This paper presents a 1-W, class-E power amplifier that is implemented in a 0.35-/spl mu/m CMOS technology and suitable for operations up to 2 GHz. The concept of mode locking is used in the design, in which the amplifier acts as an oscillator whose output is forced to run at the input frequency. A compact off-chip microstrip balun is also proposed for output differential-to-single-ended conversion. At 2-V supply and at 1.98 GHz, the power amplifier achieves 48% power-added efficiency (41% combined with the balun).

A 1.9-GHz, 1-W CMOS class-E power amplifier for wireless communications

A simple method using lumped inductors to compensate unequal even- and odd-mode phase velocities in parallel coupled microstrip lines is presented. The singly and doubly compensated cases are analyzed to enable the optimum inductor values and the electrical lengths of the compensated coupled lines to be calculated from closed-form expressions. The technique proposed not only improves the performance, but also yields a more compact design. To demonstrate the technique's broad range of applicability, the compensated coupled-line structure is used to enhance the performance of a 900-MHz Lange coupler, a 1-GHz multisection 10-dB coupler, a 900-MHz planar Marchand balun, and a 1.8-GHz parallel coupled bandpass filter

Inductively Compensated Parallel Coupled Microstrip Lines and Their Applications

A simple and successful method for miniaturizing a ring coupler is proposed. The size of the ring coupler is reduced by connecting multiple open stubs on the inside of the ring. There is no need of any lumped element, via hole or wire bond, but only microstrip lines. The reduced size is arbitrary and the results of the miniaturized ring coupler coincide with that of the traditional one.

Miniaturized ring coupler of arbitrary reduced size

The heat-shock protein 27 (HSP27) is up-regulated in tumor cells and released in their microenvironment. Here, we show that extracellular HSP27 has a proangiogenic effect evidenced on chick chorioallantoic membrane. To explore this effect, we test the recombinant human protein (rhHSP27) at physiopathological doses (0.1–10 μg/ml) onto human microvascular endothelial cells (HMECs) grown as monolayers or spheroids. When added onto HMECs, rhHSP27 dose-dependently accelerates cell migration (with a peak at 5 μg/ml) and favors spheroid sprouting within 12–24 h. rhHSP27 increases VEGF gene transcription and promotes secretion of VEGF-activating VEGF receptor type 2. Increased VEGF transcription is related to NF-κB activation in 30 min. All of these effects are initiated by rhHSP27 interaction with Toll-like receptor 3 (TLR3). Such an interaction can be detected by immunoprecipitation but does not seem to be direct, as we failed to detect an interaction between rhHSP27 and monomeric TLR3 by SPR analysis. rhHSP27 ...

https://faseb.onlinelibrary.wiley.com/doi/pdf/10.1096/fj.12-226977

Extracellular HSP27 mediates angiogenesis through Toll-like receptor 3

A 2-D contour integral-equation method for the frequency-domain analysis of arbitrarily shaped power bus structures is presented. The numerically efficient approach allows the rapid and accurate computation of the frequency-dependent transfer parameters between an arbitrary number of ports, as required for embedding the power plane structure into network simulation. A formulation is developed for calculating the voltage distribution between the planes, as well as for determining the resulting radiated fields based on the field-equivalence principle. The method is applied for several test boards including a populated board with a surface-mount decoupling-capacitor network. The suggested approach is well confirmed by an analytical solution for the rectangular structure, by measurement and 3-D full-wave simulation results.

Efficient 2-D Integral Equation Approach for the Analysis of Power Bus Structures With Arbitrary Shape

Transmission line theory two-port parameters microstrip transmission lines - basic theory microstrip transmission lines - further considerations discontinuities the Smith chart and its uses hybrid-line couplers parallel-coupled lines and directional couplers filters miscellaneous components active circuit characterization microstrip circuits and subsystems microstrip experiments.

E. H. Fooks

Papers

Microwave Engineering Using Microstrip Circuits