Jianxun Zhu

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This article focuses on a new type of wireless devices in the domain between RFIDs and sensor networks—Energy-Harvesting Active Networked Tags (EnHANTs). Future EnHANTs will be small, flexible, and self-powered devices that can be attached to objects that are traditionally not networked (e.g., books, furniture, toys, produce, and clothing). Therefore,(More)
A 0.2-1 GHz RF front end with a harmonic-rejecting N-path filter (HR-NPF) features tunable narrow band filtering as well as high attenuation at the 3rd and 5th order LO harmonics at the LNA output. The B1dB-CP is -2.4dBm at a 20MHz offset, and remains high at the 3rd and 5th LO harmonics thanks to the HR-NPF configuration. The reverse isolation of the LNA(More)
This paper focuses on a new type of wireless devices in the domain between RFIDs and sensor networks – Energy Harvesting Active Networked Tags (EnHANTs). Future EnHANTs will be small, flexible, and self-powered devices that can be attached to objects that are traditionally not networked (e.g., books, toys, clothing), thereby providing the infrastructure for(More)
Summary form only given. A low noise amplifier is presented that uniquely achieves wide-band input matching and good low-frequency noise performance at the same time. Its topology is a hybrid of distributed amplifier and a common-source common-gate noise-canceling amplifier. The proof-of-principle prototype in 65nm CMOS operates from DC up to 9.5GHz with(More)
Energy Harvesting Active Networked Tags (EnHANTs) are a new class of devices in the domain between RFIDs and sensor networks. EnHANTs will be small, flexible, and energetically self-reliant. Their development is enabled by advances in ultra-low-power ultra-wideband (UWB) communications and in organic semiconductor-based energy harvesting materials. In this(More)
A field-programmable (FP) low-noise amplifier (LNA) with interferer-reflecting (IR) loop is introduced. The user can program its gain, noise figure, linearity and power consumption during operation. The IR loop uses a frequency-selective shunt-shunt feedback around the noise-canceling LNA to reduce the input impedance out of band and to suppress the input(More)
<i>Energy Harvesting Active Networked Tags (EnHANTs)</i> will be a new class of devices in the domain between RFIDs and sensor networks. Small, flexible, and energetically self-reliant, EnHANTs will be attached to objects that are traditionally not networked, such as books, furniture, toys, produce, and clothing. More information about the EnHANTs project(More)
EnHANTs will be small, flexible, and self-powered devices that will be attached to objects that are traditionally not networked (books, furniture, clothing), thereby enabling various tracking applications (more details are available at enhants.ee.columbia.edu). We demonstrate a small testbed of En- HANTs prototypes. The prototypes communicate using(More)
Considering that ordinary ZigBee based systems operate at a rate of 250kbps, which imposes various limitations on their applications, and that there are 16 independent channels at 2.4GHz, this paper presents a novel approach of FPGA controlled, ZigBee protocol based multi-frequency high speed wireless Ad Hoc network. The system employed five individual(More)
A field-programmable noise-canceling wide-band receiver front end with high performance LNTAs is presented. The common-source (CS) and common-gate (CG) LNTAs are split into several cells whose bias point can be individually programmed in class AB or C yielding a highly linear hybrid class-AB-C LNTA. The 40nm LP CMOS receiver prototype can be programmed on(More)