Power-Efficient Spin-Torque Nano-Oscillator-Based Wireless Communication With CMOS High-Gain Low-Noise Transmitter and Receiver

Abstract

A low-power spin-torque nano-oscillator (STNO)-based wireless communication is demonstrated with a 180 nm CMOS transmitter and receiver. The on-off keying (OOK) modulation is employed to overcome the inherent drawbacks of the STNO, such as low output power and spectral purity, despite its advantages of a wide frequency tuning range and nano-scale dimensions. As the magnetic-tunnel-junction (MJT) STNO with an MgO barrier has a maximum oscillation power as small as -75 dBm at 3.39 GHz, a 68 dB high-gain amplification throughout the transmitter and receiver is needed for a 1 m wireless communication. A 36 dB high-gain amplifier with a 3.9 dB low noise figure is implemented for the OOK transmitter together with an external modulator. The receiver is composed of a 3.5 dB low-noise amplifier (LNA) with a high gain of 27 dB, gain-boosted envelope detector, and baseband amplifier. The transmitter and receiver amplifiers are implemented with a highly isolated ground between each stage in order to prevent oscillations even at the high gain. The communication system with the STNO achieves an 11.8 Mb/s wireless data transmission over 1 m, with a power consumption of 41.4 mW. The implemented transmitter and receiver occupy 2.34 and 4.08 mm², including all of the pads, respectively. The proposed system achieves the highest data rate with the lowest power consumption compared to those of the previous state-of-the-art STNO-based wireless communication systems.