Hitachi-kokusai Electric Inc.

Nikon Corporation

Sony Corporation

Ricoh Company, Ltd.

Kokusai Denki Electric Inc.

Kei Ito

Tatsuhiro Nakada

Masafumi Mimura

Daiki Hoshi

Hiroshi Hayashi

Hiroki Kato

Yasushi Fukuda

Keisuke Yamamoto

Mitsuharu Ohki

Tomoo Mitsunaga

Kazumasa Ito

Hideki Sasaki

Yuji Yamaguchi

Kenji Shiraishi

Hidetoshi Nagano

Hajime Hosaka

Masatoshi Imai

Naosuke Asari

Satoru Ejima

Kazuhiro Yano

Toshiharu Noda

Sumito Arakawa

The present invention allows a gain control to be appropriately effected even when a frame including no preamble signal block is used for wireless communications. The following processes are effected in a transmission power control unitof a transmission unit. Specifically, an automatic transmission gain control unitmultiplies a transmission signal by a gain value that is the difference between the power of a signal loop-backed from a power amplifierand the power of the transmission signal. A fixed transmission gain multiplying unitmultiplies the transmission signal by a predetermined gain value or by the gain value used in the automatic transmission gain control unitduring the preceding frame. A selection unitselects the transmission signal as gain-controlled by the automatic transmission gain control unitin a case of a preamble signal block being included in the frame of the transmission signal and selects the transmission signal as gain-controlled by the fixed transmission gain multiplying unitin a case of no preamble signal block being included in the frame of the transmission signal.

Wireless communication system, transmission method and reception method

A wireless communication device includes frequency hopping means for changing a radio frequency based on a temporarily defined pattern, and a frequency offset compensation unit. The frequency offset compensation unit includes a frequency offset calculator that calculates a frequency offset amount from a received signal, a hopping frequency value converter that uses the frequency offset amount, a radio frequency from which the frequency offset amount is calculated, and a transition destination radio frequency transitioned by the frequency hopping means to calculate an estimated frequency offset value for the transition destination radio frequency, and a rotator that uses the estimated frequency offset value for the transition destination radio frequency to perform phase rotation on the received signal.

Wireless communication device and frequency offset compensation method for wireless communication device

A reception device including reception antennas is provided. In the reception device, a demodulation unit is configured to calculate, for each of a plurality of antenna combinations of the reception antennas, log likelihood ratios of coded bits of error correction code obtained from reception signals of the reception antennas. A mutual information amount calculation unit is configured to calculate an average mutual information amount based on the log likelihood ratios corresponding to each of the antenna combinations. An antenna combination selection unit is configured to output determination information for specifying one of the antenna combinations for which the average mutual information amount is the maximum. A signal selection unit is configured to select the log likelihood ratios corresponding to the specified antenna combination based on the determination information, and a decoding unit is configured to decodes the selected log likelihood ratios.

Reception device and wireless communication system

A wireless communication device suppresses increase in computation scale when applying maximum likelihood detection to a multi-level modulation scheme. Units calculate a likelihood, bit log-likelihood ratio, and mutual information content for the separation result of a received signal on the basis of the signal point of a reference selected from among a plurality of signal points that a transmitted signal can assume. A transmission candidate point selection unit selects signal points in a number that corresponds to the mutual information content as transmission candidate points from among the plurality of signal points in ascending order of distance to 0 and distance to 1 for each modulation bit that constitutes the signal point of the reference. A reception candidate point that is a candidate for the received signal is calculated. An external LLR calculation unit calculates the bit log-likelihood ratio by an MLD method.

Wireless communication device and wireless communication method

A peak power reduction device includes a unit for dividing digital information to be transmitted into a plurality of streams; a unit for selecting the modulation level of the streams and distribution of transmission power according to a transmission state; a unit for performing singular-value decomposition on the transmission path characteristic of a streams and precoding the resultant data by a right singular value matrix; a unit for performing complex mapping on the subcarrier of a stream according to the modulation level; a unit for converting a complex mapping signal into a time domain signal; a first unit for storing a conversion result as a time domain signal; a second unit for calculating a peak time signal exceeding a predetermined threshold value from a peak value, if any exists, that exceeds a prescribed threshold value for the amplitude of the time domain signal.

Peak power reduction device in communication system

SISO decoding of a reception signal having a scrambled symbol arrangement is realized using a process having reduced complexity. Coordinates are generated for a reference point obtained by scrambling and mapping a symbol number not a symbol reference point position. This reference point simulates transmission-side scrambling and is generated for each symbol number by a first mapping unit. Because the binary expression of a corresponding original signal number is retained, a bit likelihood calculation unit can easily calculate a bit likelihood based on the distance between the reference point and a reception signal. The calculated bit likelihood is then deinterleaved and subjected to SISO error-correcting decoding. The thus obtained bit likelihood is then reinterleaved and used to calculate a symbol probability. Soft symbols are generated through the multiplication of all the calculated symbol probabilities by corresponding reference points output by a second mapping unit similar to the first mapping unit.

