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The main task of the RFBR_BRICS project 'Superconducting terahertz receivers for space and ground radio astronomy' is the development of terahertz technologies and the creation of superconductor-insulator-superconductor (SIS) receivers with quantum sensitivity for novel radio telescopes, including ultra-long baseline radio interferometers. This research program brings together scientific groups from four BRICS countries (Brazil, Russia, China and South Africa), which have a high international reputation and successful experience in the development of ultrasensitive receivers. The report discusses the working plan and the first results of the project; in particular development of the SIS-receivers for Russian space program 'Millimetron'

Tl 2 Ba 2 CaCu 2 O 8 is layered cuprate superconductor with high anisotropy. Using Tl 2 Ba 2 CaCu 2 O 8 film and asymmetric resonator structure, we designed and fabricated a kind of terahertz metamaterials. The tuning of the Fano-type resonance with the change of temperature is experimentally demonstrated.

Mechanical oscillators can be implemented to store and/or transfer information. In order to couple a mechanical oscillator to a superconducting qubit, we fabricate a superconducting capacitor using the diluted photoresist or electron beam photoresist as a sacrificial layer. The upper plate of the capacitor, a suspended membrane, acts as a mechanical oscillator. We obtain its mechanical resonant frequency and response to the input microwave. Such mechanical oscillator can be used as the capacitor of a superconducting qubit to form a coupled system. Another way to transfer information between a mechanical oscillator and a superconducting qubit is to take advantage of a superconducting microwave resonator such as a coplanar waveguide resonator. In order to control the resonant frequency of the resonators, we introduce a DC voltage bias between the upper and lower plates of the capacitor. We demonstrate the dependence of the resonant frequency on the applied DC voltage.

The properties of terahertz (THz) power detectors based on Superconducting NbN hot electron bolometer (HEB) with microwave (MW) readout are reported here. Features of relaxation oscillations probed with MW when the HEB is not pumped, pumped by THz source or heated by raising the bath temperature are studies. The periodic pulse in the reflected MW signals both in time and frequency domains show that the relaxation oscillation frequency increases with the bias voltage, incident THz power and/or bath temperature. The frequency count forms a quadratic polynomial fit to the bias voltage, a linear fit to the incident THz power and an exponential fit to the bath temperature. Based on the above results, incident THz power between 8–90 nW is measured using the HEB.

Design patterns are a set of solutions in software development process, and have been successfully applied to the modern software development process, greatly improved the performance of the software systems, such as reusability, reliability, flexibility and scalability. The paper analysis the radar signal processing system and combines it with the design patterns, and divide the system into processing component, interaction component and communication component, and choose three kinds of patterns builder pattern, state pattern and single pattern to design and implement the radar signal processing system. By combination with the design patterns, it could improve the scalability, universality and reusability of the system and the designed signal processing system can be used in variety of radars.

Electromagnetic environment prediction refers to forecast the developing trend of electromagnetic environment in future based on forecast model. Through the research on the constitute and the dynamic characteristics of electromagnetic environment, according to electromagnetic environment simulation process and external interference electromagnetic environment, mutual interference, dynamic characteristics of the electromagnetic environment faced by electronic information equipment, external interference model, the internal mutual interference model and the dynamic control model of electromagnetic environment are established. At last, according to the electromagnetic environment simulation and prediction, multi point receiving simulation method are put forward and the simulation process is established, which provide support for electromagnetic environment prediction research. Comparison of simulation and outdoor experiments show that the prediction models and methods described herein improve the efficiency and accuracy of prediction of the electromagnetic environment.

Recently, the real-time synthetic aperture radar (SAR) imaging technique is a hotspot of research in the field of remote sensing and military applications. As the SAR imaging algorithm is associated with high data and computation intensive, it is suitable for using hybrid storage systems, e.g. A cluster, for the performance acceleration. To design a SAR algorithm with high performance, we need consider a prerequisite to maximize the parallelizability of the algorithm due to multi-level parallelization features of the cluster platform. Focusing on the large-scale data, we explore concurrency characteristics of the SAR imaging algorithm on a hybrid storage system, and propose some parallel optimization techniques to accelerate the SAR imaging algorithm. According to the study, we implement a parallel SAR imaging algorithm and evaluate its performance. Experiment results show that the optimized SAR imaging program has high-speed network utilization, and can realize obvious improvement on the performance.

We propose a novel kind of terahertz radiation source utilizing grapheme surface plasmon polaritons (GSPPs) excited by parallel moving electron beam. Theoretical analyses show that terahertz radiation can generate from graphene sheet on a periodic grating structure. The intensity of the radiation are greatly enhanced due to GSPPs and the frequency of the radiation can be widely tuned by both of the electron beam energy and chemical potential of graphene. The experiment based on this mechanism are in progress.

