Sub-mW $LC$ Dual-Input Injection-Locked Oscillator for Autonomous WBSNs

This paper presents a sub-mW, current-reused first-harmonic LC injection-locked oscillator (ILO) using in-phase dual-input injection technique. It can be used as a power oscillator in the injection-locked transmitter of wireless biomedical sensor nodes (WBSNs) integrated into a wireless body area network. A prototype chip, implemented in a standard 0.13-μm CMOS process occupying 200 × 380 μm, operates in the medical implantable communications service (MICS) band for medical implants. Measurement results show that the proposed ILO features a wide locking range of 800 MHz (150-950 MHz) at an input power of 0 dBm. More importantly, it has a high input sensitivity of -30 dBm to lock the 3-MHz bandwidth of the MICS band, while consuming only 660 μW at 1-V supply. This ultralow power consumption enables autonomous WBSNs.