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Satellite imagery and data collection have many advantages over other sources of soil observations. The developments in this field lead to the need of reducing cost with improving image construction methods. The concept of so-called satellite constellation accompanied by 3D vision technique may improve the coverage of a specific area. Here presented a satellite constellation conception is for a 3D reconstruction of urban areas, filling the gap of the required temporal resolution to properly monitor this contribution. Thus, a miniaturization method of space vehicles was proposed using CubeSat constellation resides at an altitude of 500 km. The number of satellites required to meet the challenges of earth observation is nine satellites. To accomplish the main goal, meeting the adequate resolution, a development study around a deployable optic camera is presented for a 3D reconstruction.

ABSTRACTMany people in developing countries are required to travel for several hours to see a doctor. The concept of so called telemedicine accompanied with developments in the field of wireless communications may improve the health care. Here presented telemedicine system is for a distance consultation. It is based on a pocket smartphone using its camera to develop a video broadcasting mission for a real-time consultation. However, developing countries in the Middle East and North Africa suffer network coverage in most areas. To overcome this issue, the system includes a software defined radio in order to integrate the small satellite technology in the telemedicine routine. The proposed pico-satellite constellation can provide an interesting solution for near real-time transmission, which will significantly improve the health care in remote areas.

In this paper, an optimization technique for active inductor circuit forward noise, size area, and power dissipation is proposed through careful selection of the number of gate fingers Nfof a nanoscale MOS transistor. According to simulation results, the application of supply voltage scaling and multi-gate finger transistor techniques can therefore introduce simultaneously a reduction in power consumption around 60% (from 3.35 to 1.32 mW) and a minimization in noise performance at 2 GHz from 3.15 to 2.1 ɳV/√Hz with a small size area and wide tuning range.

Localisation methods based on the received signal strength indicator (RSSI) are widely used in wireless sensor networks (WSNs). They offer an energy reduced and cost-effective solutions for wireless localisation. Due to radio irregularity, RSSI localisation is vulnerable to multipath, shadowing, interference and environmental effects, which reduces the accuracy of localisation results. In this paper, a new distance measurement correction algorithm is presented, which is based on feedback filter and hardware characteristic. It implements the feedback filter with consideration of historical values of RSSI. This enables to predict possible values of RSSI and thus nodes positions. Hardware characteristics, such as multiplication and summation capabilities are explored to improve the localisation accuracy. Real experiments were carried out on panStamp sensor nodes at two different temperatures. The new proposed RSSI technique shows a reduced localisation error compared to the simple RSSI method.

Active inductors circuits are developed as an alternative solution for multiband systems. In this context, this paper presents a wide tunability, a low power, high-Q differential active inductor (DAI) using 0.13 μm CMOS technology. This work proposes a DAI using two cascode-grounded active inductors and cross-coupled negative resistance to decrease the noise and to improve the quality factor. The inductance tuning range, quality factor, and other performance are improved by using a technique enabling to vary the current crossing the proposed circuit and by inserting a tunable feedback resistance. Results based on post-layout simulations (PLS) illustrate that the inductance tuning range from 79.8 to 495 nH resulting in a frequency tuning range from 3.19 to 0.784 GHz. An excellent tunable quality factor almost of 2600 is achieved at 1.47 GHz. The core DAI dissipates between 1.57 and 2.59 mW on a 1 V supply voltage. The circuit has an input 1 dB compression point Pin, 1 dB of −2.32 dBm. Simulated noise at 0.784 GHz is less than 3.48 nV/√Hz. The chip area of the DAI with testing pads is around 0.002 mm2.

ABSTRACTThis paper presents a new topology for realizing a single-ended inductor employing a minimum number of passive components. The active inductor achieves a high quality factor of 895 over a frequency range of 1700 MHz. Its self-resonance frequency is 5.5 GHz. The achieved range of sweep for inductance (L) varies from 3.55 to 26 nH. The circuit draws 0.5 mA current from 1.0-V supply and occupies an effective active area of 22 × 27.5 µm2, while the noise voltage is less than . The proposed inductor is designed and simulated in a 90-nm TSMC MS/RF CMOS process.

A novel experimental set-up is developed and validated to characterize high voltage diodes in transient switching mode. Parameters extracted from DMTVCA and OCVD techniques, like ambipolar lifetime, epilayer thickness and doping level, diode area, are validated in a buck converter with resistive load. The experimental set-up allows to measure the current and voltage transient characteristics without noise and influence of high parasitic wiring. Experimental results are compared with device simulations and a good correlation is found.