Portion Of Power Research Articles

Complete calibration of a six-port reflectometer with one sliding load and one short

A novel method is presented for calibrating a six-port reflectometer using only one sliding load of unknown reflection coefficient and one short as a calibration standard. The calibration procedure is derived from the fact that the Fourier coefficients of the periodic port power ratios corresponding to the sliding load positions are closely related to the six-port system parameters. The unknown reflection coefficient of the sliding load as well as the eleven system parameters at each frequency is determined in the procedure. The validity and utility of the proposed method are confirmed by experiments over the frequency range 8.5-12.0 GHz in 0.5 GHz steps with a rectangular waveguide sliding load and a polished metal standard short.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Single-wire GaAs IC communication technique

A novel method of single-wire chip-to-chip communication designed for DCFL based GaAs ICs using a three-level signal is described. Significant reductions in I/O port area and power consumption, and guaranteed data-framing synchronisation are the main advantages over previous two wire systems. Circuit diagrams and modified-SPICE simulations are presented.

Patient anesthesia and monitoring at a 1.5-T MRI installation.

This paper describes the facilities successfully used to provide patient monitoring and anesthesia support in a 1.5-T imaging installation. The requirements for the MRI site for anesthetic gases, shielded power, and radiofrequency ports are outlined. Specific modifications in anesthesia machines, anesthesia cart, laryngoscope, mercury sphygmomanometer, oximeter, and remote blood pressure devices are described. Additional aspects of patient monitoring and support, e.g., electrocardiogram and pressure infusion, are also discussed.

Thick Film Techniques for Microwave Integrated Circuits

A thick film approach to state-of-the-art microwave integrated circuits, which has been used to produce thousands of highly reliable low cost S-band and L-band solid state modules for production radar systems is described. These modules include low-noise amplifiers, double conversion mixers, interdigital filters, multiple port power dividers and switches, phase encoders, and power amplifiers. A discussion of the fabrication and microwave properties of thick film conductors, resistors, and capacitors is given along with photographs and performance data of various microwave integrated circuit modules that accumulated over a million device hours in operation without a failure.