A 71GHz RF energy harvesting tag with 8% efficiency for wireless temperature sensors in 65nm CMOS

A 50–60 GHz mm-Wave Rectifier With Bulk Voltage Bias in 65-nm CMOS

“…1. V B is the bulk bias point, C pad and L in form the input matching network, C c is the coupling capacitor, C p is the inter-stage DC capacitor [1], [7].…”

“…Wireless power transfer with an on-chip wireless power receiver is a solution to achieve such a highly integrated sensor node [1]. At mm-wave frequencies, it is even possible to integrate the antenna on chip, which can further shrink the size of sensor nodes.…”

“…Compared with discrete components, the silicon IC based solution is a much more compact solution for IoT. In [1], the rectifier operates at 71 GHz and employs a 3-stage inductor peaking technique, achieving a sensitivity of 7 dBm for a 1 V output DC voltage. In [3], a 60 GHz rectifier using a load-capacitor shielding technique shows 2 dBm sensitivity for a 1 V output voltage.…”

“…In this method, the threshold voltage of MOSFETs in the main rectifier is modulated by biasing their bulk voltage, which improves the rectifier sensitivity and efficiency. Compared to the inductor peaking method [1] or local threshold voltage modulation technique [2] in CMOS technology, the circuit proposed in this letter achieves better sensitivity and efficiency while maintaining a compact size. The work achieves −10 dBm input sensitivity at 52 GHz with 1 V DC output voltage.…”

W-Band CMOS on-chip energy harvester and rectenna

“…Till now, the highest frequency of rectifier operation in CMOS is 70GHz [1]-[5]. In [1], [2] the authors present an inductor peaked rectifier at 62GHz and 71 GHz with 7% and 8% efficiencies respectively and in [3] a rectifier at 45GHz with 1.2% efficiency with 2dBm input power has been reported. In [4] a 60GHz RF-DC power converter demonstrates a power conversion efficiency of 28% using on chip probing.…”