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We present GalaxAI - a versatile machine learning toolbox for efficient and interpretable end-to-end analysis of spacecraft telemetry data. GalaxAI employs various machine learning algorithms for multivariate time series analyses, classification, regression and structured output prediction, capable of handling high-throughput heterogeneous data. These methods allow for the construction of robust and accurate predictive models, that are in turn applied to different tasks of spacecraft monitoring and operations planning. More importantly, besides the accurate building of models, GalaxAI implements a visualisation layer, providing mission specialists and operators with a full, detailed and interpretable view of the data analysis process. We show the utility and versatility of GalaxAI on two use-cases concerning two different spacecraft: i) analysis and planning of Mars Express thermal power consumption and ii) predicting of INTEGRAL's crossings through Van Allen belts.

Elliptic curves are gaining momentum as scientists are continuously proving their security and performance. Pairings over elliptic curves are relatively new in the world of cryptography. Researchers are coming with new cryptographic usage of pairings for over ten years. ID-based cryptography is also gaining popularity because of the certificate-less mode of work. Blind signatures are appropriate schemes when user anonymity is wanted as property. One possible type of blind signature is ID-based blind signature based on bilinear pairings. For easy computation we look into pairing-friendly elliptic curves for implementation of pairings. This paper will review state of the art ID-based blind signature schemes from pairings over elliptic curves which are suitable for building blind signatures as part of e-voting protocols. We give comparative results about the computation cost of arithmetic operations. In our knowledge, this is first paper which gives head-to-head bandwidth comparison of the interactive protocol in the signing algorithm of blind signature schemes. The results are easy to use when choosing appropriate blind signature scheme for e-voting protocols.

The new tunable filter technology with truncated cone resonators is used here to realize multiple bands in different center frequencies in the same housing and with the same resonators. The bandwidth is varied from 20 MHz to 5 MHz and the center frequency is varied from 1930 MHz to 1990 MHz. The filter responses for 20 MHz and 5 MHz are achieved through complete external tuning and no cross couplings are applied. For the 15 MHz and 10 MHz responses the cross couplings are applied. The dielectric constant for the truncated cones and dielectric plugs is epsivr=35 and provides a very high Quality Factor Q and very good intrinsic spurious, which are so crucial for such a flexible design. To our knowledge this tunability in both bandwidth and frequency without affecting the Q is achieved for the first time. The design is patent-pending and we strongly believe that this represents a very important step towards the goal of remotely controlled filters for base stations.

The new tunable filter technology is used here to build full band (60 MHz) 9 pole dielectric resonator (DR) filters tuned at two different ranges separated by 200 MHz, PCS band (1930-1990 MHz) and UMTS band (2110-2170 MHz). All the measurements are taken in the same housing and the same resonators. The double conical resonators when put in proximity, provide the required strong couplings for the full band filter. The gap between the two conical parts that make the resonator, regulates the frequency over a very wide range without affecting the quality factor and helps provide a safe spurious free band. The fine tuning of the frequency is achieved with metal tuning plugs. Two different dielectric constants are used epsivr=35 and epsivr=45. In both cases, a typical 0.4 dB insertion loss is achievable for the 9 pole filter. An optimization of the design can push it very well near 0.3 dB for Er=35 or even lower. The design is patent pending and to our knowledge this full band DR filter tuned over such a wide range is presented for the first time.

We present here a new type of DR filters. The resonators have the shape of a truncated cone and their couplings are tuned by moving the resonators itself. Therefore, the layouts do not require the need of coupling screws and many of them do not even require the need of the irises. The unique shape makes the complete control of the strong couplings possible through the resonator movement. Using this technique we can build bandwidth tunable filters, i.e. different bandwidths in the same housing. Different measurements are presented with the same housing tuned from 1 MHz to 20 MHz. The technique also allows us to achieve up to 200 MHz bandwidth at 2 GHz, which is an order of magnitude greater than the present bandwidths that can commonly be achieved by standard DR filters. The new filters are simple in construction, with high Q and work particularly well at high dielectric constants. They can therefore be very small, compact and easily tunable. The unique layout intrinsically allows the implementation of the new cross-couplings. To our knowledge this is a breakthrough technology and all these are done for the first time.

