Abstract: A cell search determination circuit is provided which is capable of reducing misdetections in the identification of a scramble code number. A mobile station in W-CDMA cellular communications confirms a scramble code identified by cell search.

Abstract: A multicarrier receiver that receives N carrier frequencies therein comprises N A/D converters each of which analog-digital converts a receive signal at a sample rate fs for each carrier, N quadrature detectors which receive outputs sent from the N A/D converters therein and digitally quadrature-detect the outputs, respectively, 2N LPFs which allow only desire bands of outputs of the N quadrature detectors to pass therethrough, and N delay time correcting means each of which corrects a processing delay time deviation for each carrier inside the multicarrier receiver in a time unit of less than 1/fs using a fractional delay filter. The delay time correcting means has, for example, an M-stage shift register which operates at fs and generates a delay of M/fs, and a fractional delay filter which operates at fs and includes an even number of tap coefficients and which generates a delay different from M/fs by 0.5/fs.

Abstract: A telecommunications device is provided that enables monitoring of the directivity of a wireless communications system that wirelessly transmits signals using multiple communications antennas while controlling the overall directivity of the multiple antennas. At least one monitor antenna, installed separately from multiple communications antennas controlled to achieve a prescribed overall directivity, wirelessly receives signals from the multiple communications antennas. A directivity information acquisition mechanism uses the signals received by the monitor antenna to acquire information regarding the overall directivity of the multiple communications antennas.

Abstract: The present invention provides a transmitting apparatus equipped with a modulator, a frequency converter that up-converts a modulated signal (or digital IF signal) of a baseband, and an amplifier that amplifies a transmit signal lying in a radio frequency band to a desired signal level. In the transmitting apparatus, a controller including a level determinater and a bias setter is provided with a limiter setter. The level determinater and bias setter of the controller setter perform dynamic bias control of the amplifier. Further, the limiter setter changes the setting of a threshold value of the limiter according to an average level of an input signal.

Abstract: A receiver that uses multiple antennas to receive signals arriving over multiple paths and is configured for enhanced received signal path detection accuracy and improved reception quality includes a receive weight generating circuit that generates receive weights for every antenna based on signals received from the antennas, a summing circuit that calculates sums of results obtained by multiplying the signals from the antennas and the receive weights of the individual antennas generated by the receive weight generating circuit and path detection circuit that detects the paths of the received signals based on the sums calculated by the summing circuit.

Abstract: To provide an amplifying device which is reduced in size, weight and cost and which can improve the distortion compensation performance. In the amplifying device, input signals are each subjected to digital orthogonal modulation using an IF and further to offset rotation processing in digital orthogonal modulators, then bifurcated into a main signal system and a control system, and detection of a power value is performed at an IF band in a power detecting section of the control system. Therefore, offset rotation processing of the input signals in the power detection is not required, so that a structure for matching phases of a multi-carrier signal and a power value signal is not required, resulting in improving the distortion compensation performance without using an analog delay line.

Abstract: A communication device for transmitting and/or receiving signals by using a communication antenna includes signal characteristic information detection means for detecting information regarding signal characteristics of a calibration signal which are contained in a signal received by the communication antenna, calibration means for calibrating a communication antenna chain based on the detected signal characteristic information, and cancellation signal generating means for generating a cancellation signal corresponding to a calibration signal contained in the signal received by the communication antenna based on the calibration signal. The device also includes signal cancellation-by-subtraction means for subtracting the generated cancellation signal from the signal received by the communication antenna, and receive signal processing means for processing the received signal that is diminished by the cancellation signal.

Abstract: A peak limiter for use in a system for amplifying a multi-carrier signal receives a baseband signal of each carrier of the multi-carrier signal. The multi-carrier signal is computationally estimated to have carriers combined in an RF band, and obtains power information of the multi-carrier signal to limit an amplitude of the baseband signal based on the power information of the estimated multi-carrier signal to thereby provide peak-limited baseband signals. Thus, the distortion generated by performing the unnecessary peak limitation can be effectively prevented to thereby improve the reliability of the entire system.

Abstract: To provide an amplifying device with reduced size, weight and cost. The amplifying device delays input signals using digital delay sections in a main signal system, performs offset rotation processing of digital input signals in carrier offset sections and power detection in a power detecting section in a control system, matches phases of a multi-carrier signal of the main signal system and a power value signal of the control system in a phase control section, and gives distortion compensation in a predistorter for canceling a nonlinear characteristic generated in an amplifier.

Abstract: A memory effect distortion component compensating unit compensates for a distortion component caused by the memory effect of the amplifier by using a time difference of results from raising an input signal to even power.

Abstract: A transmitter that effectively suppresses the peak level of transmit signals is equipped with peak reduction signal generating means that generates a peak reduction signal having a level based on a transmit signal level threshold for determining a peak of the transmit signal and on a transmit signal peak level and having a phase based on the phase of the transmit signal, peak reduction signal processing means that subjects the peak reduction signal to band restriction and orthogonal modulation, and transmit signal level suppressing means that subtracts the peak reduction signal subjected to band restriction and orthogonal modulation from the transmit signal.

