Abstract: A receiving device includes: a propagation path compensation unit that compensates a signal by using a propagation path characteristic; a power arithmetic section that arithmetically operates power of a signal; a first reciprocal processing section that performs reciprocal processing on power to output a signal; an error arithmetic section that arithmetically operates an error of the compensated signal; a subtractor that subtracts the signal output from the first reciprocal processing section from the error; a second reciprocal processing unit that performs reciprocal processing on the signal output from the subtractor to output a signal; a first multiplier that multiplies the power and the signal output from the second reciprocal processing unit together to output a signal; and a second multiplier that multiplies the signal compensated by the propagation path compensation unit and the signal output from the first multiplier together to output a signal to an adder.

Abstract: A receiving device includes: a propagation path compensation unit that compensates a signal by using a propagation path characteristic; a power arithmetic section that arithmetically operates power of a signal; a first reciprocal processing section that performs reciprocal processing on power to output a signal; an error arithmetic section that arithmetically operates an error of the compensated signal; a subtractor that subtracts the signal output from the first reciprocal processing section from the error; a second reciprocal processing unit that performs reciprocal processing on the signal output from the subtractor to output a signal; a first multiplier that multiplies the power and the signal output from the second reciprocal processing unit together to output a signal; and a second multiplier that multiplies the signal compensated by the propagation path compensation unit and the signal output from the first multiplier together to output a signal to an adder.

Abstract: A receiver includes: an extraction unit configured to extract a pilot signal of a received symbol including the pilot signal and a data signal, the symbol being one of sequential symbols received by the receiver; an estimation unit configured to calculate a channel estimation value indicating an estimation result of a channel impulse response in the symbol, based on the pilot signal by executing a decoding algorithm of compressed sensing; a reduction unit configured to perform a predetermined operation on each of channel estimation values of symbols of a predetermined number among the symbols, the operation reducing an error component included in the channel estimation value; and a canceller unit configured to cancel an inter-carrier interference component included in any one of symbols of the predetermined number, based on the channel estimation value in which the error component is reduced.

Abstract: A receiver for receiving a frame including a pilot signal and a data signal, referring to an impulse response of a propagation path estimated from the pilot signal, and performing compensation processing on the data signal, the receiver includes: an extraction unit configured to extract the pilot signal of the frame; and an estimation unit configured to execute orthogonal matching pursuit (OMP) method which is a decoding algorithm for compressive sensing and to estimate the impulse response from the pilot signal, wherein the estimation unit refers to a pilot signal of a first frame, estimates an impulse response, determines position information on the estimated impulse response, refers to a pilot signal corresponding to the determined position information, of a second frame subsequent to the first frame, estimates an impulse response, and determines position information on the estimated impulse response.

Abstract: A receiver for receiving a frame including a pilot signal and a data signal, referring to an impulse response of a propagation path estimated from the pilot signal, and performing compensation processing on the data signal, the receiver includes: an extraction unit configured to extract the pilot signal of the frame; and an estimation unit configured to execute orthogonal matching pursuit (OMP) method which is a decoding algorithm for compressive sensing and to estimate the impulse response from the pilot signal, wherein the estimation unit refers to a pilot signal of a first frame, estimates an impulse response, determines position information on the estimated impulse response, refers to a pilot signal corresponding to the determined position information, of a second frame subsequent to the first frame, estimates an impulse response, and determines position information on the estimated impulse response.

Abstract: A signal processing circuit includes a PLL circuit configured to lock to a frequency contained in an input signal, a signal generating circuit configured to detect a direct-current component of a signal that is obtained by shifting frequencies of the input signal by a displacement equal to the locked frequency, and to generate a signal that has an amplitude responsive to the detected direct-current component and that has the same frequency and phase as a signal component of the locked frequency of the input signal, and a subtraction circuit configured to subtract the signal generated by the signal generating circuit from the input signal.

Abstract: A wireless receiving apparatus includes a spurious component extraction unit, and a spurious cancellation unit. The spurious component extraction unit is configured to cancel a desired wave with a multi-antenna configuration, and extract spurious components. The spurious cancellation unit is configured to cancel spurious in received signals by using the spurious components extracted. A first correlation unit in the spurious component extraction unit finds a correlation between an output of the spurious extraction unit and an output of the spurious cancellation unit.

Abstract: An reception device includes: a fast-fourier-transform (FFT) circuit to FFT a first Orthogonal Frequency Division Multiplexing (OFDM) signal including a plurality of first symbols with a guard interval and a valid symbol using a plurality of FFT windows that includes different timings within a symbol length period; a propagation channel estimation circuit to extract pilot signals from the fast-fourier-transformed first OFDM signal, and estimate a plurality of propagation channel characteristics of the plurality of first symbols based on the pilot signals; and a propagation channel compensation circuit to obtain a propagation channel characteristic of a second symbol without a pilot signal based on the plurality of propagation channel characteristics and remove the propagation channel characteristic of the second symbol from a second OFDM signal obtained by fast-fourier-transforming the second symbol.