We present here a breakthrough technology which is very promising for building broadband dielectric resonator (DR) filters. To the best of our knowledge this is the only technology versatile enough to allow us to build filters at different centre frequencies and the bandwidths ranging from 30MHz to 80MHz in the same housing (there are seven pending patents on this technology). Unlike the contemporary DR filter technology, this also allows to tune high dielectric constant resonators easily. The resonators have the shape of truncated cone. The way the filter is tuned and the particular shape of the resonators enhances the electromagnetic field energy in between the resonators by favoring the continuous components of the fields thus helping the tuning and rejecting the discontinuous components. As a result our technology can easily realize and control the strong couplings, which are usually difficult to be achieved with the existing DR technologies. The measurements for a 10 pole 60MHz DR filter at PCS bands without irises are presented. The insertion loss (IL) is 0.34dB. A tunable version of it is also presented. The particular shape of the resonator and the particular layouts improve the spurious response. The measured spurious response of the 60MHz filter is more than 700MHz, without a clean up filter. The incorporation of the comblines to further improve the spurious does not affect the tunability. Response of a 5 pole filter with three DR and two comblines are presented. The same housing is tuned externally for 25MHz, 20MHz and 15MHz and after fixing the bandwidth at 15MHz the center frequency is shifted by 70MHz. Many of the ideas to our knowledge are presented for the first time

In this paper, we demonstrate that basic implementation choices can have an order of magnitude of difference in the final power dissipation of the cutting-edge ASIC/SOC designs, and outline a basic checklist for power-aware implementation in deep sub-micron processes. We analyze the significant impact of 1) library choices, 2) register implementation, 3) tools utilization and 4) micro-architectural choices on dynamic power dissipation. We demonstrate that ASIC/SOC designers can achieve significant power reduction without resorting to full-custom techniques by following power-aware implementation prescriptions. We report eight-fold dynamic power reduction and five-fold clock power reduction on CMOS implementation of an adaptive processor IC in 0.13 /spl mu/m TSMC technology.

The authors present two different designs of integrated tuning elements for superconducting tunnel junction mixers. The structures consist of a self-complementary log-periodic antenna, superconductor-insulator-superconductor (SIS) tunnel junction, and a broadband superconducting tuning circuit placed between the center of the antenna and the SIS junction. The designs allow good coupling to relatively large-area (7 mu m/sup 2/) junctions. The best design has a 3-dB bandwidth of 102 GHz at the central frequency of 98 GHz, and 75 GHz at the central frequency of 492 GHz. Microwave scale-model measurements show excellent agreement with simulation results. Devices are being fabricated in niobium technology. >

A full 3D RLC extraction capability is presented which is suitable for very large nets on very large chips. The need, solution methodology, and usage in a real design environment are shown. The extracted parasitics and their effects on the delay/skew numbers are presented for real clock distribution circuits from real production designs, not test chips or special layouts.

Two-dimensional active grid arrays are being investigated for the submillimeter frequency range. The quasioptical Josephson oscillator is a large 2-D array of active antennas. Each active antenna consists of an active device integrated with a short antenna. For the active device, the Josephson function is used. Because of the extremely small power output of the single oscillator ( approximately nW), a large array of active antennas needs to be employed. The power radiated from each active antenna is quasioptically combined using the Fabry-Perot type cavity to give useful power levels. The arrays are designed for baseband operation, i.e. for the broad frequency range below the first array resonance. Several grid arrays have been measured and characterized. Of the four arrays considered, the slot array has the smallest input impedance and the dipole array has the highest. The bow-tie array represents the best combination of the wide baseband operating range and moderate driving point impedance. >