A 470-$\mu{\hbox {W}}$ 5-GHz Digitally Controlled Injection-Locked Multi-Modulus Frequency Divider With an In-Phase Dual-Input Injection Scheme

A ring-type ILFD with locking range of 91% for divide-by-4 and 40% for divide-by-8 with quadrature outputs

“…As can be seen from TABLE I, the FOM T of the proposed ILFD is extraordinary higher than the others, except for [11]. One of the reasons of that is the benefit of our ILFD to work with low input power especially in the case of divide-by-8.…”

“…An ILFD can be defined as an oscillator that is synchronized with an incident signal. There are two types of ILFDs: LCtype ILFDs [3][4][5] and ring-type ILFDs [6][7][8][9][10][11]. The problem with LC ILFDs is their narrowband characteristics due to the high quality factor (Q) of the LC tank.…”

6.2 GHz 0.5 mW two‐dimensional oscillator array‐based injection‐locked frequency divider in 0.18 μm CMOS

“…1 shows a simplified N ‐stage ring oscillator‐based ILFD. Since the operating frequency of the ring oscillator is inversely proportional to the total delay of the loop, it is therefore possible to design an ILFD that is able to work at different operating frequencies by adjusting the delay in the oscillator core [3, 4]. In these designs, the delay in the oscillator core is obtained by switching of the delay cell or the proper sizing of transistors.…”

“…Introduction: The high-speed frequency divider is a key block in frequency synthesisers for wireless communications [1][2][3][4]. The dualmodulus or multi-modulus prescaler is the most challenging block among all kinds of frequency divider designs for its highest operating frequency in the system while variable division ratios are desired.…”

“…The injection-locked frequency divider (ILFD), owing to its ultra-high operating frequency and low power consumption, has been regarded as an ideal candidate in high-speed frequency dividers. Several ILFDs with variable division ratios have been demonstrated in the recent literature [1][2][3][4]. However, the delay of the oscillator core in these dividers should be properly adjusted to obtain different division ratios, where proper sizing of devices or delay lines is needed.…”