Pakasiri, Chatrpol

Preferred name

Pakasiri, Chatrpol

Alternative Name

Pakasiri, Charpol

Main Affiliation

Integrated Innovative Technology

chatrpol.pa@kmitl.ac.th

Now showing 1 - 10 of 11

Some of the metrics are blocked by your
consent settings
Compact Wilkinson Power Divider Using Composite Right/Left-Handed Transmission Line on CMOS Process
(2020-03-01)
Nithiporndecha, Kittipong
;
Wang, Sen
;
Pakasiri, Chatrpol
This paper shows the design and analysis of CMOS Wilkinson power divider using composite right/left-handed transmission lines. The effects of lossy components in the circuit are also analyzed. The circuit is then implemented on a 0.18-μm CMOS process. The return losses are less than -16 dB, the isolation is better than -26 dB, and the insertion losses are better than -5.15 dB at the frequencies of interest. Its chip size is 0.5 mm2 (9.9e-5λ<inf>o</inf>2) including testing pads.
Some of the metrics are blocked by your
consent settings
Impedance Extraction using Impedance Perturbation Method of Electrically Small HF Loop Antenna with Undercover Ferrite Sheet
(2018-12-24)
Mangmisirisap, Kanthiphat
;
Bandudej, Kamorn
;
Pakasiri, Chatrpol
Electrically small high frequency (HF) loop antenna with undercover ferrite sheet yields high radiation resistance for multi-Turn structure. Antenna impedance without radiation differs greatly from that with the radiation effect. Impedance perturbation method is used for extracting antenna impedance with radiation effect at a desired frequency. Matching networks are designed based on the extracted antenna impedance. The measurement results show that the antenna with the designed matching network provides higher return loss.
Some of the metrics are blocked by your
consent settings
Improvement of transmission line circuit on lossy substrate with application on phase shifter design
(2019-03-01)
Pakasiri, Chatrpol
;
Kongchayasukwat, Thitipun
Lumped transmission line circuit design on lossy substrate is studied in this paper. Conventional single section lumped transmission line cannot perform well on lossy substrate as its electrical length gets longer. Multi-section transmission lines can be used to improve transmission line properties in this case. Phase shifter circuits are designed with a large electrical length transmission line. By using a multi-section transmission line, the resulting transmission line properties are better than those of single section transmission line.
Some of the metrics are blocked by your
consent settings
Wireless power transfer system design using electrically small HF loop antennas
(2019-03-01)
Mangmisirisap, Kanthiphat
;
Bandudej, Kamorn
;
Pakasiri, Chatrpol
Wireless power transfer system design with inductive power transfer is proposed in this paper. The system input and output impedances are extracted by using impedance perturbation method. Using matched capacitors, the measured system reflection coefficient magnitude at 13.56 MHz is as low as 0.04 and the transmission coefficient magnitude is at 0.95.
Some of the metrics are blocked by your
consent settings
Study performance of near-field HF antenna using undercover ferrite sheet
(2017-10-19)
Kankhunthod, Kittipon
;
Pakasiri, Chatrpol
A planar loop antennas with and without undercover ferrite are studied in this paper. The field simulated results show that the antenna with undercover ferrite provides more magnetic flux density at the same distance away from it. Using a receiving loop antenna in the simulation, the power gain of both transmitting antennas is compared. By using proper matching networks, the planar loop antenna with undercover ferrite provides a better power gain than that of the planar loop antenna.
Some of the metrics are blocked by your
consent settings
2.4 GHz Rat-Race Coupler with Complex Termination on IPD Process
(2018-12-24)
Pakasiri, Chatrpol
;
Wang, Sen
This paper proposed a rat-race circuit implement on IPD (Integrated Passive Device) process. The termination loads of the circuit have a complex impedance value. Design equations for single frequency operation of distributed structure are provided. Lumped components representation of distributed structure is illustrated in the design example. The measured results yield-5.6 dB reflection coefficient at the input port and-14 dB transmission coefficient at the isolation port. The transmission coefficients at the output ports are better than-7 dB while the phase difference is less than 2 degrees.
Some of the metrics are blocked by your
consent settings
Simple Class F Power Amplifier Design with Fundamental Frequency Tuning
(2020-03-01)
Manasammakij, Prateep
;
Pongthavornkamol, Tiwat
;
Pakasiri, Chatrpol
Simple class F with medium output power at 433 MHz is designed and simulated in this paper. The design process uses fundamental frequency tuning in find the matching network. At fundamental frequency, the reactance part of the networks needs to be conjugate values of that of the output impedance of the transistor circuit while the resistance part of the network is found by running simulation sweep. The second and third harmonics are also considered in the matching network design. Using the designed matching networks, the amplifiers yield almost optimum efficiency values for input power of 13 and 18 dBm. The proposed technique can save computational costs comparing to load pull technique. In future work it can lead to implementation of a class F power amplifier without using load pull.
Some of the metrics are blocked by your
consent settings
A Compact 1-5.2 GHz Wideband Low Noise Amplifier
(2019-11-01)
Pakasiri, Chatrpol
;
Yang, Nien Sheng
;
Wang, Sen
A wideband, low noise figure, cascade amplifier is presented in this paper. The proposed low noise amplifier is designed and fabricated in UMC 0.18 μm CMOS technology. In addition, this amplifier uses a resistor-feedback architecture. And this resistor-feedback amplifier contains the PMOS, NMOS and resistors form the amplifier architecture. The measurement results show that for the proposed low noise amplifier, the gain is above 10 dB at the bandwidth of 0.38-5.3 GHz, a maximum P1dB of -15 dB, a minimum NF of 4 dB and operating bands of return loss is greater than 12 dB.
Some of the metrics are blocked by your
consent settings
Improvement of HF RFID reader performance under metallic environment using ferrite sheet
(2017-12-19)
Kankhunthod, Kittipon
;
Lekawat, Lertsak
;
Pakasiri, Charpol
Conventional loop antennas for RFID reader usually perform worse with metallic environment. To improve reading range under this condition, a ferrite sheet is incorporated in the conventional loop antenna. The proposed antenna yields similar reading range with or without metallic environment.
Some of the metrics are blocked by your
consent settings
A 433 MHz compact complex impedance-Transforming balun
(2017-12-19)
Pakasiri, Charpol
;
Nithiporndecha, Kittipong
A 433 MHz compact size balun that can transform a complex source impedance value to a complex load impedance value is demonstrated. The balun design is based on a coupled-line coupler balun. The simulation shows a good performance at 433 MHz operating frequency.

Pakasiri, Chatrpol

Filters

Settings

Sort By

Results per page