Abstract: Channel fluctuation values on propagation paths of modulated signals transmitted from a plurality of antennas are estimated, an eigenvalue of a channel fluctuation matrix created with the above-mentioned channel fluctuation values as elements is found in order to relate antenna received signals to modulated signals, and using that eigenvalue, receiving antenna selection, combining of modulated signals, and weighting processing on soft decision decoded values, are performed, and modulated signals are demodulated. By this means, it is possible to perform demodulation processing based on the effective reception power of a modulated signal (that is to say, the essential reception power, of the reception power obtained by a receiving apparatus, that can be effectively used when demodulating a modulated signal), enabling the precision of demodulation of modulated signals to be improved.

Abstract: Provided is a discrete filter capable of increasing degree of freedom of design including a DC gain. A sampling mixer (100) includes: a control signal generation unit (104) which generates a control signal including an SO signal; a Ch (6) which successively integrates reception signals sampled by an LO signal frequency as discrete signals; a plurality of Cr (7, 8) which successively integrate discrete signals at a timing based on the control signal; Cb (15) which alternately integrates the discrete signals successively integrated by the respective Cr (7, 8); and a gain control capacitance unit (110) which has gain control capacitors (44, 45, 46) connected in parallel to the respective Cr (7, 8) and integrating the discrete signal and a reset switch (47) for resetting the discrete signal of the gain control capacitors (44, 45, 46) integrated in the past, upon connection between one end of Cr (7) and Cb (15).

Abstract: Provided is a discrete filter capable of adjusting the number of notches and the notch frequency and easily eliminating a particular frequency component. In a sampling mixer (100), a control signal generation unit (104) generates a plurality of control signals having the same frequency and different phases. A convolution capacity unit (110) integrates the discrete signals obtained by sampling reception signals by using convolution capacitors at a timing based on the control signals. The signals integrated by the convolution capacitors are successively emitted at the timing based on a control signal other than the control signals used for the integration timing. Cb (15) integrates the emitted discrete signals.

Abstract: A sampling mixer includes TAs (transconductance amplifiers), an in-phase mixer section connected to the TA and the TA, an opposite-phase mixer section connected in parallel with the in-phase mixer section, and a signal generator for generating a control signal for the in-phase mixer section and the opposite-phase mixer section respectively. The IIR filter using signals that underwent a current conversion by using the different transconductances is constructed, so that the filter characteristic can be designed by a weighting of the transconductance in addition to a capacitance ratio. As a result, the wide-band filter characteristic and the band-pass filter characteristic can be obtained, and deterioration of the receiving sensitivity can be suppressed by designing the filter characteristic suitable for the radio communication system.

Abstract: A communication device selects an optimal modulation method even when a propagation path condition is changed. In the communication device, a second communication device has a transmission path condition estimation unit for estimating the propagation path condition change speed and a communication quality estimation unit for modifying the communication quality estimation method according to the speed of the change of the propagation path condition and for estimating the communication quality according to the modified estimation method. The information on the estimated propagation path condition and the information on the communication quality are transmitted from a transmission processing unit, and an adaptive modulation control unit of the first communication device sets a condition for selecting the modulation method and decides the modulation method according to the set condition and the information on the communication quality.

Abstract: A transmitting apparatus includes a modulation signal generating section that generates a modulation signal by modulating transmission data using one of a plurality of modulation schemes. The plurality of modulation schemes include a first modulation scheme, a second modulation scheme, and a third modulation scheme, where the first modulation scheme has maximum m-ary modulation value, the second modulation scheme has a lower m-ary modulation value than the first modulation scheme, and the third modulation scheme has a lower m-ary modulation value than the second modulation scheme. The transmitting apparatus also includes a pilot signal generating section that generates a pilot signal having one of a plurality of amplitudes, the pilot signal having a lower amplitude than a maximum amplitude of the first modulation scheme.