Abstract: A signal processing circuit includes a PLL circuit configured to lock to a frequency contained in an input signal, a signal generating circuit configured to detect a direct-current component of a signal that is obtained by shifting frequencies of the input signal by a displacement equal to the locked frequency, and to generate a signal that has an amplitude responsive to the detected direct-current component and that has the same frequency and phase as a signal component of the locked frequency of the input signal, and a subtraction circuit configured to subtract the signal generated by the signal generating circuit from the input signal.

Abstract: A radio communication system including a first terminal apparatus group for performing a reception by using a first radio resource and a transmission by using a second radio resource; and a second terminal apparatus group for performing the reception by using the second radio resource and the transmission by using the first radio resource, for performing a direct radio communication. The system includes a first terminal which belongs to the first terminal apparatus group and transmits allocation request of transmission band in the second radio resource by using the second radio resource; and a second terminal which belongs to the second terminal apparatus group, receives the allocation request transmitted from the first terminal, and transmits information indicating allocation of the transmission band for the first terminal, wherein the first terminal transmits data by using the allocated transmission band in the second radio resource.

Abstract: A wireless receiving apparatus includes a spurious component extraction unit, and a spurious cancellation unit. The spurious component extraction unit is configured to cancel a desired wave with a multi-antenna configuration, and extract spurious components. The spurious cancellation unit is configured to cancel spurious in received signals by using the spurious components extracted. A first correlation unit in the spurious component extraction unit finds a correlation between an output of the spurious extraction unit and an output of the spurious cancellation unit.

Abstract: A data allocation method in a wireless communication system in which data is allocated in both a time axis direction and frequency axis direction, and data is transmitted between a mobile station and base station according to an allocated schedule, the allocation method including: measuring propagation path information between the mobile station and the base station; and modifying an allocation width of a burst in the time axis direction or in the frequency axis direction based on the propagation path information.

Abstract: The MS detects a difference in timing or frequency between a reference signal being any one of the received signals from a plurality of BSs and each of the other received signals, notifies the results of detection to BSs other than the source BS of the reference signal, and the BSs other than the source BS of the reference signal control the timing or frequency of transmission of the signal to be received by other MSs other than the MS on the basis of the results of the detection.

Abstract: An reception device includes: a fast-fourier-transform (FFT) circuit to FFT a first Orthogonal Frequency Division Multiplexing (OFDM) signal including a plurality of first symbols with a guard interval and a valid symbol using a plurality of FFT windows that includes different timings within a symbol length period; a propagation channel estimation circuit to extract pilot signals from the fast-fourier-transformed first OFDM signal, and estimate a plurality of propagation channel characteristics of the plurality of first symbols based on the pilot signals; and a propagation channel compensation circuit to obtain a propagation channel characteristic of a second symbol without a pilot signal based on the plurality of propagation channel characteristics and remove the propagation channel characteristic of the second symbol from a second OFDM signal obtained by fast-fourier-transforming the second symbol.

Abstract: A receiving circuit includes: an analog-to-digital converter to convert an input signal in a certain bandwidth to a digital signal; a Fourier transformer to convert the digital signal from a time-domain signal to a frequency-domain signal; a band-elimination filter to extract an interference wave signal from the time-domain signal; and a filter control circuit to measure frequency characteristics of the interference wave signal so that the attenuation characteristics of the band-elimination filter has a attenuation characteristics opposite to the frequency characteristics in a direction.

Abstract: A radio communication system including a first terminal apparatus group for performing a reception by using a first radio resource and a transmission by using a second radio resource; and a second terminal apparatus group for performing the reception by using the second radio resource and the transmission by using the first radio resource, and a directly radio communication is performed, the system including: a first terminal which belongs to the first terminal apparatus group and transmits allocation request of transmission band in the second radio resource by using the second radio resource; and a second terminal which belongs to the second terminal apparatus group, receives the allocation request transmitted from the first terminal, and transmits information indicating allocation of the transmission band for the first terminal, wherein the first terminal transmits data by using the allocated transmission band in the second radio resource.

Abstract: A radio transmitter includes a signal generating unit that generates first and second OFDM (Orthogonal Frequency-Division Multiplexing) signals carrying the same information, and a phase shifter that controls a phase of the second OFDM signal based on a spectrum of a composite signal of the first and second OFDM signals.

Abstract: The MS detects a difference in timing or frequency between a reference signal being any one of the received signals from a plurality of BSs and each of the other received signals, notifies the results of detection to BSs other than the source BS of the reference signal, and the BSs other than the source BS of the reference signal control the timing or frequency of transmission of the signal to be received by other MSs other than the MS on the basis of the results of the detection.

Abstract: A data allocation method in a wireless communication system in which data is allocated in both a time axis direction and frequency axis direction, and data is transmitted between a mobile station and base station according to an allocated schedule, the allocation method including: measuring propagation path information between the mobile station and the base station; and modifying an allocation width of a burst in the time axis direction or in the frequency axis direction based on the propagation path information.