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This article presents a 2.4-GHz 65-nm CMOS fully integrated nonlinear mixer-first receiver (RX) for the Internet of Things (IoT). To power efficiently improve the in-band interference resilience, we propose an inverter-based envelope-biased low noise amplifier (IBEB-LNA), which exploits dynamic biasing voltage generated from its input signal envelope to suppress the interferer in the amplitude domain. The achievable carrier-to-interference ratio (CIR) at ±3 and ±5 MHz is −45/−59 and −66/−65 dB, respectively. The proposed RX is suitable for ON–OFF keying (OOK) modulation with a 307-kb/s data rate, and the corresponding sensitivity is −83 dBm for keeping 0.1% bit error ratio (BER). The total power consumption is 2.05 mW.

This article presents a 13.56-MHz wireless power and data transfer receiver for implantable biomedical devices. To avoid the efficiency reduction of energy harvesting caused by the large amplitude modulation (AM) modulation depth (MD), and maintain low-power consumption for data receiving, an envelope-detector-based receiver with shifted limiters is designed for signal demodulation. The detectable MD is as low as 0.1%. Moreover, a dynamic impedance matching controller is proposed to adjust the input impedance of the rectifier automatically and thus optimize the power conversion efficiency (PCE). By using these techniques, when keeping the bit error rate (BER) of the proposed receiver to 10−3 for 100-kb/s data rate in the wireless amplitude shift keying (ASK) data receiver, the effective PCE of the corresponding wireless power receiver can be up to 75.4%.

Improving interference robustness in ultralow power (ULP) receivers (RXs) is a big challenge due to their low power budget. This paper presents an envelope detector based 915 MHz 10 kb/s ULP RX, which is fabricated in 65 nm CMOS process for wireless sensor networks and Internet of Things. Two power-efficient techniques, transmitted-reference and shifted limiter, are proposed to improve the interference robustness. The RX sensitivity is between −61 and −76 dBm. The maximum in-band signal-to-interference ratio at ±1 MHz offset is up to −50 dB while just consuming 175 $\mu \text{W}$ power from a 1 V supply.