Abstract: The present invention aims at providing a sampling filter capable of changing a filtering characteristic without use of a complicate waveform as a control signal. A sampling filter 100 has a control section 140, a plurality of integrators, and a plurality of switches. An input current is accumulated in a plurality of capacitors in one clock; adds up electric charges accumulated in the integrators in several preceding clocks to one preceding clock; and outputs a result of addition. When electric charges are accumulated in the integrators in each clock, output electric charges can be subjected to, while being weighted, addition by switching an electric current to be input, so that the filtering characteristic is changed.

Abstract: A sampling mixer includes TAs (transconductance amplifiers), an in-phase mixer section connected to the TA and the TA, an opposite-phase mixer section connected in parallel with the in-phase mixer section, and a signal generator for generating a control signal for the in-phase mixer section and the opposite-phase mixer section respectively. The IIR filter using signals that underwent a current conversion by using the different transconductances is constructed, so that the filter characteristic can be designed by a weighting of the transconductance in addition to a capacitance ratio. As a result, the wide-band filter characteristic and the band-pass filter characteristic can be obtained, and deterioration of the receiving sensitivity can be suppressed by designing the filter characteristic suitable for the radio communication system.

Abstract: A radio communication apparatus that is capable of switching modulation schemes. The radio communication apparatus includes a QPSK modulation signal generator, a QAM modulation signal generator, a transmission radio, and a common transmission power amplifier. The QPSK modulation signal generator modulates transmission data by a QPSK modulation scheme and outputs a QPSK modulation signal. The QAM modulation signal generator modulates transmission data by a QAM scheme and outputs a QAM modulation signal. The transmission radio receives the QPSK modulation signal or the QAM modulation signal and outputs a transmission signal, which is amplified by the common transmission power amplifier.

Abstract: Multimode wireless communication apparatus supports plural wireless communication methods and includes synchronization detecting part. Digital signals output from first A/D part and second A/D part are combined by synchronization detecting part. Synchronization detecting part converts sampling frequencies of respective digital signals and performs other processes when combining digital signals. Synchronization detecting part detects synchronization timing for plural wireless communication methods by plurally performing correlation operation corresponding to respective wireless communication methods for digital signals combined, thereby providing a multimode wireless communication apparatus with its size and power consumption reduced.

Abstract: A sampling filter device wherein the filter characteristic is variable without using a control signal of a complicated waveform is provided. A sampling filter device 105 has integration capacitors 130 and 131, an integration time adjustment section 180, and a plurality of switches 100, 101, 110, and 111. Input current is integrated in different time duration with one clock and is stored in the integration capacitors 130 and 131 and charges stored in the integration capacitor from several clocks before to one clock before are added and the result is output. When charge is stored in the integration capacitors 130 and 131 with each clock, the integration time duration is changed, whereby it is made possible to weight and add output charge and the filter characteristic changes.

Abstract: Based on a received signal of a wireless communication system currently used for communication, a communication quality in a case of switching to another wireless communication system for communication is efficiently and precisely estimated. A communication quality estimating part (201) subjects both a known signal received, by use of a first wireless communication system, from a radio part (200) and a reference signal outputted from a reference signal storage part (203) to a conversion processing unique to a second wireless communication system for comparison, thereby artificially estimating the communication quality in a case of using a second wireless communication system for communication under the same wireless transmission path environment.

Abstract: A radio communication apparatus that is capable of switching modulation schemes. The radio communication apparatus includes a QPSK modulation signal generator, a QAM modulation signal generator, a transmission radio, and a common transmission power amplifier. The QPSK modulation signal generator modulates transmission data by a QPSK modulation scheme and outputs a QPSK modulation signal. The QAM modulation signal generator modulates transmission data by a QAM scheme and outputs a QAM modulation signal. The transmission radio receives the QPSK modulation signal or the QAM modulation signal and outputs a transmission signal, which is amplified by the common transmission power amplifier.

Abstract: A reception quality estimating apparatus, a wireless communication system and a reception quality estimating method wherein the communication qualities in a case where different communication schemes are used to have communication can be artificially estimated without switching the communication schemes to be used for the communication. A wireless communication apparatus (100) comprises a reception processing part (110), an artificially decoded error estimating part (120), and an upper-order layer processing part (130). An orthogonal vector data sequence (152), which is generated by a demodulating part (111) from a received signal (150), for each symbol in the current modulation scheme is used to artificially generate a likelihood metric value (155) obtained in a case of using a second communication scheme, which has a larger number of modulation multi-values than the current communication scheme, to perform a signal point arrangement.

