Techniques for using discrete spectra

A wireless communication method, comprising:

• receiving a set of time-domain symbols carrying a set of processed data modulated on multiple subcarrier groups,
• wherein each subcarrier group comprises an even number of subcarriers and adjacent subcarrier groups are separated by unused subcarriers,
• wherein a number of the unused subcarriers is greater than or equal to a number of subcarriers in any of the adjacent subcarrier groups, and
• wherein the set of processed data corresponds to an output of:
• a first spreading code [1, −1] applied to data carried in subcarrier groups having 2×m subcarriers based on m being a positive odd number, and
• one or more spreading codes of length 2 or of length 4 applied to data carried in subcarrier groups having 2×n subcarriers based on n being a positive even number;
• and
• demodulating the set of time-domain symbols to obtain time domain data.

A communication apparatus, comprising a processor configured to implement a method, comprising:

• determine a set of time-domain symbols by an application of an inverse Fourier transform to a set of processed data modulated on multiple subcarrier groups,
• wherein each subcarrier group comprises an even number of subcarriers and adjacent subcarrier groups are separated by unused subcarriers,
• wherein a number of the unused subcarriers is greater than or equal to a number of subcarriers in any of the adjacent subcarrier groups, and
• wherein the set of processed data is determined by the processor configured to:
• apply a first spreading code [1, −1] to data carried in subcarrier groups having 2×m subcarriers based on a determination that m is a positive odd number, and
• apply one or more spreading codes of length 2 or of length 4 to data carried in subcarrier groups having 2×n subcarriers based on a determination that n is a positive even number;
• and
• transmit the set of time-domain symbols.

A communication apparatus, comprising a processor configured to implement a method, comprising:

• receive a set of time-domain symbols carrying a set of processed data modulated on multiple subcarrier groups,
• wherein each subcarrier group comprises an even number of subcarriers and adjacent subcarrier groups are separated by unused subcarriers,
• wherein a number of the unused subcarriers is greater than or equal to a number of subcarriers in any of the adjacent subcarrier groups, and
• wherein the set of processed data corresponds to an output of:
• a first spreading code [1, −1] applied to data carried in subcarrier groups having 2×m subcarriers based on m being a positive odd number, and
• one or more spreading codes of length 2 or of length 4 applied to data carried in subcarrier groups having 2×n subcarriers based on n being a positive even number;
• and
• demodulate the set of time-domain symbols to obtain time domain data.