Compact design of four-phase fractional-order oscillator with independent phase and frequency control

On the performance of electronically tunable fractional-order oscillator using grounded resonator concept

“…The direct form of the gain A expression in (8) clearly indicates the required energy (gain) given by a specific selected oscillation frequency and orders (and values) of the used CPEs. The key parameter for the condition adjustment has been similarly expressed for example in [13], [15], [19]- [21], [23]. It is clear, that the condition fulfilment depends on the oscillation frequency and orders of CPEs (α, β).…”

“…There is only one AE (voltage differential inverted and buffered amplifier, abbreviated as VDBI) having features similar to [11] and [12]. In [15], three DDCCs as AEs including all grounded passive elements were also selected for a multiphase design. It indicates that a complex active device (internal principle) can significantly help with the implementation of grounded passive elements.…”

“…On the other hand, individual transistors as the simplest active devices can be also used in the design of fractional-order oscillators [16]. In [15], the active device, used in topology allowing grounded CPEs, is similarly complex as device in our work. Additional value of our proposal, in comparison to [15] (see Table 1 for further details), is that it provides benefits regarding easy electronic tunability, phase shift maintained constant, etc.…”

“…In [15], the active device, used in topology allowing grounded CPEs, is similarly complex as device in our work. Additional value of our proposal, in comparison to [15] (see Table 1 for further details), is that it provides benefits regarding easy electronic tunability, phase shift maintained constant, etc. in comparison to the topologically simplest solutions (for example [16]).…”

Design and realisation of a fractional‐order sinusoidal oscillator

“…The effects of different approximation techniques on the performance of the fractional oscillators are studied in [26, 28]. Multi‐phase oscillators that use three or more fractional‐order capacitors have been proposed in [8, 14, 15, 19, 21, 25]. For a multi‐phase signal generation, fractional‐order all‐pass filter blocks have been employed in [8], on the other hand, fractional‐order lowpass sections have been utilized in [15, 21].…”