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The International Telecommunication Union (ITU) has assigned the W-band for the downlink and uplink of satellite communications systems. This was highly necessary because the capacities provided by the new generations of highthroughput satellites (HTS) are in the order of Tbit/s, both uplink and downlink, requiring wider bandwidths. The Wband, together with the Q-band, will be employed by the feeder links of the next generation of HTS.The Q-band is already under detailed analysis (e.g. Alphasat TDP5 [1]) and is being used by the first satellites. However, the W-band lacks real measurements between space and ground to get an accurate propagation channel model. ESA has started the initiative for the exploration of this band by giving to the consortia composed of VTT, KuvaSpace, LCT, Fraunhofer, the University of Stuttgart and with the project lead by JOANNEUM RESEARCH the opportunity to build and operate a 3U CubeSat which transmits beacons at 75 GHz and 37.5 GHz, both with left and right-hand circular polarizations. This system allows to derive the complete transfer matrix and the frequency scaling relation between the two bands.The W-CUBE satellite was launched in June 2021 and soon afterwards a 75 GHz beacon signal was received, for the first time worldwide, from space to ground. In this presentation we describe the satellite payload architecture and the methods to measure the beacon on ground. First propagation measurement results are presented, allowing to perceive the different attenuation between W- and Q-bands. Challenges faced throughout a wave propagation campaign with LEO satellites are described. The possible continuation of the CubeSat operations and measurement campaign beyond 2 years up to 4 yearsare under discussion with ESA.

According to an example aspect of the present invention, there is provided antenna array comprising: a plurality of parallel antenna elements arranged on a printed circuit board laminate comprising a flexible substrate layer on a rigid substrate layer comprising portions specific to one or more antenna elements, said flexible substrate layer comprising a feed network, wherein the rigid substrate layer is configured movable between a first arrangement of the portions of the rigid substrate layer, where the antenna array has a planar form, and a second arrangement of the portions of the rigid substrate layer, where the antenna array is curved around one or more axes.Patent family as of 22.12.2021EP3711114 A1 20200923 EP20180793700 20181008 FI128822 B 20201231 FI20170006018 20171115 FI20176018 A 20190516 FI20170006018 20171115 US2020335847 AA 20201022 US20180764002 20181008 WO19097109 A1 20190523 WO2018FI50718 20181008Link to current patent family on right

A probe apparatus of a millimeter or submillimeter radio frequency band comprises transition layers (104, 106) having 5 outermost layers (110, 116) on opposite surfaces of the probe apparatus. An internal transition cavity (114) extends through the transition layers (106, 108) for guiding electromagnetic radiation within the probe apparatus (100). A probe layer (108) disposed between the transition layers (104, 106), the probe 10 layer (108) having a lateral transmission line (118) for interacting with the electromagnetic radiation guided by the internal transmission cavity (114).

The new services available through smart devices require very high cellular network capacity. The capacity requirement is expected to increase exponentially with the forthcoming 5G networks. The only available spectrum for truly wideband communication (>1 GHz) is at millimeter wavelengths. The high free space loss can be overcome by using the directive and beam-steerable antennas. This paper describes a design and the measurement results for a lens antenna system for E-band having 2-D beam-steering capability. Continuous beam-switching range of about ±4°*±17° is demonstrated with the lens having the maximum measured directivity of 36.7 dB. Link budget calculation for backhaul application using the presented lens antenna system is presented and compared with the measurement results of the implemented demo system.

Traffic safety can be improved by detecting the road surface condition using automotive radar. This paper describes two 24 GHz measurement systems for investigating the backscattering properties of different asphalt surfaces e.g. dry, wet and icy surfaces. The first system is used for measurements in a controlled environment and the second one is installed into a test vehicle. Measurement results from dry, wet and icy asphalt are presented together with results obtained from asphalt covered with tree leaves. The ultimate objective of the road condition detection radar is to estimate the road surface friction.

