Abstract: A multiplexing/demultiplexing device has a phase difference detection part for detecting a phase difference from a reference frequency of a multiplexed signal and a reference frequency of each of input/output lines, an interpolation part for performing an interpolation on a digital transmitting/receiving signal of each of the input/output lines with a signal delayed by time corresponding to the phase difference for each of the input/output lines based on the phase difference detected by the phase difference detection part to obtain a digital transmitting/receiving signal sampled with the reference frequency of the multiplexed signal for each of the input/output lines, and a signal multiplexing/demultiplexing part for performing a multiplex/demultiplex of the digital transmitting/receiving signals of the input/output lines with use of the reference frequency of the multiplexed signal.

Abstract: Data multiplexing subcarrier identification signal generating means generates a data multiplexing subcarrier identification signal that identifies subcarriers with which data signals are to be multiplexed. Transmission signal generating means generates transmission signals by multiplexing data signals with subcarriers according to the data multiplexing subcarrier identification signal.

Abstract: A radio communication unit includes: a reference-signal extraction section that extracts a phase of a reference signal from a baseband signal; a frequency-shift calculation section that calculates a phase shift of the received reference signal with respect to time, and calculates a frequency shift of the received carrier frequency; and an estimation-range decision section that determines, based on the calculated frequency shift, an estimation range used in the frequency-shift calculation section for estimating the frequency shift in a next slot.

Abstract: A wireless communication apparatus with a plurality of antennas which receive a wireless reception signal from a secondary communication apparatus, and a combiner which combines signals from the plurality of antennas to form a combined signal or selects one of the signals from the plurality of antennas. A wireless communication apparatus with a plurality of antennas which transmits a wireless transmission signal to a secondary communication apparatus and a divider which divides a transmission signal into plurality of transmission signals to be transmitted by the plurality antennas or selects one of the plurality of antennas to transmit the transmission signal.

Abstract: A signal transmitted from a terminal is received by plural adjacent wireless base stations (110, 120), the signal received by antenna (111-3) of wireless base station (110) and antenna (121-1) of wireless base station (120) is amplified by reception amplification section (112-3, 122-1), the signal amplified by reception amplification section (122-1) is distributed by distribution section (123-1) to wireless base station (110), the signal distributed by distribution section (123-1) is combined with the signal amplified by reception amplification section (112-3) by demodulation section (114), and then demodulated.

Abstract: A radio base station which receives a first and a second communication channel from a radio communications device comprises a control circuit for detecting the reception quality of the first communication channel, conducting an inner-loop power control for controlling transmission power of the first communication channel from the radio communications device based on the reception quality and an inner-loop power control target value, and adding a power control offset to the inner-loop power control target value before starting a communication through the second communication channel.

Abstract: A device performs demodulation of control signals from multiple radio terminals, based on the correlations in the frequency domain between a predetermined code and the orthogonalized control signals and reference signals of the multiple radio terminals obtained by cyclic shifts of the predetermined code. The device includes: a demultiplexer which demultiplexes a reference signal component and a control signal component based on a correlation profile; a path detector which detects a path location or path locations for each radio terminal based on the power values of the reference signal components; extractor which extracts the correlation values of the reference signal components and the correlation values of the control signal components, respectively; and RAKE combiner which combines the extracted values.

Abstract: A pattern detection circuit for performing pattern detection on input signals from a communication terminal, includes a frequency domain transformer that transforms input signals into frequency domain signals; a frequency extractor that extracts frequency components of the frequency domain signals; and a pattern detector that performs the pattern detection on the input signals based on cross-correlation values in frequency domain between the extracted frequency components and predetermined patterns.

Abstract: An active set control method for handover operation in a CDMA communications system in which propagation conditions of an uplink channel and a downlink channel for an access link of cell are different, provides that when a cell is deleted from the active set based on a request of a base station which has detected a degraded signal of the uplink channel, a predetermined period of time is to be counted for inhibiting addition of the same cell in the active set based on a request of a mobile terminal which has detected a satisfied signal of the downlink channel, thereby preventing the deletion and addition of the cell in the active set from successive operations in a short time.

Abstract: To achieve the optimal power control of a system in an MIMO communication method. When decoding in accordance with a receiving algorithm of the MIMO communication method in plural receivers, each receiver acquires the reception power level of a received signal from a transmitter paired with the receiver, and generates a transmitter power control signal based on a comparison result of comparing the reception power with a predetermined value. For example, if the reception power level is lower than the predetermined value, a transmitter power control signal of instructing to increase the transmitter power is generated, or otherwise, a transmitter power control signal of instructing to decrease the transmitter power is generated. The generated control signal is transmitted from the receiver to the transmitter paired with the receiver. Each transmitter controls the transmitter power in accordance with the received control signal.

Abstract: Disclosed is a wireless communication system in which a mobile station transmits a plurality of reference signals upon placing the reference signals in temporally spaced-apart relation in at least one of information transmission units wirelessly transmitted in conformity with a hopping period, and a base station receives an information transmission unit that has been transmitted from the mobile station and, if this information transmission unit is one that includes a plurality of the reference signals, obtains a phase fluctuation from the plurality of reference signals and obtains a frequency deviation from the phase fluctuation.

