2.4 GHz BLE Receiver With Power-Efficient Quadrature RF-to-Baseband-Current-Reuse Architecture for Low-Power IoT Applications

• Main Authors: Beomyu Park, Kuduck Kwon
• Format: Article
• Language: English
• Published: IEEE 2021-01-01
• Series: IEEE Access
• Subjects: Active-type polyphase filter; bias-current sharing; Bluetooth low energy; current-reuse; image rejection ratio; IoT
• Online Access: https://ieeexplore.ieee.org/document/9410218/

In this paper, a 2.4 GHz Bluetooth low energy receiver employing a power-efficient quadrature RF-to-baseband-current-reuse architecture is presented for low-power low-voltage internet of things applications. The proposed quadrature RF-to-baseband-current-reuse RF front-end consists of a low-noise transconductance amplifier, an active-type polyphase filter-based quadrature generator, transimpedance amplifiers, and double-balanced current-mode passive mixers on a single dc current path. An input matching network is used to perform power-constrained simultaneous noise and input power matching and 1/<inline-formula> <tex-math notation="LaTeX">$f$ </tex-math></inline-formula> noise reduction in the RF and baseband domains, respectively. The quadrature RF signals are provided to the single-quadrature mixers through an embedded active-type polyphase filter-based quadrature generator. The implemented Bluetooth low energy receiver is composed of the RF-to-baseband-current-reuse RF front-end, IF amplifiers, two-stage passive-<italic>RC</italic> polyphase filter, and fifth-order Chebyshev-II <inline-formula> <tex-math notation="LaTeX">$G_{m}$ </tex-math></inline-formula> <italic>-C</italic> filters. The proposed design was fabricated using a 65-nm CMOS process and characterized primarily in the Bluetooth low energy operating frequency bands. The active die area of the implemented receiver was 0.85 mm², and the receiver drew a bias current of 1.41 mA from a nominal supply voltage of 0.8 V. The Bluetooth low energy receiver achieved a noise figure of 13.2 dB, conversion gain of 42 dB, image rejection ratio of more than 30 dB, and input-referred third-order intercept point of &#x2212;25 dBm.