Code multiplexing transmitting apparatus

Claim 2

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, 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.

Claim 3

The apparatus according to claim 1, wherein said phase shifter shifts the phase of the signal point position vector of the spread-spectrum modulated signal of each channel by a predetermined angle only in a case where the spread-spectrum modulated signals of respective channels carries identical data at identical timings.

Claim 4

The apparatus according to claim 2, wherein said phase shifter makes an amount of phase shift θ of an ith channel equal to 360°·i/N, where N represents the number of channels.

Claim 5

The apparatus according to claim 2, wherein amounts of phase shift are brought into 1:1 correspondence with the spreading codes and said phase shifter obtains the amount of phase shift that conforms to a spreading code used in spread-spectrum modulation and rotates the phase of the signal-point position vector by the amount of this phase shift.

Claim 6

The apparatus according to claim 2, further comprising means for notifying a receiver side of an amount of phase shift of each channel by a control channel or by a special-purpose channel dedicated to giving notification of the amount of the phase shift.

Claim 7

The apparatus according to claim 2, further comprising: means for inserting data, which notifies a receiver side of the amount of phase shift, into the transmission data; and means for transmitting the data representing the amount of phase shift to the receiver side together with the transmission data.

Claim 8

The apparatus according to claim 1, wherein said phase shifter makes the prescribed angle equal to 0, π/2, π or 3π/2 in a case where QPSK spread-spectrum modulation is performed.

Claim 9

The apparatus according to claim 7, wherein (m·π/2) is adopted as the amount of phase shift of an ith channel, where m=mod(i,4) holds (where m is the remainder obtained when i is divided by 4).

Claim 10

The apparatus according to claim 8, wherein said phase shifter shifts the phase of a signal-point position vector of the spread-spectrum modulated signal of each channel by a prescribed angle only in a case where the spread-spectrum modulated signals of respective channels carries identical data at identical timings.

Claim 11

The apparatus according to claim 1, wherein said phase shifter determines the number of signal-points based upon the number of channels used.

Claim 12

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.

Claim 13

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.

Claim 14

The apparatus according to claim 11, wherein said phase shifter makes an amount of phase shift θ of an ith channel equal to 360°·i/N, where N represents the number of channels.

Claim 15

The apparatus according to claim 11, wherein (m·π/2) is adopted as the amount of phase shift θ of an ith channel, where m=mod(i,4) holds (where m is the remainder obtained when i is divided by 4).

Claim 16

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.

Claim 17

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.