Code multiplexing transmitting apparatus

A code multiplexing transmitting apparatus for spread-spectrum modulating transmission data of respective channels by spreading codes that differ from one another, combining the spread-spectrum modulated signals of each of the channels and transmitting the resultant spread-spectrum modulated signal, comprising:

• spread-spectrum modulating units each provided for each channel for outputting a respective spread-spectrum modulated signal;
• multiplexers for respectively multiplexing in-phase components and quadrature components of the spread-spectrum modulated signals of each channel outputted by the spread-spectrum modulating units;
• a quadrature modulator for quadrature modulating the code-multiplexed signals of the in-phase and quadrature components;
• and
• a transmitter for transmitting the signal modulated by said quadrature modulator;
• each of said spread-spectrum modulating units including:
• means for forming frames by forming transmission data into blocks every prescribed number of bits and inserting pilot signals at the beginning and end of each block;
• means for alternately distributing, one bit at a time, the frame signals to thereby convert in-phase component data and quadrature component data;
• means for respectively spread-spectrum modulating the in-phase component data and quadrature component data by spreading codes;
• and
• phase shifting means for shifting a phase of a signal-point position vector in an I (in phase), Q (quadrature) rectangular coordinate system of the spread-spectrum modulated signal by a prescribed angle.

A code multiplexing transmitting apparatus for spread-spectrum modulating transmission data of respective channels, comprising:

• a unit for providing spreading codes that differ from one another,
• a unit for modulating said transmission data with said spreading codes,
• a phase shifter for shifting phase of a signal-point position vector of the spread-spectrum modulated signal of each channel by a predetermined angle channel by channel such that phases of pilot signal portions of the spread-spectrum modulated signals of the respective channels are shifted relative to one another so that peak values of the code-multiplexed signal can be suppressed,
• a unit for combining said spread-spectrum modulated signals of each of said channels, and
• a unit for transmitting a resultant spread-spectrum modulated signal.