Trirat, Akraphon

Loading...
Thumbnail Image
Preferred name
Trirat, Akraphon
Alternative Name
Trirat, A.
Main Affiliation
Email
akraphon.tr@kmitl.ac.th

Settings

Now showing 1 - 3 of 3
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Publication,
    Tunable bandpass/bandstop digital filters basedon 1st-order allpass network instead of unit delay
    (2019-07-01)
    Sutthikarn, Pemmavit
    ;
    Chivapreecha, Sorawat
    ;
    Jongsataporn, Thitaphan
    ;
    Trirat, Akraphon
    This paper presents a design and realization of tunable bandpass and bandstop digital filters based on using tunable digital lowpass and highpass filters. The frequency response of both digital lowpass and highpass filters which called prototype filters can be changed/tuned by replacing unit delay elements in filter structure with 1<sup>st</sup>-order allpass network. From the tunable digital lowpass and highpass filters, the cascade connection of them can give tunable bandpass filter, the parallel connection can give tunable bandstop filter. The conditions of using proposed tunable bandpass/bandstop filters will be analyzed and explained in this work. A high flexibility of tuning both center frequency and bandwidth can be achieved from the proposed design and realization. Simulation results also be compared with experimental results from hardware implementation on FPGA using NI-myRIO device to ensure that the obtained frequency responses are correspondence.
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Publication,
    A Simple Tunable Biquadratic Digital Bandpass Filter Design for Spectrum Sensing in Cognitive Radio
    (2020-06-01)
    Sutthikarn, Pemmavit
    ;
    Chivapreecha, Sorawat
    ;
    Trirat, Akraphon
    ;
    Jongsataporn, Thitaphan
    This article presents a design and realization of tunable digital bandpass filter based on using biquadratic filter for spectrum sensing in cognitive radio. The biquadratic bandpass digital filter structure has shown and after that the tunable approach will be derived. The bandwidth and center frequency of the proposed tunable biquadratic digital bandpass filter can be tuned by tuning parameters. In each band, energy detection by spectrum sensing method will be used by cognitive radio users (CRU) for recognize the frequency spectrum of primary user (PU). If there are not having any PU in that band, the status of band will set to spectrum hole. Eventually, CRU can utilize this channel.
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Publication,
    A tunable multiple outputs FIR filter structure realization
    (2019-01-01)
    Sutthikarn, Pemmavit
    ;
    Chivapreecha, Sorawat
    ;
    Trirat, Akraphon
    This paper proposes a design of a new finite impulse response (FIR) digital filter structure which gives 6-tunable frequency responses as 2 low-pass filters (LPF), 2 high-pass filters (HPF), 1 band-pass filter (BPF) and 1 band-stop filter (BSF) at the same time. The design procedure is initiated from 2 LPFs design. However in order to obtain a tunable filter, the unit delay is replaced by first-order single-multiplier structure for all-pass filter. Therefore, this new structure can be achieved and called tunable multiple outputs FIR filter. Finally, the amplitude responses that obtained from proposed structure can show the tunable capability using tuning parameter.