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

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 mm(2), 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.