Method and apparatus for receiving CDMA radio communication

A CDMA mobile station which performs a number of modes including a start-up mode for searching a control channel immediately after power of the mobile station is turned ON, a standby mode for awaiting a call while searching for a nearest one of base stations of corresponding cells neighboring a cell in which the mobile station currently resides, and a communication mode for performing communication through a communication channel, comprising:

• a plurality of receiving fingers each including:
• a code generator for generating a spreading code;
• a correlator for despreading, with said spreading code, a received signal received from a base station to produce a despread signal as a correlation output;
• and
• a detector for performing signal detection on said despread signal to produce a detection signal;
• a RAKE combiner for combining the detection signals from a plurality of the receiving fingers into a baseband data signal;
• and
• a cell-search controller for controlling the code generator of each of the receiving fingers to generate a spreading code with a timing designated by said cell-search controller based on the correlation result from the correlator, wherein said cell-search controller sets, in at least one of said start-up mode, said standby mode and said communication mode, the code generator of at least one of the receiving fingers spreading codes assigned to control channels of cells.

A CDMA mobile station which performs a number of modes including a start-up mode for searching a control channel immediately after power of the mobile station is turned ON, a standby mode for awaiting a call while searching for a nearest one of base stations of corresponding cells neighboring a cell in which the mobile station currently resides, and a communication mode for performing communication through a communication channel, comprising:

• a plurality of receiving fingers each including:
• a code generator for generating a spreading code;
• a correlator for despreading, with said spreading code a received signal received from a base station to produce a despread signal as a correlation output;
• and
• a detector for performing signal detection on said despread signal to produce a detection signal;
• RAKE combiner for combining the detection signals from a plurality of the receiving fingers into a baseband data signal;
• and
• a cell-search controller for controlling the code generator of each of the receiving fingers to generate a spreading code with a timing designated by said cell-search controller based on the correlation result from the correlator, wherein said cell-search controller sets, in at least one of said start-up mode, said standby mode and said communication mode, the code generator of at least one of the receiving fingers spreading codes assigned to control channels of cells;
• wherein in a communication mode said cell-search controller sets the code generator in at least one of said plurality of receiving fingers to generate a spreading code corresponding to a communication channel assigned to a cell in which said mobile station currently resides, and sets the code generators in the receiving fingers, other than said plurality of receiving fingers, to generate spreading codes corresponding to control channels assigned to the cells neighboring said cell in which said mobile station currently resides;
• and further wherein said cell-search controller controls, depending on output level of the despread signal produced during reception of a control channel, a number of the receiving fingers in which the code generators are set for cell search to generate spreading codes of control channels assigned to cells neighboring a cell in which the mobile station currently resides.

A CDMA mobile station which performs a number of modes including a start-up mode for searching a control channel immediately after power of the mobile station is turned ON, a standby mode for awaiting a call while searching for a nearest one of base stations of corresponding cells neighboring a cell in which the mobile station currently resides, and a communication mode for performing communication through a communication channel, comprising:

• a plurality of receiving fingers each including:
• a code generator for generating a spreading code;
• a correlator for despreading, with said spreading code, a received signal received from a base station to produce a despread signal as a correlation output;
• and
• a detector for performing signal detection on said despread signal to produce a detection signal;
• a RAKE combiner for combining the detection signals from a plurality of the receiving fingers into a baseband data signal;
• and
• a cell-search controller for controlling the code generator of each of the receiving fingers to generate a spreading code with a timing designated by said cell-search controller based on the correlation result from the correlator, wherein said cell-search controller sets, in at least one of said start-up mode, said standby mode and said communication mode, the code generator of at least one of the receiving fingers spreading codes assigned to control channels of cells;
• wherein in a communication mode said cell-search controller sets the code generator in at least one of said plurality of receiving fingers to generate a spreading code corresponding to a communication channel assigned to a cell in which said mobile station currently resides, and sets the code generators in the receiving fingers, other than said plurality of receiving fingers, to generate spreading codes corresponding to control channels assigned to the cells neighboring said cell in which said mobile station currently resides;
• and further wherein said cell-search controller controls, depending on variation in multi-paths detected as different timings of peak levels in the despread signal, the timing of spreading codes to be generated by the code generators for communication channels.

A CDMA mobile station which performs a number of modes including a start-up mode for searching a control channel immediately after power of the mobile station is turned ON, a standby mode for awaiting a call while searching for a nearest one of base stations of corresponding cells neighboring a cell in which the mobile station currently resides, and a communication mode for performing communication through a communication channel, comprising:

• a plurality of receiving fingers each including:
• a code generator for generating a spreading code;
• a correlator for despreading, with said spreading code, a received signal received from a base station to produce a despread signal as a correlation output;
• and
• a detector for performing signal detection on said despread signal to produce a detection signal;
• a RAKE combiner for combining the detection signals from a plurality of the receiving fingers into a baseband data signal;
• and
• a cell-search controller for controlling the code generator of each of the receiving fingers to generate a spreading code with a timing designated by said cell-search controller based on the correlation result from the correlator, wherein said cell-search controller sets, in at least one of said start-up mode, said standby mode and said communication mode, the code generator of at least one of the receiving fingers spreading codes assigned to control channels of cells;
• wherein in a communication mode said cell-search controller sets the code generator in at least one of said plurality of receiving fingers to generate a spreading code corresponding to a communication channel assigned to a cell in which said mobile station currently resides, and sets the code generators in the receiving fingers, other than said plurality of receiving fingers, to generate spreading codes corresponding to control channels assigned to the cells neighboring said cell in which said mobile station currently resides;
• and further wherein said cell-search controller selects a predetermined number of largest peak levels of the despread signal and controls the code generators of said predetermined number of the receiving fingers to generate spreading codes with the selected timing.