Abstract: A reception quality estimation device includes: a correlation extractor for extracting correlation between multiplexed reception reference signals received from the plurality of user terminals and a predetermined reference signal sequence, wherein extracted correlation corresponds to each user terminal; a received power calculator for calculating received signal power from the extracted correlation corresponding to each user terminal; a total received power calculator for calculating total received signal power by summing up the received signal power for all the plurality of user terminals; a noise power estimator for estimating noise power based on the total received signal power and total received power of multiplexed reception reference signals; and a reception quality calculator for calculating the reception quality of each user terminal based on the received signal power and the noise power.

Abstract: Base stations (100-1 to 100-3) communicate with terminals (102-1 to 102-2), divides a used frequency into a plurality of frequency blocks, and assigns the divided frequency block to terminal (102-1 to 102-2), in which a position at which terminal (102-1 to 102-2) exists is determined, and if it is determined that terminal (102-1 to 102-2) exists at the edge of cell (101-1 to 101-3), the assigned frequency block is set as a cell edge frequency block that is to be dynamically assigned at the edge of cell (101-1 to 101-3). In addition, if the cell edge frequency block has already been assigned to another terminal, this cell edge frequency block is assigned to terminal (102-1 to 102-2).

Abstract: A mobile communication system and a signal transfer method, which use a signal having a preferred signal length from the implementation view point, are disclosed. The sending device sends a notify signal in which the time length is defined to be such a time that the number of samples when sampling at the sampling frequency becomes the product of the exponentiation of the predetermined number of prime numbers from the smaller number. The receiving device detects the notify signal by performing predetermined signal processing on the signal received from the sending device.

Abstract: A wireless communication system comprising a base station and a terminal station. The base station extracts paths having a power level that exceeds a predetermined threshold value from delay profiles of said terminal station as available paths, selects a path having a maximum power or a first path from said available paths as a reference path, calculates time difference between an arrival time of said reference path and a predetermined maximum arrival time, and transmits the result to said terminal station as a transmission timing control signal. The terminal station adjusts the transmission timing to the base station according to said time difference. The base station transmits the transmission timing control signal only when the base station detects the reference path.

Abstract: In a wireless communication system, a control unit (17) of a base station (1) sets a frequency hopping cycle longer than a predetermined value during a certain measurement interval in which an measurement of a frequency drift is conducted, allowing reception of a plurality of reference signals of the same frequency in receiving an uplink signal from a mobile station (2). The control unit (17) controls a reference signal extraction unit (15) and a reference signal phase difference calculation unit (16) so as to measure, based on the plurality of reference signals, the phase shift amount of a received signal at the same frequency. Thus, the wireless communication system can measure the phase shift amount by controlling the frequency hopping.

Abstract: A wireless base station sends transmission parameters that specify a control signal coding rate and a data signal coding rate which satisfy a BLER (Block Error Rate) required for a control signal and a data signal in a TTI (Transmit Time Interval) scheduled in response to a transmission request from a mobile station. In the specified TTI, the mobile station applies the coding rates, included in the transmission parameters and specified for the control signal and the data signal, to the control signal and the data signal, time-division multiplexes the coded control signal and coded data signal to generate constant transmission-power transmission data, and sends the generated transmission data to a wireless base station via PUSCH.

Abstract: An interference power measuring circuit in a base station measures the interference power in a cell that the base station belongs to. When the measured interference power is larger than a predetermined value, the transmitter in the base station transmits the interference information for each frequency used in the FDMA communication system to a base station in a neighboring cell. The base station in the neighboring cell instructs user equipment that communicates the base station to reduce a transmission power.

Abstract: An amplitude limiting circuit for limiting the amplitude of a signal input to a power amplifier includes an amplitude converter, determination unit, peak detector, window filter, delay circuit, and multiplier. The amplitude converter calculates the amplitude value of an input signal. The determination unit detects an interval in which the amplitude value of the input signal exceeds a preset threshold. The peak detector detects the peak time and amplitude when the maximum amplitude appears. The window filter limits the amplitude value to not more than the threshold by using the peak value output from the peak detector. The delay circuit delays the input signal such that the peak time output from the peak detector coincides with the time when the output from the window filter exhibits the minimum value. The multiplier multiplies an output signal from the delay circuit by a window function. A CDMA communication apparatus is also disclosed.

Abstract: A nonlinear distortion compensating circuit in which a digital value expressing the amplitude of an input signal is divided into upper and lower bits. Only the upper bits are input to a first memory address. A value obtained by adding 1 to the upper bits is input to a second memory address, or, an interpolation circuit to which the upper bits are input, inputs the upper bits to a first memory storing data corresponding to an even numbered address and a second memory storing data corresponding to an odd numbered address, and performs interpolation by adding outputs from the memories by weighting these outputs in accordance with a value expressed by the lower bits. The input signal is multiplied by the obtained value. An interpolation circuit output is an orthogonal coordinate expression (combination of a real part and imaginary part) or polar coordinate expression (combination of an amplitude and phase).