Imaging at submillimetre-wave (SMMW) frequencies is of considerable interest for security applications due to potentially superior performance at longer stand-off ranges in comparison to mm-wave imaging thanks to reduced diffraction. We have demonstrated passive broad-band video rate imaging system operating at a centre frequency of about 600 GHz, capable of 10 frames/second imagery of a 2 m * 1 m field-of-view at a stand-off distance of 5 meters. In addition, a multi-band system centred around 250, 450 and 720 GHz will be discussed. Multi-band imagery is interesting given its potential for rudimentary materials differentiation, a capability that would substantially benefit e.g. security imaging applications. The passive imaging activities are complemented by activities towards developing rapid electronic beam steering capability for imaging submm-wave radars. Results from two projects aiming at constructing such beam steering systems at 120 GHz and at 650 GHz are presented.

Low cost millimetre wave modules are needed for emerging 60 GHz applications such as high speed wireless communications and millimetre wave identification (MMID). All applications require high performance antenna arrays to overcome the high propagation losses. Two alternative antenna array designs on a low cost substrate (Taconic Taclamplus) are presented and analysed in this paper. The arrays are manufactured using standard printed circuit board (PCB) technology and have measured gains of 18 dBi and 23 dBi. The operational bandwidths are about 2 GHz around the center frequency. Transmitter and receiver modules based on the developed antenna arrays are also presented

In high frequency circuit boards PTFE is widely used as a substrate material. It offers very low dielectric constant and low losses. However, it is relatively expensive to fabricate, making the cost of PTFE laminates high. In addition PTFE-based circuit boards are composite materials with glass fiber reinforcement and thus not isotropic. Glass fiber also increases losses compared to raw PTFE. We have developed a new proprietary thermoplastic substrate especially for high frequency circuit boards. This polyphenylene ether (PPE) based substrate offers a low dielectric constant (dk), 2.55, and low dielectric loss (df), 0.002, in 1 to 5.5 GHz frequency range. It is unfilled, which makes the properties both isotropic and completely homogeneous throughout the substrate. This new material can be processed by typical thermoplastics processing methods, such as film and sheet extrusion and injection molding. Among thermoplastics, PPE is inherently low burning material and it can be easily made flame retardant (V0). However, the addition of flame retardant was found to slightly increase the dielectric loss at high frequencies. This plastic material exhibits a high glass transition temperature, Tg, around 200°C. This also gives the highest short term use temperature. There is no crosslinked structure to support the substrate above Tg. Processes requiring higher temperatures, such as conventional lead free reflow soldering or wave soldering can not be used. Because of the very good dielectric properties the material is intended for high frequency applications where the number of required solder connections is limited. One of these is a broadband base station antenna. The performance of this new material as a UMTS/WCDMA antenna for 1.92 - 2.17 GHz frequency band was evaluated with very promising results. First, a patch antenna was designed based on simulations and then the demo antenna was built. The measured performance coincided well with the simulation data. Design of a full size base station array antenna demonstrator is also presented

A design of a stacked microstrip patch antenna and a 16-element array on Ferro A6-M LTCC operating at W-band is presented. A parasitic patch is added on LTCC substrate to increase bandwidth. The stacked configuration is designed by using an equivalent circuit together with EM simulators. The manufactured antenna array is integrated with a WR-10-to-microstrip-line transition to facilitate RF testing. The S-parameters are measured on a probe station and radiation pattern testing is done using a WR-10 excitation in anechoic chamber. The array of size 9.3 mm * 9.3 mm * 0.4 mm has the measured maximum gain of 14.2 dBi at 84 GHz and gain higher than 11.2 dBi between 78.5 GHz and 98.5 GHz which results as ?3-dB radiation bandwidth of 23%. The antenna efficiency of the array is 48% at the highest.

In this paper, we present a fully automatic radiation pattern measurement setup for 60 GHz LTCC antennas. First, a detailed description of the mechanical and the RF parts of the set-up is provided. Then, the 3D radiation pattern measurements of several probe-fed antennas realized on a Low Temperature Co-fired Ceramic (LTCC) substrate are compared with simulations and measurements done at VTT when the antennas are fed by a connector. These experiments demonstrate the possibility to accurately measure the radiation of probe-fed antennas with distinct directions of radiation.