Abstract: A distortion compensator that compensates for distortion arising in a main amplifier 10 that amplifies a signal effectively compensates for third order distortion which is unbalanced between the higher frequency band and lower frequency band. An amplitude detector 3 detects the level of a signal subject to amplification and a signal level change direction detection means 7 detects the direction of change in the level of the signal. A signal level change control means 4-8 stores the correspondence between the signal level and the mode of changing the signal in order to compensate for distortion for when the direction of change in the signal level is positive and when it is negative, and controls a signal change means 9 so that the amplitude and phase of the signal is changed in a mode of changing the signal corresponding to the detected direction of change in the signal level and the detected signal level.

Abstract: A CDMA mobile station apparatus receives a spread control signal including a non-orthogonal spread signal generated using a non-orthogonal spreading code which is non-orthogonal with a data signal spreading code and a spread data signal produced by spreading a data signal with a data signal spreading code from a base station apparatus via a radio link. The mobile station apparatus has a non-orthogonal spread signal generating unit for generating a non-orthogonal spread signal whose phase rotation caused by a radio transmission path is compensated for using a non-orthogonal spreading code, a subtracting unit for subtracting the generated non-orthogonal spread signal from the received signal to generate a difference signal, and a data signal demodulating unit for demodulating the difference signal into a data signal. The mobile station apparatus is capable of canceling an entire spread broadcasting signal, processing a band-limited signal, or processing a spreading code with a suppression coefficient.

Abstract: A base station for a mobile telephone system adopting a code division multiple access method comprising: a first delay profile measuring unit for receiving a random access channel signal, which is input to the base station for setting up a call, detecting at least one peak of the random access channel signal, and detecting the time of receiving the peak of the random access channel signal; and a data channel demodulator which despreads a data channel signal of the call set up by the random access channel signal, based on the peak receiving time of the random access channel signal detected by the first delay profile measuring unit.

Abstract: There is disclosed a synchronous circuit and a receiver in which a long code for use in communication can be determined in a short time, and circuit scale can be reduced. Upon receiving input of a data stop signal from a control unit, a matched filter continues to hold the signal held at the time, performs a product sum operation of a spreading code successively inputted from a spreading code generator and the held signal, and successively outputs correlation signals in the synchronous circuit and the receiver.

Abstract: A distortion compensator that compensates for distortion arising in a main amplifier 10 that amplifies a signal effectively compensates for third order distortion which is unbalanced between the higher frequency band and lower frequency band. An amplitude detector 3 detects the level of a signal subject to amplification and a signal level change direction detection means 7 detects the direction of change in the level of the signal. A signal level change control means 4-8 stores the correspondence between the signal level and the mode of changing the signal in order to compensate for distortion for when the direction of change in the signal level is positive and when it is negative, and controls a signal change means 9 so that the amplitude and phase of the signal is changed in a mode of changing the signal corresponding to the detected direction of change in the signal level and the detected signal level.

Abstract: A distortion compensation apparatus for compensating for the distortion occurring in an amplifier with high precision is provided. Distortion generating devices generate a distortion of amplitude or phase on a signal to be provided for an amplifier. A signal level detecting device detects a level of the signal provided for the amplifier, and a distortion amount control system controls the amount of distortion generated by the distortion generating devices on the basis of the level detected by the signal level detecting device, and at this time, a control timing adjusting system adjusts the timing for controlling the distortion amount by a distortion amount control system (D/A converters) so that the distortion occurring in the amplifier maybe compensated sufficiently.

Abstract: A despreading circuit which can reduce a circuit scale and power consumption is described. The circuit includes an A/D converter which converts a CDMA modulated analog signal to a digital signal of N bits, and a searcher which defects a synchronization phase from high-order small bits of the N bits and outputs synchronozation phase information to a control circuit. The control circuit transmits a signal for allowing despreading to be performed to a sliding correlator based on the phase information. The sliding correlator despreads the N bit digital signal outputted by the A/D converter and outputs the resulting correlation output as a despreading signal.

Abstract: There is disclosed a correlating operation method and a matched filter in which sensitivities in received code sequence selection and path detection are held to some degrees while circuit scale can be reduced. In the correlating operation method and the matched filter, code data obtained by adding or subtracting an in-phase component and a quadrature component of a received code sequence in a code mapping unit, and an in-phase component and a quadrature component of a received complex signal are subjected to correlating operation, and a correlating operation result is subjected to power adding operation to obtain a correlating operation output.

Abstract: To provide an amplifying device which is reduced in size, weight and cost and which can improve the distortion compensation performance. In the amplifying device, input signals are each subjected to digital orthogonal modulation using an IF and further to offset rotation processing in digital orthogonal modulators, then bifurcated into a main signal system and a control system, and detection of a power value is performed at an IF band in a power detecting section of the control system. Therefore, offset rotation processing of the input signals in the power detection is not required, so that a structure for matching phases of a multi-carrier signal and a power value signal is not required, resulting in improving the distortion compensation performance without using an analog delay line.