Abstract: A variable delay circuit (101) generates a plurality of delay signals (D(1), D(2), . . . , D(n)). An output holding circuit (102) receives the plurality of delay signals (D(1), D(2), . . . , D(n)) in synchronization with a transition of a reference signal (Sref). A selector (104) provides an input signal (Sin) to the variable delay circuit (101) in a normal mode, and provides one of the plurality of delay signals (D(1), D(2), . . . , D(n)) to the variable delay circuit (101) in a calibration mode. A frequency measurement circuit (105) counts the number of transitions of one of the plurality of delay signals (D(1), D(2), . . . , D(n)) during a predetermined frequency measurement period. In the calibration mode, a delay-amount calibration circuit (106) adjusts a delay time of the variable delay circuit (101) so that the number of transitions counted by the frequency measurement circuit (105) approaches a target value corresponding to a frequency of the input signal (Sin).

Abstract: Provided is a discrete filter capable of increasing degree of freedom of design including a DC gain. A sampling mixer (100) includes: a control signal generation unit (104) which generates a control signal including an SO signal; a Ch (6) which successively integrates reception signals sampled by an LO signal frequency as discrete signals; a plurality of Cr (7, 8) which successively integrate discrete signals at a timing based on the control signal; Cb (15) which alternately integrates the discrete signals successively integrated by the respective Cr (7, 8); and a gain control capacitance unit (110) which has gain control capacitors (44, 45, 46) connected in parallel to the respective Cr (7, 8) and integrating the discrete signal and a reset switch (47) for resetting the discrete signal of the gain control capacitors (44, 45, 46) integrated in the past, upon connection between one end of Cr (7) and Cb (15).

Abstract: The sampling filter apparatus 100 includes the first sampling switch 130, the second sampling switch 131, the first integrator 1500 for integrating the charge input from the first sampling switch, the second integrator 1501 for integrating the charge input from the second sampling switch, a plurality of integrators connected to both of the first integrator and the second integrator via a charging switch, respectively, the control section 140, a plurality of charging switches, and a plurality of discharge switches. A charge input from the sampling switch 130, a charge accumulated in the capacitor 1500 and a charge accumulated in a capacitor 1510 are shared by the capacitor 1500, the capacitor 1510 and the capacitor 1530, and the charge accumulated in the capacitor 1530 is output.

Abstract: A sampling filter of such circuitry as not requiring a high frequency REF signal even if the number of decimation is decreased. In the sampling filter, the rotate capacitor in each switched capacitor circuit including Cr (7a-7d) arranged in four parallel arrays operates in four phases of integration, discharge, reset and feedback different from each other at the same timing. Consequently, a control signal for driving the switched capacitor circuit is used commonly. As a result, the circuit scale of a DCU (104) is reduced and the frequency of the REF signal can be lowered to the frequency of an LO signal even in operation without decimation.

Abstract: A radio communication apparatus to be changed in function by software, when downloading software from a download server, first downloads software limited in operation and then configures a software radio section. After the configuration and the operation confirmation have been normally completed, execution-allowing key information is requested and received. Using it, reconfiguration is carried out in part thereby enabling all the operations. Accordingly, it is possible to safely carry out a download and a setting update of software to the radio communication apparatus.

Abstract: Provided is a discrete filter capable of adjusting the number of notches and the notch frequency and easily eliminating a particular frequency component. In a sampling mixer (100), a control signal generation unit (104) generates a plurality of control signals having the same frequency and different phases. A convolution capacity unit (110) integrates the discrete signals obtained by sampling reception signals by using convolution capacitors at a timing based on the control signals. The signals integrated by the convolution capacitors are successively emitted at the timing based on a control signal other than the control signals used for the integration timing. Cb (15) integrates the emitted discrete signals.