Abstract: An interpolation method selection processing section 41 derives, from a ZF output signal, an error in a frequency direction and an error in a time direction concerning two transmit antennas (TxAnt#0#1) used in two antenna transmission, respectively, and determines if the error in the frequency direction is smaller than the error in the time direction. In case the determination indicates that the error in the frequency direction is smaller than the error in the time direction concerning the two transmit antennas (TxAnt#0#1), a frequency interpolation processing section 43 interpolates the ZF output signal in the frequency direction and produces a provisional estimate. If it is determined that the error in the frequency direction is not smaller than the error in the time direction concerning the two transmit antennas (TxAnt#0#1), a time interpolation processing section 42 interpolates the ZF output signal in the time direction and generates a provisional estimate.

Abstract: An interpolation method selection processing section 41 derives, from a ZF output signal, an error in a frequency direction and an error in a time direction concerning two transmit antennas (TxAnt#0#1) used in two antenna transmission, respectively, and determines if the error in the frequency direction is smaller than the error in the time direction. In case the determination indicates that the error in the frequency direction is smaller than the error in the time direction concerning the two transmit antennas (TxAnt#0#1), a frequency interpolation processing section 43 interpolates the ZF output signal in the frequency direction and produces a provisional estimate. If it is determined that the error in the frequency direction is not smaller than the error in the time direction concerning the two transmit antennas (TxAnt#0#1), a time interpolation processing section 42 interpolates the ZF output signal in the time direction and generates a provisional estimate.

Abstract: A cellular system in accordance with the present invention includes at least two base stations, a mobile station making communication with the base stations in multi-code CDMA, and an host station controlling communication made between the base stations and the mobile station. When one of the base stations becomes saturated, the mobile station makes communication in multi-code CDMA through a channel of other base station(s).

Abstract: A frequency control method in a CDMA communication system is described that prevents deterioration in communication quality even in cases in which a mobile station loses control of transmission power. A mobile station is determined to have failed when the difference between the reception Eb/I0 and a reference Eb/I0 exceeds a large predetermined value, whereupon the base station instructs the mobile station to turn off its power supply. If the power supply of that mobile station cannot be confirmed to be off, the base station instructs the mobile station to change its frequency. If the frequency change of that mobile station cannot be confirmed, the base station instructs normal mobile stations other than the failed mobile station to change frequency.

Abstract: In a transmit power control system according to the present invention, a reception level measuring unit measures a reception level based on pilot signals sent from a base station to a mobile station and a fading pitch measuring unit measures a fading pitch. A reference value control unit assigns a weight to the reception level with the fading pitch and sets an outer loop initial value of transmit power control based on the weighted reception level and information on required quality specified by the base station when an individual channel is set.

Abstract: A frequency control method in a CDMA communication system is described that prevents deterioration in communication quality even in cases in which a mobile station loses control of transmission power. A mobile station is determined to have failed when the difference between the reception Eb/I0 and a reference Eb/I0 exceeds a large predetermined value, whereupon the base station instructs the mobile station to turn off its power supply. If the power supply of that mobile station cannot be confirmed to be off, the base station instructs the mobile station to change its frequency. If the frequency change of that mobile station cannot be confirmed, the base station instructs normal mobile stations other than the failed mobile station to change frequency.

Abstract: A frequency control method in a CDMA communication system is described that prevents deterioration in communication quality even in cases in which a mobile station loses control of transmission power. A mobile station is determined to have failed when the difference between the reception Eb/I0 and a reference Eb/I0 exceeds a large predetermined value, whereupon the base station instructs the mobile station to turn off its power supply. If the power supply of that mobile station cannot be confirmed to be off, the base station instructs the mobile station to change its frequency. If the frequency change of that mobile station cannot be confirmed, the base station instructs normal mobile stations other than the failed mobile station to change frequency.

Abstract: In a CDMA cellular network where base stations share a common frequency and a first base station has a second frequency in addition to the common frequency, a mobile station receives a pilot signal from the first base station over the second frequency when it has established a connection to it, and transmits a first handoff request when the field strength of the pilot signal drops below a predefined threshold. In response, the first base station returns a change-frequencies command to the mobile station to cause it to switch to the common frequency and receive pilot signals from more than one base station over the common frequency. The mobile station transmits a second handoff request message containing a list of field strengths of the pilot signals. In response, the first base station makes a search through the list of field strengths and returns a handoff command to the mobile station and a connection setup command to a control station if a second base station appropriate for handoff is found.