Fujitsu Corporation

Mobile Tech, Inc.

Yasuharu Amezawa

Takanori Iwamatsu

Shinichi Sato

Kazuo Nagatani

Hiroyoshi Ishikawa

Makoto Yoshida

Kazuyuki Ozaki

Hikaru Ishikawa

Ryo Koizumi

Takeshi Sugiyama

Masanori Yofune

Masayuki Suto

Masayuki Sutoh

Takuro Nishikawa

A wireless communication device includes a processor. The processor estimates a quality of a received signal that is transmitted from a source device. The processor determines a communication parameter for a next communication transaction based on an evaluation value that indicates a result of subtracting a second value from a first value, the first value being determined based on a coding rate and a data length of a data signal received from the source device, the second value being determined based on the data length, a modulation scheme and a quality of the data signal. The processor reports the communication parameter to the source device.

Wireless communication device and communication parameter report method

A peak suppression device includes a suppression-signal generating unit and a band pass filter (BPF). The suppression-signal generating unit generates a suppression signal that is obtained by adding, to a transmission signal, a frequency component in which components of frequencies from a boundary of a band of the transmission signal to a frequency that is away therefrom toward an out-band of the transmission signal by predetermined frequencies are attenuated, out of frequency components of a signal to suppress a peak of the transmission signal. The BPF attenuates, after the suppression signal is amplified by the amplifier, a frequency component outside the band of the transmission signal in the amplified suppression signal.

Peak suppression device and peak suppression method

An object of the present invention is to provide the compression device and the expansion device of a complex digital signal, which further raise the compression ratio of the compression digital signal. The compression device of the present invention comprises: first section that acquires a first phase and a second phase, wherein with a complex digital signal being inputted into the complex digital signal compression device, the first phase is a phase, in polar coordinates, which the complex digital signal has, and it is assumed that the complex digital signal inputted into the complex digital signal compression device is expressed as a sum of two complex digital signals with an equal amplitude, phases of which are centered at the first phase and are shifted by a phase that equals to the second phase in the positive and negative direction respectively; and second section that compresses the first phase and the second phase respectively by performing quantization. The expansion device of the present invention comprises third section and fourth section which perform the inverse processing of the second section and the first section, respectively, mentioned above.

Complex digital signal compression device, method and computer-readable storage medium, complex digital signal expansion device, method and computer-readable storage medium, and communication device

An apparatus includes a selection unit that selects an estimation target path to be used to estimate a propagation channel estimation value, among a plurality of paths based on a characteristic value of each path; a determination unit that determines an estimated reception time at which a signal as a target of estimation of the propagation channel estimation value among signals propagating through the estimation target path is received; an estimation unit that estimates an amplitude and a phase of the signal propagating through the estimation target path at the estimated reception time as a propagation channel estimation value of the estimation target path; and a processing unit that performs an interpolation/extrapolation process using the propagation channel estimation value of the estimation target path to estimate the propagation channel estimation value at a time other than the estimated reception time of the signal propagating through the estimation target path.

Propagation channel estimation apparatus, receiver, and propagation channel estimation method

An apparatus for estimating phase/amplitude characteristics of a propagation path. The apparatus removes, from a receive signal on a data channel on which known information is transmitted upon being time-multiplexed between items of unknown information, transmit information on this channel, which provides phase/amplitude information indicative of phase/amplitude characteristics that this data channel has suffered over the propagation path. The apparatus further removes from a receive signal on a data channel on which only unknown information is transmitted, transmit information on this channel, which provides phase/amplitude information indicative of phase/amplitude characteristics that this data channel has suffered over the propagation path. The apparatus includes an adder for adding the two phase/amplitude information and an estimation unit for estimating, from an adder output, a phase characteristic and an amplitude characteristic that each channel has suffered over the propagation path.

Apparatus for estimating propagation path characteristics

In a mobile communication receiving apparatus in which signals received on a plurality of receiving paths (branches) are combined by a combiner, correlation between noise signals contained in the signals received on respective ones of the branches is detected by a noise correlation calculating unit, and control is exercised so as to maximize signal-to-noise power ratio of the combined signal based upon the correlation calculated in the noise correlation calculating unit. Signal-to-noise power ratio can be maximized even if noise components contained in respective ones of the branch signals are mutually correlated.

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Kawasaki, Japan

Yasuharu Amezawa