Michael Libois

A 16mA UWB 3-to-5GHz 20Mpulses/s Quadrature Analog Correlation Receiver in 0.18/spl mu/m CMOS

A 3-to-5GHz quadrature analog correlation RX for UWB impulse radio draws 16mA at 20Mpulses/s, making it suitable for low-power low-data-rate applications. The RX is fully integrated in a CMOS 0.18mum process and comprises an LNA, quadrature LO generation and mixers, baseband filtering, an integrator, timing circuitry, and an ADC

A Fully Reconfigurable Software-Defined Radio Transceiver in 0.13μm CMOS

A fully reconfigurable SDR contains an RX, a TX, and 2 synthesizers for true multi-standard operation. A MEMS-enabled dual-band LNA proves the feasibility of switched antenna filtering for interference robustness. The baseband section is programmable in noise level and in bandwidth from 350kHz to 23MHz. The receiver has 6dB NF, -9dBm IIP3, and up to 90dB gain. Implemented in a 0.13μmum CMOS process, it draws 62mA to 120mA in RX mode and 56mA to 89mA in TX mode from a 1.2V supply.

A low-power radio chipset in 40nm LP CMOS with beamforming for 60GHz high-data-rate wireless communication

The link budget of multi-Gb/s wireless communication systems around 60GHz improves by beamforming. CMOS realizations for this type of communication are mostly limited to either one-antenna systems [1], or beamforming ICs that do not implement all radio functions [2]. The sliding-IF architecture of [3] uses RF phase shifting, which deteriorates noise performance.

A CMOS 100 MHz to 6 GHz software defined radio analog front-end with integrated pre-power amplifier

A Software-Defined Radio (SDR) analog front-end is presented that provides extensive programmability of LO generator, LNA, mixers, baseband filters and PPA, supporting various wireless communication standards while guaranteeing a near-optimal power/performance trade-off at any time. The circuit is integrated in a 0.13 mum CMOS technology with 1.2 V supply voltage. This transceiver covers the frequency range from 100 MHz up to 6 GHz by exploiting a flexible zero-IF architecture. The receive path achieves a Noise Figure of 4.8 dB at 174 MHz and 6 dB at 2.4 GHz. For a WLAN OFDM 64 QAM output, the transmitter achieves an EVM better than -29 dB for -0.5 dBm output power at 2.4 GHz and -3.1 dBm output power at 4.9 GHz.

A novel and low-cost analog front-end mismatch calibration scheme for MIMO-OFDM WLANs

This paper presents a novel and low-cost analog front-end gain and phase mismatch calibration scheme for MIMO-OFDM TDD WLAN systems with transmit-processing, where the complete channel reciprocity and calibration of the access point hardware is needed. It is shown by analytical derivations that the novel scheme has similar performance to that of the older scheme. The new scheme also has the advantage of lower implementation cost by removing the necessity of having a calibration transceiver. In addition, it is demonstrated that the new scheme can easily be extended towards an arbitrary number of multi-antenna transceivers.

Measurements and Analysis of Substrate Noise Coupling in TSV-Based 3-D Integrated Circuits

Silicon substrates can be strategically isolated or unified among tiers in a through-silicon-via (TSV)-based 3-D integrated circuit (IC) structure, for the suppression of intertier substrate noise coupling or the reduction of grounding impedance of silicon substrates as a whole, respectively. A two-tier 3-D IC demonstrator in a 130-nm CMOS technology was successfully tested and analyzed with respect to intra and intertier substrate noise coupling. Each tier in the stack includes digital noise source circuits (NSs) and substrate noise monitors, and embodies in-place measurements of substrate noise coupling. An equivalent circuit unifies power and substrate networks of the tiers and simulates the frequency-domain response of substrate noise coupling. Measurements and calculation with the equivalent circuit are consistent for frequency dependency of substrate noise coupling in a 3-D IC demonstrator. Intratier propagation is dominant, while intertier coupling is insignificant for low-frequency substrate noise components. Intertier coupling becomes comparable with and finally overwhelms intratier coupling as the frequency of substrate noise components increases. Substrate noise coupling in a multitier chip stack is strongly impacted by the parasitic capacitance of TSVs, while that coupling becomes predictable with the equivalent circuit of the entire stack.

An Integrated a-IGZO UHF Energy Harvester for Passive RFID Tags

We present an ultrahigh frequency energy harvester based on low temperature processed a-IGZO (amorphous indium-gallium-zinc oxide) semiconductor on a glass substrate. The harvester is composed of a dipole antenna, matching network, and a double half-wave rectifier and is capable of delivering more than 1 Vdc at a distance of 2 m from the transmitter antenna. In the proposed wireless system, this sensitivity corresponds to 2.75-m distance harvesting at 4-W (36 dBm) emitted power from a base station, which is within EPC regulations. The main element of the rectifier is the high-performance a-IGZO Schottky diode on glass, with a rectification ratio of 107 at ±1 V, a low threshold voltage of 0.6 V and a cutoff frequency of 3 GHz at 0 V bias.

Experimental Analysis of the Coupling Mechanisms Between a 4 GHz PPA and a 5–7 GHz

The coupling of the transmitted radio-frequency (RF) signal of the power amplifier (PA) in the sensitive voltage-controlled oscillator (VCO) remains a major problem for system-on-chip (SoC) design. Coupling between these two circuits may cause malfunctioning of the system. This paper analyzes the different coupling mechanisms between a 4 GHz prepower amplifier (PPA) and a 5-7 GHz LC-VCO designed in 0.13 mum technology. Different experiments are carried out to reveal the dominant coupling mechanisms. Insight into these mechanisms leads to the proposal of proper countermeasures.

LC

We present an energy harvester composed of a dipole antenna, matching network and a rectifier based on thin-film metal-oxide (amorphous Indium-Gallium-Zinc Oxide, IGZO) semiconductor Schottky diodes, operating at 868MHz. S-parameters measurements show that the integrated single IGZO Schottky diodes have a cutoff frequency over 1.8GHz at 0V bias. Large signal analysis of the integrated double-half wave rectifier shows a cut-off frequency of 1.1GHz. Our harvester generates 1.3V at 15 cm from an emitter emitting 15dBm at 868MHz.

-VCO

This paper presents, for the first time, a MEMS-enabled dual-band receiver front-end in 0.13-mum CMOS, which covers both 1.8-GHz and 5-6-GHz bands. A packaged MEMS series switch is used to tune the LNAs input impedance for narrow-band matching in each of these bands. The mixer of the front-end is a double-balanced folded Gilbert cell, which is followed by a programmable current-output stage. The front-end shows a measured gain of 45 dB and a NF of 4.2 dB at 1.85 GHz. The LNAs IIP3 is -9 dBm at 1.85 GHz. The front-end consumes 28 mA from a 1.2-V power supply