Retour au site du LAAS-CNRS

Abstract

A study of the feasibility of a wide band double balanced resistive mixer in the 60 GHz band is done. The device is implemented in a 65nm CMOS technology process. In this paper an approach to design an optimized version of the mixer in terms of the principal figures of merit: conversion loss, port to port isolation and noise figure is shown. The mixer will be a part of an homodyne downconversion system. The conversion loss is 6.9±0.2dB around 60GHz with a  5dBm of LO drive. The port-to-port isolation for the LO feed through is better than 41dB. The noise figure is 8.39dB. The power dissipation for the mixer depends on the LO buffer that increases the input LO power. Its power consumption is 15mW

Mots-Clés / Keywords

Abstract

In radio frequency integrated circuits using a low resistivity silicon substrate, spiral inductors show advantages in performance and size with respect to transmission lines, even at frequencies as high as 60 GHz. In order to verify simulation results and build accurate models, test inductors need to be fabricated and characterized very accurately. This implies the precise determination of the effective quality factor Qeff and the measurement of the inductance L within a few pico-Henrys. This paper reviews suitable on-chip calibration and deembedding techniques and proposes a technique that uses distributed and lumped elements to model the error two-ports. These elements also take into account the contact impedance. The results obtained by this novel de-embedding approach are compared to results of the other discussed methods and to simulation results. The obtained agreement proves the suitability of the proposed method for characterization of millimeter-wave inductors.

Mots-Clés / Keywords

Abstract

This letter presents a new and efficient digital baseband architecture for impulse radio ultra wideband (IR-UWB) transceivers with reconfigurable capacities for wireless sensor network (WSN) applications. An implementation is done on FPGA for validation by measurements. It achieves the highest data rate and the largest number of operating modes for an IR-UWB reconfigurable transceiver, to the best of the author's knowledge. Measurements demonstrate reconfigurability in data rate (from 4 to 125 MBits/s), chip duration (from 8 to 32 ns), pulse duration (from 1 to 4 ns), bit duration (from 8 to 256 ns), processing gain (from 1 to 8 pulses/bit), occupied bandwidth, radio range, BER performance, synchronization accuracy (from 0.5 to 4 ns), pulse amplitude, transmitted power density, duty cycle (from 3 to 50 %), power consumption, spectrum occupation, and maximum supported UWB channel delay spread (from 4 to 31 ns).

Mots-Clés / Keywords

Abstract

In radio frequency integrated circuits (RFICs) that use a low resistivity silicon substrate, spiral inductors show advantages in performance and size with respect to transmission lines, even at millimeter-waves (mm-waves). Design guidelines to create mm-wave inductors and equivalent circuit models describing them exist in literature. However, these models need to be parametrized either from teststructure measurement or electromagnetic (EM) simulations. This paper complements previous work by discussing problems that arise when trying to accurately determine thespiral's parameters as inductance and quality factor. Firstly, it provides guidelines for obtaining accurate and consistent results using different kinds of EM simulators. Secondly, the issue of accurately measuring the fabricated inductors by deembedding test structure parasitics is discussed. The results obtained from measurements are compared to the simulation results of an inductor test structure, confirming the validity of the considerations before.

Abstract

This paper presents an approach to RF MEMS capacitive shunt switch design from K band up to W-band, based on the scalability of the RF MEMS switch with frequency. The parameters of the switch's equivalent circuit model also follow scaling rules. The measurement results of the fabricated switches show an excellent agreement with simulations which allow to validate the MEMS model in the entire band from 20 GHz up to 94 GHz. This model is going to be used in phase shifter circuit design for antenna array applications. First 60 GHz phase shifter results are also reported here.

Mots-Clés / Keywords