The preliminary results concerning the design and test of a compact substrate-embedded Ka-band filter based on Air-Filled Substrate-Integrated-Waveguide (SIW) technology are presented in this paper. The proposed solution consists of a 5th order in-line bandpass filter to be placed in front of the Low-Noise-Amplifier in multibeam satellite payloads. The insertion-loss represents the main driver, as well as the rejection of the transmitting signal and volume occupation. In fact, the dimensions of the RF modules are often limited by the physical sizes of the filters, which are generally based on bulky waveguide concepts. SIW technology represents an optimal compromise in terms RF performance, cost, size, and manufacturability thanks to the combination of planar and non-planar structures. The peculiarity of proposed solution concerns its fully integration inside PCB support where also other RF modules are placed. This allows for important benefits in terms of compactness and simpler architecture since complex RF interfaces can be avoided between filter and other components. The feasibility of proposed solution has been demonstrated through the measurement of two prototypes which show excellent results in terms of quality-factor and good out-of-band rejection.

The design and test of an E-band (81–86 GHz) down-converter mixer for satellite communications is given in this contribution. The selected topology is the sub-harmonically pumped mixer. The MMIC is designed with VMS's 100 nm GaAs pHEMT technology. Characterization of the mixer shows 13–16 dB conversion loss, 40 dB rejection to LO pump and other intermodulation products at IF port, and simulated IIP3 of +14 dBm.

This paper presents the design and the fabrication of a compact Ka-band dielectric cavity filter, manufactured in 3D-printed alumina technology. The goal is to achieve a flat in-band insertion loss, keeping constrained the device size. A 4th order and a 8 th order cavity filters with 4 transmission zeros were designed and tested. The 8 th order filter were designed using dual mode cavities in order to introduce additional transmission zeros without increasing the manufacturing complexity of the ceramic part. The filter is fabricated on low tanδ alumina which allows to achieve relatively high Q factor reducing the size of the device. The resonators exhibit a relatively- high unloaded Q-factor up to 800 which allows to increase the flatness in the operative bandwidth (27GHz-29.4GHz, FBW 8.5%). The selection of the material and filter geometry determine a very low occupation area (14×25mm 2 ). The cavity filter has been mounted on alumina substrate to improve the thermal stability of the joint. The device demonstrates good robustness to thermal variations in the range between −10 and 70°C.

This paper presents the design and test results of a W-to Ka-band Frequency Converter (Docon) for satellite communication application developed in Thales Alenia Space Italia (TAS-I) under a contract with the European Space Agency (ESA) operating in the frequency ranges from 81–86 GHz to 17.2-20.2 GHz. The Docon features 65 dB of conversion Gain compensated in temperature, a Noise Figure of 5.5 dB at ambient temperature, including the input isolator, and linear amplification of the useful multicarrier signal resulting in a total Third Order Intercept point (OTOI) of +30 dBm. The output spectrum is practically spurious-free in band, only showing the residual out-of-band LO signal at a level well below −40 dBm. Docons are key elements in satellite communications payloads, allowing the translation of uplink frequency to the downlink user frequency band. The rationale for exploiting the W - band is the larger and continuous bandwidth at disposal, roughly twice the one currently available in Q/V-band. Consequently, the number of user beams associated with a single gateway is almost doubled. Several custom MMICs have been developed for this project by using the space qualified PH10 GaAs process from UMS. To the best of the knowledge of the authors, this is the first Docon operating in W-band ever realised for space applications

This paper describes the design and experimental results of a DP4$T$ MMIC switch to be used as a building block for high-order compact and scalable Ka-band Switch Matrices. Two variants of the MMIC have been designed and optimized to be used in bare-die form, within hermetic complex modules, and in QFN plastic package solution, to be assembled in PCB based architectures. Both chips are manufactured on a European 0.15 $\boldsymbol{\mu}\mathbf{m}$ GaN/SiC HEMT technology for a total die area of 4x4 mm2. Good equalized insertion losses of about 2.5 and 3.5 dB, for bare-die and packaged variants respectively, were measured along all possible active paths. A minimum isolation level of 30 dB and a return loss better than 15 dB at all the RF ports were achieved for both circuits. The MMICs are fully compliant with the space deratings.

This paper provides an overview of some of the recent technology developments and R&D activities supported by the European Space Agency for next generation satellite communication payloads based on active antennas and onboard digital processing functions. In particular, recent technology developments on active antennas for LEO, MEO and GEO missions, including HPA MMICs, are presented. An introduction to R&D activities in the area of digital signal processing and digital beamforming, as well as in signal processing techniques for MIMO satellite systems is also provided. Possible future satellite systems supporting 5G are also introduced.

High-Q filters are a critical component in many systems. However, high-Q filters require very low-loss passive elements that are not compatible with monolithic technology. Therefore, filters are often implemented as off-chip components. Tunable high-Q filters require even larger space and weight, and are usually quite bulky. Active filters have been proposed in the past for a monolithic implementation. However, it is not easy to fulfil such requirements as a high dynamic range, low power consumption, low noise, wide tunability, stability, etc. With this study, we propose a survey of the main solutions presented in the literature, investigating the fulfilment of all or most requirements and their potential applications and feasibility, to be used in practical applications.

This paper presents the design and the fabrication of a compact and robust Ku-band differential bandpass filter, manufactured in thin-film on alumina. The 3-port device includes a balancing network which converts a single-ended input into a differential output. The goal is to achieve a flat in-band Insertion loss, keeping constrained the device size. An 8th order lossy filter with 2 transmission zeros is synthetized using resistive cross-couplings to increase the IL flatness at the expenses of the absolute insertion loss. The balanced to unbalanced conversion is performed by a microstrip Lange coupler and a wideband Schiffman phase shifter. The device exhibits 0.7dB IL flatness in the operative bandwidth 12.75GHz-14.8GHz (FBW 14.5%) and an overall footprint of 14x26mm2. The device demonstrates also high robustness to thermal variations in the temperature range between -10 and 70°C.

