Method and apparatus for modulating signal waveforms in a CDMA communication system

A spread spectrum communication system including a modulator for modulating a digital user information signal for transmission over a communication channel, said modulator comprising:

• orthogonal sequence generator means for receiving said user information signal and for generating, in accordance with a value of said user information signal, a preselected Walsh sequence included within a set of orthogonal Walsh binary sequences, each of said orthogonal binary chip sequences having a selected chip of an identical binary value located at an identical predefined sequence position;
• means for combining said preselected Walsh sequence signal with a control signal to generate a first punctured sequence signal, said punctured sequence signal including a control chip at said predefined sequence position having a binary value corresponding to said control signal;
• pseudorandom noise (PN) generator means for generating first and second PN signals of a code sequence different from one another;
• and
• combiner means for receiving and combining said punctured sequence signal respectively with said first and second PN signals, and providing resultant first and second output modulation signals.

A method for modulating a spread spectrum information signal, comprising the steps of:

• generating, in accordance with a value of said information signal, a first orthogonal sequence signal corresponding to a selected one of a plurality of orthogonal binary chip sequences, each of said orthogonal binary chip sequences having a selected chip of a common predefined binary value located at a common predefined sequence position;
• combining said first orthogonal sequence signal with a control signal to generate a first punctured sequence signal, said punctured sequence signal including a control chip at said predefined sequence position having a binary value corresponding to said control signal;
• generating a pseudo-noise (PN) signal corresponding to a predetermined PN binary sequence;
• and
• combining said first punctured sequence signal and said PN signal so as to provide a resultant first modulation signal.

A method for transmitting a digital user information signal over a communication channel, said method comprising the steps of:

• generating, in accordance with a value of said digital user information signal, a preselected Walsh sequence included within a set of orthogonal Walsh binary sequences, each of said orthogonal binary chip sequences having a selected chip of an identical binary value located at an identical predefined sequence position;
• combining said preselected Walsh sequence signal with a control signal to generate a first punctured sequence signal, said punctured sequence signal including a control chip at said predefined sequence position having a binary value corresponding to said control signal;
• means for generating first and second pseudorandom noise (PN) signals of a code sequence different from one another;
• and
• receiving and combining said first punctured sequence signal respectively with said first and second PN signals, and providing resultant first and second output modulation signals.

A digital communication system, comprising:

• means for receiving an input signal and for generating, in accordance with a value of said input signal, a first orthogonal sequence signal corresponding to one of a plurality of orthogonal binary chip sequences, each of said orthogonal binary chip sequences having a selected chip of an identical binary value located at an identical predefined sequence position;
• means for combining said first orthogonal sequence signal with a control signal to generate a first punctured sequence signal, said punctured sequence signal including a control chip at said predefined sequence position having a binary value corresponding to said control signal;
• and
• a transmitter for modulating a carrier signal using said punctured sequence signal, and for transmitting the resulting modulated carrier signal.

A method for communicating a digital information signal over a communication channel comprising the steps of:

• generating, in accordance with a value of said digital information signal, a first orthogonal sequence signal corresponding to a selected one of a plurality of orthogonal binary chip sequences, each of said orthogonal binary chip sequences having a selected chip of common binary value located at a common predefined sequence position;
• combining said first orthogonal sequence signal with a control signal to generate a first punctured sequence signal, said punctured sequence signal including a control chip at said predefined sequence position having a binary value corresponding to said control signal;
• and
• combining said first punctured sequence signal and a PN signal so as to provide a resultant first modulation signal.