Oki Electric Industry Co., Ltd.

Kiyohito Tokuda

Satoru Shimizu

Atsushi Fukasawa

Yumi Takizawa

Eiichiro Kawakami

Manabu Kawabe

Takuro Sato

Toshio Kato

Atsuhiko Sugitani

A code division multiple access receiver estimates symbol values transmitted by different stations by despreading a combined received signal, weights the estimated symbol values by use of weighting factors calculated for the different stations, respreads the weighted symbol values to estimate the interference due to each station, and subtracts the estimated interference from the received signal to produce a residual signal. The weighting factors can be calculated from the residual signal; the weighting factors are calculated so as to minimize the power of the residual signal. The weighting factors are adjusted at certain intervals, preferably at intervals determined from the rate of fading of the received signal.

CDMA receiver with weighted interference cancellation

The signal transmission equipment is comprised such that a signal point does not cross the origin of the constellation by selecting signals to be input to the QPSK modulator, and the positions of the signal points in the constellation.

Signal transmission equipment

Features are extracted from a sampled input signal by performing first linear predictive analyses of different first orders p on the sample values and performing second linear predictive analyses of different second orders q on the residuals of the first analyses. An optimum first order p is selected using information entropy values representing the information content of the residuals of the second linear predictive analyses. One or more optimum second orders q are selected on the basis of changes in these information entropy values. The optimum first and second orders are output as features. Further linear predictive analyses can be carried out to obtain higher-order features. Useful features are obtained even for nonstationary input signals.

Multi-stage linear predictive analysis method for feature extraction

A three-dimensional image generator generates a random signal which it filters in two dimensions generate a realistic three-dimensional image of a natural object such as ocean waves or clouds. By performing the filtering operation repeatedly on overlapping intervals of the random signal, related images can be obtained to generate moving scenes at real-time rates. Two or more partial image generators can be connected in parallel to generate different directions of motion, or different parts of a complex scene. Within each partial image generator, two or more space filters can be connected in parallel to generate superimposed patterns, such as small ripples superimposed on large waves. This image generator is much faster than previous, fractal image generators.

Three-dimensional image generator

Features are extracted from a sample input signal by performing first linear predictive analyses of different first orders p on the sample values and performing second linear predictive analyses of different second orders q on the residuals of the first analyses. An optimum first order p is selected using information entropy values representing the information content of the residuals of the second linear predictive analyses. One or more optimum second orders q are selected on the basis of changes in these information entropy values. The optimum first and second orders are output as features. Further linear predictive analyses can be carried out to obtain higher-order features. Useful features are obtained even for nonstationary input signals.

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Tokyo, Japan

Kiyohito Tokuda