Locking range enhancement of divide‐by‐two injection locked frequency divider using phase shift technique

Abstract

This study presents the new locking range enhancement technique in divide-by-two injection locked frequency divider using a phase shifter circuit. The proposed divide-by-two phase shifter injection locking frequency divider (ILFD) is based on complementary metal-oxide-semiconductor (CMOS) cross-coupled oscillator with dual-resonance fourth-order LC-tank that is designed and simulated in 0.18 μm Taiwan Semiconductor Manufacturing Company (TSMC) CMOS technology. Using a phase shifter branch, an extra current with a new phase angle towards oscillator current will inject into the LC tank and moves the locking angle to a new and wider angle that leads to a wide locking range. In an analysis, the effect of the phase shifter circuit on the proposed ILFD has been explained. Simulation results show that at a supply voltage of 0.95 V, the phase shift ILFD consumes 7.32 mW power and at the incident signal power of 0 dBm the locking range is 5.25 GHz, from 4.3 to 9.55 GHz and the relative locking range is 75.81%.

Using tail current phase shift technique to improve locking range injection‐locked frequency divider

“…Recently, due to the progress of wire and wireless transceivers, the demand for broadband building blocks has been increasing. [1][2][3][4][5][6][7] One of the critical blocks which have the most crucial role in these systems is phase locked loop (PLL). As shown in Figure 1, the voltage-controlled oscillator (VCO) and frequency divider are other key components of PLL, especially the blocks placed after the oscillator VCO.…”

“…Recently, due to the progress of wire and wireless transceivers, the demand for broadband building blocks has been increasing 1–7 . One of the critical blocks which have the most crucial role in these systems is phase locked loop (PLL).…”

“…Many studies have been performed to improve the LR of the ILFDs and multipliers. Direct injection 7 proposed an LR enhancement technique using a phase shifter circuit. In Lee et al, 16 a phase tuning technique is applied to get a 25% improvement in LR, which is not enough to cover multiple applications.…”