Being frequency tunable sources, Josephson junctions are attractive for the generation of high frequency electromagnetic radiation. Recently, coherent off-chip THz radiation with an extrapolated output power of some μW was observed. Different mechanisms, like geometry resonance and heating effect, have been raised to explain how the junctions in the stack are synchronized, while there is no consensus which has been reached. To get further understanding on this issue, it is expected to demonstrate the process that the electromagnetic field and thermal distribution evolve as the detected terahertz(THz) emission signal varies in experiment. To realize this goal, we developed a home-made system, by combining a low-temperature scanning laser microscope (LTSLM) and a THz interferometer. With this setup, we are able to simultaneously detect THz emission and observe LTSLM images. In this talk, we will report the unambiguous observation of the correlation between the standing wave patterns, the hotspot formation and the THz radiation characteristics of the Bi2Sr2CaCu2O8 (BSCCO) junctions stack with a mesa structure. We stress that this joint measurement setup will play an important role in studying solid state microwave or terahertz devices.

In order to reduce the encoding complexity and improve the random access performance of Joint Multi-view video coding (JMVC), this paper proposed a fast mode selection algorithm based on texture segmentation and a new prediction structure. In the fast mode decision algorithm, macroblocks are classified according to their texture complexity, and each frame is divided into flat background region, complex background region and foreground region by an adaptive threshold. Different segmentation methods are used in different regions to reduce the candidates for mode decision. Predictive modes are filtered further according to the texture direction of macroblocks, which can eliminate some unnecessary modes and improve the speed of mode searching. In the proposed prediction structure, the selection of I-view is adjusted and some inter-view prediction is removed. Compared with JMVC, experimental results show that the proposed algorithms can improve random access performance and reduce up to 65% of the computational time, while maintain high RD performance.

We report on THz emission measurements and low temperature scanning laser imaging of Bi 2 Sr 2 CaCu 2 O 8 intrinsic Josephson junction stacks. Coherent emission is observed at large dc input power, where a hot spot and a standing wave, formed in the “cold” part of the stack, coexist. By changing bias current and bath temperature the emission frequency can be varied over a wide range of 350–780 GHz; the variation matches the well-known Josephson-frequency relation. The linewidth of radiation, recently measured with an integrated superconductor-insulator-superconductor (SIS) receiver, is as narrow as 6 MHz, much smaller than expected from a purely cavity-induced synchronization. Thus, an additional mechanism seems to play a role. Some scenarios, related to the presence of the hot spot, are discussed.

As to the problem of great complexity of traditional adaptive window matching algorithm, a simple adaptive window matching algorithm is proposed in this paper, which use various square or rectangular windows of different size based on the different gradient of points to be matched. Moreover, for better matching effect, a regional seed propagation method is proposed based on the disparity smoothness constraints and the assumption that adjacent pixels of similar color should have the same disparity. Experiments show that compared with traditional adaptive window matching algorithms, the computation complexity has been decreased significantly and the matching accuracy rate has been improved effectively.

30th URSI General Assembly and Scientific Symposium, URSIGASS 2011; Istanbul; Turkey; 13 August 2011 through 20 August 201, Rectangular Bi2Sr2CaCu2O 8+δ (Bi2212) mesa structures were fabricated on as-grown Bi2212 single crystal superconductors using standard photolithography and Ar ion beam etching techniques. We have performed c-axis resistance versus temperature (R-T), current-voltage (I-V) characteristics and bolometer measurements. Furthermore, in contrast to previous studies, the emission frequency was determined using interferometer set up instead of FTIR. The interference patterns were detected outside the cryostat after traveling long way through ambient space. The emission frequency calculated by Fourier transform of interference data is consistent with Josephson frequency-voltage relation. © 2011 IEEE., Scientific and Technical Council of Turkey project no. 110T248

With the development of computer vision technology, stereo video technology gets more and more popular. However, compared with the growing number of stereoscopic display devices, the 3D content for display is obviously insufficient. On the other hand, there exists tremendous amount of 2D video resources. As a result, the 2D to 3D video conversion becomes a common interest of both academic and industrial communities. This paper focuses on the characteristics of 2D to 3D technology, summarizes different transformation methods, and presents a semi-automatic depth extraction scheme from motion estimation. The experimental results show that this scheme can obtain 3D depth maps with relatively high quality.

We designed a useful digital signal generating system which transforms various file data stored in SD card into SDI output signal based on the FPGA hardware platform. This paper presents the hardware design and implementation of the system, which includes two steps. First step is the design of the NIOS II system, which includes SRAM controller and SD card controller IP core design. Second step is the generation of the whole functional SOPC system which using Quartus II development tool. NIOS II system is integrated with the scrambling encoders in this step. And then the hardware system is implemented.