The European Space Agency's Planck satellite, launched on 14 May 2009, is the third-generation space experiment in the field of cosmic microwave background (CMB) research. It will image the anisotropies of the CMB over the whole sky, with unprecedented sensitivity ( ~ 2 × 10-6) and angular resolution (~5 arcmin). Planck will provide a major source of information relevant to many fundamental cosmological problems and will test current theories of the early evolution of the Universe and the origin of structure. It will also address a wide range of areas of astrophysical research related to the Milky Way as well as external galaxies and clusters of galaxies. The ability of Planck to measure polarization across a wide frequency range (30-350 GHz), with high precision and accuracy, and over the whole sky, will provide unique insight, not only into specific cosmological questions, but also into the properties of the interstellar medium. This paper is part of a series which describes the technical capabilities of the Planck scientific payload. It is based on the knowledge gathered during the on-ground calibration campaigns of the major subsystems, principally its telescope and its two scientific instruments, and of tests at fully integrated satellite level. It represents the best estimate before launch of the technical performance that the satellite and its payload will achieve in flight. In this paper, we summarise the main elements of the payload performance, which is described in detail in the accompanying papers. In addition, we describe the satellite performance elements which are most relevant for science, and provide an overview of the plans for scientific operations and data analysis.

This letter presents a novel reconfigurable, high-efficiency class-F power amplifier (PA) structure, using a commercial GaN-HEMT, that achieves dual-band configuration not only at the fundamental frequency but also at the harmonics. With a proper harmonic tuning structure, the need for an extra filtering section is eliminated, resulting in a high dual-band efficiency with a reduced number of components and size. The reconfigurable structure uses commercial single-pole-double-throw (SPDT) and single-pole-single-throw (SPST) MEMS switches optimally placed on the stubs to select between 900 and 1800 MHz. The reconfigurable PA achieves a measured power-added efficiency (PAE) of 69.5% and a power gain of 13.6 dB while delivering an output power of 39.1 dBm at 900 MHz. At 1800 MHz, the amplifier achieves a PAE of 57.9%, a power gain of 10.5 dB, and an output power of 38.5 dBm.

This paper provides a rigorous study of the causes and physical origins of intermodulation distortion (IMD) in RF microelectromechanical systems (MEMS) capacitors, its analytical dependence on the MEMS device design parameters, and its effects in RF systems. It is shown that not only third-order products exist, but also fifth order and higher. The high-order terms are mainly originated by the nonlinear membrane displacement versus applied voltage and, in the case considered in this study, with an additional contribution from the nonlinear dependence of the reflection coefficient phase on the displacement. It is also shown that the displacement nonlinear behavior also contributes to the total mean position of the membrane. In order to study these effects in depth, an analytical frequency-dependent IMD model for RF MEMS based on a mobile membrane is proposed and particularized to the case of a MEMS varactor-a device for which IMD can be significant. The model is validated, up to the fifth order, theoretically (using harmonic balance) and empirically (the IMD of a MEMS varactor is measured). To this end, a two-tone IMD reflection measurement system for MEMS is proposed.

A novel reconfigurable CMOS class-F power amplifier (PA) at 2.4 GHz is proposed in this paper. It is able to match the output load variations mainly due to the effect of hand and head on a mobile phone. The effect of load variation on power-added efficiency (PAE), output power, and distortion is compensated by reconfiguring the output network using an impedance tuner. The tuner controls the output matching at fundamental frequency without affecting the class-F harmonic tuning up to 3 ^rd harmonic. To the best of our knowledge, this is the first design of a CMOS class-F PA addressed to compensate the effect of load variation. Measurement results for 50 Ω load impedance show a maximum PAE of 26% and maximum output power of 19.2 dBm. The measured total harmonic distortion is 4.9%. Measurement results for load values other than 50 Ω show that PAE increases from 6.5% (not-tuned PA) up to 19.9% (tuned PA) with the same output power (19.2 dBm). Tuning also reduces the adjacent-channel leakage ratio by 5 dB and the spectral regrowth of a Wi-Fi signal at the PA output. The size of the fabricated chip is 1.6 mm × 1.6 mm.

This paper presents an electrothermally actuated lateral resistive-contact switch for application to low-gigahertz-band communication systems. It was manufactured on a standard low-resistivity substrate, and its RF performance was improved by suspending the structures 25 ¿m from the substrate, which is a strategy for future integration with active devices in the system-on-chip concept. Measured insertion losses are -0.26 dB at 1 GHz and -0.65 dB at 6 GHz, return losses are -29 dB at 1 GHz and -25 dB at 6 GHz, and isolations are -52 dB at 1 GHz and -26 dB at 6 GHz. The device is driven by a metal electrothermal actuator, which achieves large displacements and contact forces at much lower temperatures than traditional polysilicon electrothermal actuators. The RF power handling characteristics are also addressed and measured.