Chivapreecha, Sorawat
Loading...
Preferred name
Chivapreecha, Sorawat
Alternative Name
Chivapreecha, S.
Chivapreecha, Sorwat
Main Affiliation
Email
sorawat.ch@kmitl.ac.th
2 results
Now showing 1 - 2 of 2
- Some of the metrics are blocked by yourconsent settings
Item type:Publication, Continuously Tunable Frequency and Phase Biquad Oscillator(2026-05-01); Suwannawach, PiyapanThis paper presents an improvement to the performance of a biquad oscillator, which is a recursive oscillator known for its excellent long-term stability. However, a significant limitation is that the oscillation frequency cannot be changed while the system is operating. Directly changing the frequency during operation causes the amplitude of the generated signal to vary significantly, either increasing or decreasing. A zero-input response analysis is used to understand the cause of this problem and to develop a solution that allows the amplitude of the generated signal to remain constant even when the oscillation frequency is changed during operation. In addition, this paper presents a method for controlling the phase of the generated signal by using a 1st-order IIR phase shifter structure. The proposed structure is specifically designed to allow the phase of the signal at the oscillation frequency to be adjusted continuously and independently of the frequency parameter. This integrated oscillator enables real-time, independent control of both signal frequency and phase without amplitude drift, making it suitable for applications requiring precise and dynamic signal synthesis. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Tunable 1st Order IIR Phase Shifter Design and Implementation(2024-01-01); Jongsataporn, ThitaphanThis paper presents a new phase shifter which is a first-order infinite impulse response (IIR) filter that can shift phase both in phase-lead (0° to+180°) and phase-lag (-180° to 0°) fashion. Moreover, continuous phase tuning is also proposed in our phase shifter. The z-transform pair of phase-shifted cosine signal is utilized as the origin, then factorization of such term can give transfer function of first-order IIR phase shifter. The filter structure realization of the tunable phase shifter will be shown and applied with a digital cosine oscillator. Both simulation and hardware experiments can show phase-shifted signals in real-time controlled by phase-tuning parameters compared with a cosine reference signal as a demonstration. The allpass phase shifter will be used as a benchmark, and trade-off analysis using the proposed phase shifter will also be discussed.