Simultaneous Transmission of Tomography Transceivers Using Multiple M-Sequence Signals

Abstract

We investigated the effect of process damage induced after capacitor etching procedures in the process of ferroelectric random access memory (FeRAM) fabrication for SrBi 2 Ta 2 O 9 capacitors. We found that this damage was suppressed by postmetallization annealing (400 C, 30 min in O 2 ) and that imprint characteristics were improved by the annealing, because active elements such as hydrogen and water induced during contact hole formation on tungsten plugs and first-metal formation are adsorbed effectively by the annealing before they penetrate into these capacitors.

Position detection of small objects in indoor environments using coded acoustic signal

“…This signal is often used in the field of communication, measurement and system control. In an underwater acoustic measurement, it has been applied to ocean acoustic tomography [9,10].…”

Introduction of measurement techniques in ultrasonic electronics: Basic principles and recent trends

“…When ultrasound reaches the seabed, scattering and absorption occur, whose profile depends on the roughness and type of material. Hence, the measurement of ultrasound propagation is useful for predicting underwater profiles, such as temperatures, currents, tidal effects, [449][450][451][452][453][454][455][456][457][458][459][460][461][462][463][464][465][466][467][468] and underwater structures. [469][470][471][472] Such measurement has been conducted over large regions of the ocean (e.g., on the order of 100 km).…”

Real-time monitoring system of vortex wind field using coded acoustic wave signals between parallel array elements

“…[12][13][14][15][16][17][18][19] Large-scale application of the technique has been limited to the ocean. [20][21][22] To solve the problems, an acoustic travel-time tomography system for the monitoring of the vortex wind flow velocity profile has been developed, where multichannel parallel acoustic transmitter/receiver pairs are placed along opposite sides of the monitoring region. [23][24][25] For the simultaneous transmission and reception of the multichannel signals, coded modulation was incorporated in order to realize the real-time observation that keeps up with the rapid change of wind field.…”