Patent application number | Description | Published |
20090010313 | Receiver and Reception Processing Method - A receiver including: a delay profile generating unit to generate a delay profile from a received signal; combining unit operable to combine multiple received signals with different timings; a determining unit to determine whether or not the propagation environment of the received signals is multi-path, based on the delay profile; and a control unit operable to exclude any signal with timing whose power is equal to or lower than a predetermined threshold in the delay profile from the combining, upon the determination not being multi-path. | 01-08-2009 |
20090213969 | Wireless Communication Device, Equalizer, Computer-Readable Medium Storing Program for Obtaining Weight Coefficients in the Equalizer, and Process for Obtaining Weight Coefficients in the Equalizer - In an equalizer arranged in a wireless communication device: information on correlation in one or more first wireless signals is generated; a channel vector is generated on the basis of the one or more first wireless signals; an extended correlation matrix which contains a correlation matrix indicating the information on correlation and is extended so as to become a circulant matrix is generated; an extended channel vector is generated by extending the channel vector so that the extended channel vector contains elements of the channel vector and has rows the number of which is identical to the number of rows of the extended correlation matrix; and weight coefficients are calculated as a solution, in the frequency domain, of an equation expressed by the extended correlation matrix and the extended channel vector, where the solution is obtained by solving the equation. | 08-27-2009 |
20100009636 | MOBILE STATION AND BASE STATION - A mobile station provided with first and second antennas with a distance therebetween includes a reception quality measurement unit that measures, when the mobile station moves in a direction from a location of the first antenna toward a location of the second antenna, a reception quality of a radio signal provided by a base station via the second antenna; a notification unit that notifies the base station of the reception quality measured by the reception quality measurement unit; and a reception processing unit that performs a reception process of a radio signal that is transmitted by the base station, which performs adaptive modulation based on the reception quality notified by the reception unit, and is received by the first antenna. | 01-14-2010 |
20100020855 | CONTROL APPARATUS FOR AND CONTROL METHOD OF EQUALIZER, AND WIRELESS TERMINAL HAVING THAT CONTROL APPARATUS - A channel estimation value of each path timing is determined, a path timing, the channel estimation value of which is to be set to zero, is determined based on a reception power of each path timing and a predetermined power threshold (P | 01-28-2010 |
20100034311 | WIRELESS COMMUNICATION APPARATUS AND WIRELESS COMMUNICATION CONTROLLING METHOD - To reduce the influence of Doppler shift, with the sub-carrier interval being widened in a high-frequency band, transmission timings of frames for every frequency band are matched each other. By matching the frame transmission timings, at the receiving side, once the modulation timing in one frequency band is detected, the modulation timing at another frequency band can be obtained. Therefore, demodulation can be simplified. To match the frame transmission timings, the CP length is adjusted, for example. | 02-11-2010 |
20100246477 | RETRANSMISSION METHOD, WIRELESS COMMUNICATION APPARATUS, AND RELAY STATION - A retransmission method in a mobile communication system includes performing a first transmission of data from a first wireless communication apparatus to a second wireless communication apparatus through at least one relay station by wireless relaying; and performing retransmission processing of retransmitting the data through fewer relay stations than the first transmission, or without using any relay station, where the second wireless communication apparatus receives data transmitted based on the retransmission processing. | 09-30-2010 |
20110075711 | WIRELESS RECEIVER, WIRELESS COMMUNICATION SYSTEM, AND WIRELESS COMMUNICATION METHOD - A wireless receiver receives a signal obtained by multiplexing a plurality of signals that include a synchronization signal that is spread using a non-orthogonal code not orthogonal to a code for spreading other signals other than the synchronization signal. Then, in a case when the signals other than the synchronization signal are the target signals for decoding, the wireless receiver performs despreading with respect to the received signal using the synchronization signal and estimates the signal amplitude of the non-orthogonal code. Subsequently, the wireless receiver eliminates the spread synchronization signal from the received signal using the estimated signal amplitude of the non-orthogonal code and using the synchronization signal. Eventually, the wireless receiver performs despreading and demodulation with respect to the signal having the spread synchronization signal eliminated therefrom and decodes the target signals for decoding. | 03-31-2011 |
20110216644 | RECEIVING APPARATUS AND METHOD - A receiving apparatus includes a first transform unit configured to perform orthogonal transform on a time-domain input signal and perform saturation when an overflow occurs to transform the input signal into a plurality of frequency-domain signals, a second transform unit configured to perform orthogonal transform on the time-domain input signal while restricting the number of bits during orthogonal transform and continue operations while not performing saturation when at least one of the operations overflows and leaving the operation overflowing to transform the input signal into a plurality of frequency-domain signals, and a bit restricting control unit configured to control the number of bits during orthogonal transform by the second transform unit based on output signals of the first transform unit. | 09-08-2011 |