Wireless communication device and method

Disclosed is a reception apparatus that has solved a problem that fluctuations cannot be followed immediately after a commencement of turbo equalization in a high-speed fading environment. A reception apparatus includes a soft interference canceller, an MMSE equalizer, a likelihood calculator, a de-interleaver, an SISO decoder, an information bit hard decision unit, a subtracter, an interleaver, a soft estimation value calculator, a zero storage unit, a known signal memory unit, a transmission path estimator, and a plurality of switches. At the time of equalization, the transmission path estimator uses, as a reference signal, a known signal stored in the known signal memory unit or an output of the MMSE equalizer. Meanwhile, at the time of a first equalization, the soft interference canceller is given a '0' value from the zero storage unit as a reference signal.

Reception apparatus performing turbo equalizations

An object of the present invention is to generate a soft estimation value where missing of bit information is avoided and to implement turbo equalization processing in a wireless transmission apparatus and a wireless transmission system where termination processing is not performed in an error correction coding part and interleave processing over frames is performed. A wireless transmission system of the present invention includes a transmission apparatus and a reception apparatus. The transmission apparatus includes an error correction coding unit, a first interleave unit, a second interleave unit, and a digital modulation unit. The reception apparatus includes a unit that detects a reception signal, a demapper unit, a second deinterleave unit, a unit to store a received bit logarithm of likelihood ratio in a frame buffer, a frequency interleaver data extraction part that extracts data of a predetermined period, a decoding part, and a hard decision part.

Wireless transmission system and reception device

When a channel between a transmission apparatus and a reception apparatus is distorted by multipath fading or other reasons, linear interpolation between pilot subcarriers produces a large estimation error, resulting in an increase in an equalization error and a decrease in reception performance. The present invention allows feedback of a signal that undergoes error correction, reduction in the channel estimation error through repeated channel estimation, and improvement in the reception performance.

Reception apparatus

An image-processing program for cell observation comprises obtaining a first image showing a plurality of cells in an observation region, the first image being captured by an imaging device, and a second image showing the observation region, the second image being captured by the imaging device a predetermined time before the first image is captured; selecting one cell as a cell of interest from the plurality of cells included in the first image; specifying cells on the periphery of the cell of interest as peripheral cells; calculating movement statistics of the peripheral cells with respect to the cell of interest on the basis of the amount of relative movement of the cell of interest and the peripheral cells in the first image and the second image; and outputting the calculated movement statistics of the peripheral cells.

Image analysis method for cell observation, image-processing program, and image-processing device

An image processing device determines the degree of activity of a cell during cell viewing. An imaging device captures first and second images of a cell under observation. After aligning the rotational angle orientations on the image plane of the cell under observation that is included in the images, a correlation value or difference of intracellular texture feature values in the first image and second image, is sequentially computed. A time series variation of the computed correlation value or difference is then derived, and the degree of activity of the cell under observation is detected based on the state of variation.

Method for detecting cell states, and image processing device for cell viewing

An image processing program (GP) attains (S) time lapse images, extracts (S) a cell aggregation from each of the obtained images, and calculates (S), for the entire region of the cell aggregation, the spatial distribution in pixel values and temporal change in pixel values of a small region in the extracted cell aggregation. The program determines (S) the state of change of the cell aggregation toward becoming multi-layered, on the basis of the calculated spatial distribution and time lapse change of pixel values, and outputs (S) the results of the determination. The image processing program (GP) is configured so as to determine and output, from time lapse images, the state of change of the cell aggregation toward becoming multi-layered.

Technique for determining the state of a cell aggregation image processing program and image processing device using the technique, and method for producing a cell aggregation

An image-processing method for processing a time lapse image includes acquiring a first image obtained by capturing an image of an object located within a field of view using an imaging device and a second image obtained by capturing an image of the object located within the field of view using the imaging device after a predetermined time period has elapsed, calculating a positional correction value for a positional shift between the first image and the second image, by using a correlation function weighted according to an image feature of each of the objects included in the first image and the second image, and performing, based on the calculated positional correction value, a positional correction between the first image and the second image. The time lapse image is generated using the first image and the second image on which the positional correction has been performed.

Image-processing method, image-processing program and image-processing device for processing time-lapse image

An image processing program for cell observation in which living cells can be distinguished from foreign matter other than living cells during cell observation under wide observation conditions. The image processing program includes a step for capturing first and second images of an object positioned in the observation field of view at a predetermined time interval, a step for extracting a representation of the object shown in the obtained images, steps for aligning the rotational angular orientation of the object in the image plane and computing a correlation value, a step for determining whether the object is a living cell on the basis of the computed correlation value, and steps for outputting the result of the decision made with regard to the object.

Method for distinguishing living cells during cell observation, image processing program for cell observation, and image processing device

An integrated device includes at least one data processing device and at least one memory macro accessible by the data processing device. The data processing device and the memory macro are laid out so that a memory address and a power consumption have a correlation.

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Tokyo, Japan

Kei Ito