In this paper, a design of a 77 GHz beam-switching antenna on Ferro A6-M LTCC is presented. The antenna consists of three high-gain end-fire type antenna elements pointing at different directions. One element is active at a time and the appropriate element is selected using a commercial SP4T GaAs pin-diode switch. A design of a transition from a WR-10 waveguide to a microstrip line for radiation pattern testing purposes is also described. The transition covers almost the entire waveguide W-band and the measured reflection coefficient is below -10-dB between 77 GHz and 110 GHz. The total loss of the transition is only 1 dB at the maximum. Measured maximum gain of 9.2 dBi and a -3-dB beamwidth of about 40° are achieved for a single antenna element. Simulated radiation efficiency is 89 %. Beam switching between three different directions is demonstrated with radiation pattern measurements at 78 GHz. Good agreement is achieved between the simulated and measured results. The presented antenna is a very promising candidate for high data rate short-range millimetre-wave applications.

A wideband 60 GHz end-fire antenna element and a 1*4 array suitable especially for mobile devices have been developed. For the single antenna, the measured |S11| is below -7 dB between 53-68 GHz and below -10 dB in the frequency ranges of 53-59 GHz and 65-68 GHz. The measured gain is 3.1.7.1 dBi between 55-64 GHz. For the array, the measured -10-dB frequency band is from 52 GHz up to 68 GHz. The measured gain is 7.0.9.5 dBi between 55-64 GHz. The antennas are manufactured on LTCC ceramic process and can be integrated with a radio module or flip-chip mounted on a mobile device circuit board. The size of the manufactured compact antenna element is only 3*4*0.27 mm3. The array occupies 12*5.5*0.27 mm3 of space.

Radiospektrissä on 60 gigahertsin tuntumassa lisensoimaton taajuuskaista, joka soveltuu nopeisiin lyhyen kantaman yhteyksiin. Alue soveltuu mainiosti esimerkiksi HDTV-videosignaalin langattomaan lähisiirtoon. Tämän taajuusalueen WPAN-linkkien standardointitilanne on edistynyt ripeästi ja uusia sovelluksia sekä tekniikoita on kehitetty erityisesti mobiililaitteille.

Recent developments in the low temperature cofired ceramic (LTCC) technology have enabled the integration of passive components including antennas in a cost-effective package up to the millimetre-wave frequencies. Suitable antenna types for the LTCC integration are, for example, microstrip dipoles, slot antennas, and various types of microstrip patch antennas [1,2]. In this paper, the design and manufacturing of an aperture-coupled microstrip line-fed microstrip antenna (ACMPA) and a slot-coupled coplanar waveguide-fed microstrip antenna (SCMPA) on LTCC substrate are presented. Also, the material characterisation of Ferro A6S LTCC system with method based on ring resonators is shown. The return loss of -10 dB or better is achieved for the antennas within 3.4. 6.6% impedance bandwidth. Our studies show that functional antennas can be fabricated with standard LTCC process and materials even for the 60 GHz frequency band.

Computer-generated holograms can be applied in space terahertz technology; they are particularly suitable as focusing elements in compact test ranges, for example, in testing of high-gain antennas and measuring radar cross section (RCS) of scaled models. Radio holograms have also been demonstrated in other millimeter- and submillimeter-wave beam-shaping applications, such as the creation of non-diffracting mm-wave Bessel beams, mm-wave vortices, and custom-designed beam patterns. During summer 2003 we built a temporary measuring facility at the High Voltage Institute of the Helsinki University of Technology to test the ADMIRALS antenna built by EADS Astrium. The measurement results obtained at 322 GHz are so promising that we are currently proposing a hologram CATR test for the Planck telescope at 500 GHz.

A novel inline type millimeter wave MEMS power sensor is presented. The electrostatic force due to the ms voltage across the transmission line conductors displaces the sensor electrode, and the movement can be detected capacitively. RF properties of the sensor can be optimized so that S11 is better than -30 dB and S21 less than 0.1 dB up to 45 GHz with a power resolution of -37 dBm.