One of the problems in Computer Vision is recovery of object shapes from noisy images. Associated with this problem is the question of what is a shape and how is it to be represented. Since answers to these questions have to be ultimately tailored to the uses one has in mind, one has to bring into consideration potential applications and with it, the question of practical algorithms for impleme...

A wideband CMOS variable gain low noise amplifier suitable for multi-standard radio applications between 75 MHz and 3 GHz is presented. Wideband matching to 50 Ohm (single ended) is achieved using a common-drain feedback stage whereas variable gain is realized using a resistive attenuator. The circuit has been designed in a 65 nm CMOS process and achieves 22 dB maximum gain, 29 dB gain range, 3...

In this paper, a low-power ultrawideband (UWB) lownoise amplifier (LNA) is proposed. Here, we propose a structure to combine the common gate with band pass filters, which can reduce parasitic capacitance of the transistor and to achieve input wideband matching. The π-section LC network technique is employed in the LNA to achieve sufficient flat gain. A bias resistor of large value is placed bet...

We present a new steady-state frequency-domain model of highly nondegenerate four-wave mixing in bulk semiconductor optical amplifiers (SOA’s). The model can handle a large number of interacting optical fields and situations in which the nonlinear interactions are complex. It accounts for the longitudinal dependence of the population inversion in the SOA and the spectral dependence of the gain....

A fully integrated CMOS wideband Low Noise Amplifier (LNA) operating over 2.3–7 GHz is designed and fabricated using a 0.18 μm CMOS process. The proposed structure is a common sourcecommon source (CS-CS) cascode amplifier with a coupling capacitor. It realizes both low voltage drop at load resistor (Rload) and high gain over 2.3–7 GHz with simultaneous noise and input matching and low power con...

This paper presents the analysis, design and implementation of a millimeter-wave W-band power detector. Fabricated in a 0.18-μm SiGe BiCMOS technology, the detector circuit exhibits a responsivity of 91 kV/W, a noise equivalent power of 0.5 pW/Hz, and a noise figure of 29 dB. The power dissipation of the detector is 75 μW. Reasonable agreement between simulations and measurements is obtained. T...