Method and apparatus for selecting a spreading code in a spectrum spread communication system

A method of selecting one of a plurality of spreading codes with which to spread digital information in a spread spectrum transmitter, the method comprising the steps of:

• encoding a plurality of data bits to be transmitted to produce a plurality of encoded data bits;
• capturing a block of at least two encoded data bits of the plurality of encoded data bits;
• and
• selecting a spreading code from the plurality of spreading codes based on the block of at least two encoded data bits.

A spread spectrum transmitter comprising:

• means for selecting a plurality of data bits from digital information to be transmitted;
• means, coupled to the means for selecting the plurality of data bits, for capturing a block of at least two data bits of the plurality of data bits;
• and
• means, coupled to the means for capturing, for selecting a spreading code from a plurality of spreading codes based on the block of at least two data bits.

A spread spectrum transmitter comprising:

• an encoder for encoding a plurality of bits to be transmitted;
• a shift register, coupled to the encoder, for selecting at least two bits of the plurality of bits;
• and
• a multiplexer, coupled to the shift register, for selecting a spreading code from a plurality of spreading codes based on the at least two bits.

A spread spectrum receiver comprising:

• first means for correlating a first spreading code of a plurality of spreading codes with a received spread spectrum signal that includes a plurality of transmitted bits to produce a first correlated signal;
• second means for correlating a second spreading code of the plurality of spreading codes with the received spread spectrum signal to produce a second correlated signal;
• means, coupled to the first means for correlating and the second means for correlating, for determining a magnitude of the first correlated signal and a magnitude of the second correlated signal;
• means, coupled to the means for determining, for selecting the first spreading code when the magnitude of the first correlated signal exceeds the magnitude of the second correlated signal and for selecting the second spreading code when the magnitude of the second correlated signal exceeds the magnitude of the first correlated signal to produce a selected spreading code;
• means, coupled to the means for selecting, for identifying the plurality of transmitted bits based on the selected spreading code.

A method for selecting a spreading code from a plurality of spreading codes with which to identify a plurality of transmitted bits contained in a received spread spectrum signal, the method comprising the steps of:

• correlating the received spread spectrum signal with a first spreading code of the plurality of spreading codes to produce a first correlated signal;
• correlating the received spread spectrum signal with a second spreading code of the plurality of spreading codes to produce a second correlated signal;
• determining a magnitude of the first correlated signal and a magnitude of the second correlated signal;
• and
• selecting either the first spreading code or the second spreading code based on the magnitude of the first correlated signal and the magnitude of the second correlated signal.