chain over magnetic equator of Southeast Asia are studied. Three ionosonde stations of SEALION project located along the magnetic meridian of 100°E are selected to investigate, including two stations in Thailand, namely Chumphon and Chiang Mai, and one station in Indonesia, namely Kototabang. The monthly hourly medians of the foF2 from three ionosonde stations in 2010 are used to compute the observed NmF2. Refer to the TEC data; it can be obtained directly from GPS receiver at Chumphon station since the TEC data in 2010 were observed completely. In contrast, the TEC data at Chiang Mai station lost extremely and those at Kototabang station were unavailable. Hence, the TEC data used for these two stations are obtained from the International GNSS service (IGS). Our results show that 1) for all seasons, the NmF2 values during daytime have the successive decreasing values from Chiang Mai, Kototabang, and Chumphon. While the NmF2 values at three stations are almost identical during nighttime; 2) for all seasons at these three stations, the TEC values in the daytime are larger than those in the nighttime and their maximum values in the equinox and winter are higher than those in the summer; 3) the slab thickness values in all seasons during nighttime are generally larger than those during daytime for all three stations. Meanwhile, during daytime for all seasons, the slab thickness at Chumphon station is the highest among these three stations due to the fountain effect over magnetic equator.
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A correction factor of bottomside thickness parameter for computing TEC in global navigation satellite systems
(2017-10-19)
Jamjareegulgarn, Punyawi
;
Supnithi, Pornchai
;
Hozumi, Kornyanat
;
Tsugawa, Takuya
This paper proposes two new equations for computing the bottomside thickness parameter of the NeQuick 2 model with a correction factor (B2bot Pro2) and the simulated TEC values (TEC Pro). The main contributions of this work are twofold, i.e., 1) the proposed B2bot Pro2 equation can be used to compute the bottomside thickness whose trends and values are close to ones of the observed B0 (B0 obs) obtains from DPS-4 (Digisonde) and 2) the computed B2bot Pro2 are used to compute the TEC values without additional TEC observation by any devices and TEC computation. In this case, it is useful for some locations where there exist only ground-based ionosonde without TEC observation or TEC measurement doesn't work in some situations. The results show that the B2bot Pro2 have the same trends as the B0 obs. They are closer to the B0 obs, except at 13LT in June solstice and September equinox. The averages of absolute differences between B2bot Pro2 and B0 obs (avAD Pro2) are generally lower than about 8 km. They show that the B2bot Pro2 are close to the B0 obs with the improved percentages of higher than 80%. The TEC computed using the B2bot Pro2 equation (TEC Pro) in the nighttime are generally close to the observed TEC (TEC obs) compared with those in the daytime.

Jamjareegulgarn, Punyawi

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