20110216854 | RECEIVING DEVICE AND METHOD - A receiving device includes a FFT unit performing FFT on an input signal of a time domain to transform the input signal into a plurality of signals of frequency domains and outputting the plurality of signals of the frequency domains, a signal extracting unit extracting a signal with a power that is greater than a threshold value from among the plurality of signals of the frequency domains output from the first FFT unit and outputting the extracted signal, an IFFT unit performing IFFT on the extracted signal output from the signal extracting unit, a subtracting unit subtracting the extracted signal output from the IFFT unit from the input signal and outputs a subtracted signal, and a second FFT unit transforming the subtracted signal output from the subtracting unit into a signal of the frequency domain by performing the FFT on the subtracted signal output from the subtracting unit. | 09-08-2011 |
20120128100 | FREQUENCY SHIFT CIRCUIT AND COMMUNICATION DEVICE - A frequency shift circuit that shifts the frequency of an input signal using a rotor corresponding to a predetermined phase rotation amount, the frequency shift circuit includes a table look-up unit that includes a plurality of tables that store complex data and outputs the complex data for each table based on address information, a complex multiplication circuit that complex-multiplies the complex data which have been output from the table look-up unit for each table, a deletion circuit that generates a rotor corresponding to a phase rotation amount which is based on a result of complex-multiplication executed, and a calculation circuit that calculates the address information for each table such that exp (2 π j θ) is obtained as the result of complex multiplication executed based on rotation angle information θ. | 05-24-2012 |
20130039400 | TRANSMITTING APPARATUS, RECEIVING APPARATUS, RADIO COMMUNICATION SYSTEM, AND RADIO COMMUNICATION METHOD - A transmitting apparatus includes multiple antennas between which an antenna interval is variable; and a transmitter that transmits a pilot signal using an antenna selected from among the antennas and based on a correlation value representing correlation between the antennas. | 02-14-2013 |
20140119225 | BASE STATION, WIRELESS TERMINAL, AND WIRELESS COMMUNICATION SYSTEM - A measuring unit measures channel values of propagation channels based on a pilot signal transmitted from a wireless terminal. An interpolation coefficient calculating unit calculates interpolation coefficients used to estimate channel values for one of antennas of the wireless terminal by using channel values for the rest of the antennas of the wireless terminal, which channel values are measured by the measuring unit. An estimate value calculating unit estimates the channel values for the one of the antennas of the wireless terminal based on the interpolation coefficients calculated by the interpolation coefficient calculating unit and the channel values for the rest of the antennas of the wireless terminal measured by the measuring unit. | 05-01-2014 |
20140133541 | WIRELESS COMMUNICATION APPARATUS AND WIRELESS COMMUNICATION METHOD - A wireless communication apparatus includes a wireless section configured to receive a plurality of signals via a plurality of antennae from a transmitting device having another plurality of antennae; and a demodulation section configured to apply QR decomposition to a channel matrix generated based on the received signals from the wireless section, to extract a plurality of weight coefficients corresponding to a symbol to be demodulated from a unitary matrix Q, to filter the received signals weighted with the weight coefficients, and to separate the filtered received signals based on a submatrix of an upper triangular matrix R. | 05-15-2014 |
20140133611 | WIRELESS COMMUNICATION APPARATUS AND ONE-PATH STATE DETERMINATION METHOD - A wireless communication apparatus includes a wireless unit configured to receive a radio signal; and a signal processing unit configured to detect a phase shift between a detection timing of a path relevant to the received signal at the wireless unit and a path timing of the received signal, to calculate interference power by a first path having a maximum power value based on the phase shift, to calculate power of one or more second paths other than the first path based on the interference power, and to determine whether the received signal is received in a one-path state or a multi-path state based on the power value of the first path and the power values of the one or more second paths. | 05-15-2014 |
20140233682 | WIRELESS COMMUNICATION APPARATUS AND COMMUNICATION METHOD - A wireless communication apparatus receiving a signal transmitted from multiple transmission antennas by multiple reception antennas, includes a rotational component removal unit to remove rotational components from a channel matrix representing a characteristic of a transmission path between the multiple transmission antennas and reception antennas, the channel matrix being generated based on the reception signal; multiple signal separation units including at least a signal separation unit to use a first signal separation algorithm for a demodulation process of the reception signal, and a signal separation unit to use a second signal separation algorithm for the demodulation process of the reception signal; and a control unit to execute control for determining one of the multiple signal separation units to be used for the demodulation process of the reception signal, based on a predetermined component of the channel matrix having the rotational components removed. | 08-21-2014 |
20150085744 | RETRANSMISSION METHOD, WIRELESS COMMUNICATION APPARATUS, AND RELAY STATION - A retransmission method in a mobile communication system includes performing a first transmission of data from a first wireless communication apparatus to a second wireless communication apparatus through at least one relay station by wireless relaying; and performing retransmission processing of retransmitting the data through fewer relay stations than the first transmission, or without using any relay station, where the second wireless communication apparatus receives data transmitted based on the retransmission processing. | 03-26-2015 |