ESA's Soil Moisture and Ocean Salinity (SMOS) mission was launched 2 Nov 2009 and, to date, is still in good health, providing valuable L-band observations of the Earth surface [1]. A number of products are obtained from these, including thin sea ice [2], frost/thaw soils [3], high winds [4], ocean surface wind [5] and Sun brightness temperature [6], besides the main mission measurements of soil moisture and sea surface salinity [7] [8]. This paper deals with the description and early results of some technology activities conducted by ESA applying the lessons learnt by SMOS and in preparation of an advanced L-band radiometer mission.

Presents information on the MMTS European Microwave Week.

In this paper the design and first experimental results of surface mountable bandpass filters in the L- and C- bands are presented. Used for frequency converters in High Throughput Satellite (HTS) systems, the L-band filter is centred at 960MHz with 500MHz bandwidth (FBW=52%) while the C- band filter is centred at 5.35GHz with 2.5GHz bandwidth (FBW=47%). The results presented in this paper are the outcomes of an ESA ARTES AT project called SUMO (`Surface Mountable Filters for Frequency Converters'). Pre-distorted filter characteristics are proposed for both L- and C-band architectures in order to obtain flatter in-band responses (IL- flatness<; 1dB). Concerning the L-band filter, two solutions are proposed and compared by combining commercial SMD lumped components with customized LTCC elements. About the C-Band filter, a distributed solution based on edge-coupled quarter- wavelength resonators is proposed. Before the fabrication of the final engineering models, multiple prototypes have been designed in order to test the LTCC fabrication process and materials used for LTCC architectures. The results of these preliminary analyses are shown in this paper.

A 12×12 Switch Matrix Unit featuring silicon RF MEMS assembled on LTCC boards has been developed under a Contract with the European Space Agency (ESA) for satellite communication application. The Switch Matrix is a complete Engineering Model unit, housed in a mechanical box in aluminum with RF coaxial connectors and DC connectors for powering and commanding. To the authors' knowledge, it is the first complex equipment realized in Europe exploiting the advanced features of the RF MEMS and multilayer LTCC technology to achieve a significant mass and size reduction. Full wave simulations of entire structure are reported, as well as test results. Their agreement is good up to the satellite downlink C-band (3.7-4.2 GHz). An insertion loss of -20dB, return loss of -10dB and isolation of 40-45dB have been measured. The matrix is passive (not provided with amplifiers), having a DC power consumption of less than half watt due to the digital command circuitry.

This paper reports on the design of a new power cell dedicated to Ku-band power amplifier (PA) applications. This cell called “`integrated cascode'” has been designed in order to propose a strong decrease in term of circuit size for Power Amplifier (PA). The technology used relies on 0.25-μm GaAs Pseudomorphic High Electron Mobility Transistors (PHEMT) of United Monolithic Semiconductors (UMS) foundry. A distributed approach is proposed in order to model this power cell. The challenge consists to obtain, with a better shape factor (ratio between the vertical and horizontal sizes of the transistor), the same performances than a single transistor with the same gate development. In order to design a 2W amplifier, we have used two 12×100 μm transistors. Cascode vertical size is 413 μm whereas a transistor with the same gate development exhibits a vertical size of 790 μm. Therefore the shape factor is nearly one as compared to a shape factor of 4 for a classical parallel architecture. This new device allows to decrease the MMIC amplifier area of 40 % compared with amplifier based on single transistors.

A large band SPDT (single‐pole double‐throw) switch based on a very advanced RF‐MEMS switch technology for redundancy schemes are presented. This device allowed to reach state‐of‐the‐art working bandwidth (DC‐50 GHz) and RF performances (IL (Insection loss) < 0.8 dB, isolation > 25 dB, and RL > 20 dB). The 200 mm MEMS technology process has demonstrated a very good stability with very low dispersion (deviations < 0.05 dB for the IL and < 0.6 dB for the isolation over the entire wafer and frequency range). An accurate electrical equivalent circuit, modeling the SPDT in the DC‐65 GHz frequency band, has allowed to extract a contact resistance which is as low as 1.4 Ω. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:333–335, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27330

The charging of the dielectric used for the actuation in microelectromechanical system (MEMS) devices is one of the major failure sources for switches based on this technology. For this reason, a better understanding of such an effect is vital to improve the reliability for both ground and space applications. In this paper, the expected response of MEMS switches to unipolar and bipolar dc actuation voltages has been measured and modeled. Two configurations of MEMS switches, namely, an Ohmic series and a shunt capacitive one designed for microwave applications, have been studied as a test vehicle for charging effects related to the dc actuation pads. The recorded data have been interpreted mainly through the Poole–Frenkel effect due to charge injection when a high voltage is applied to the dielectric layer. Metal-Insulator-Metal (MIM) structures have been also considered as a complementary information for the response of the dielectric material.

The reliability of RF MEMS switches is typically reduced by charging effects occurring in the dielectrics. The aim of this paper is to discuss these effects, and to propose analytical and equivalent circuit models which account for most of the physical contributions present in the structure.

This paper presents recent development conducted in the area of RF packaging and interconnect technologies. An original concept of 3D silicon packaging including collective wiring process is proposed and applied to the design of an X-band T/R module demonstrator. An RF solder-less interconnect based on the CIN::APSE connecting system (CINCH ) has been developed to address the need of vertical transition in new generation of SAR active antenna.