MC-CDMA multiplexing in an orthogonal uplink

An apparatus for wireless multi-carrier communications, comprising:

• means for dividing sub-carriers on an uplink into non-overlapping groups;
• means for allocating at least one time-frequency block, each time-frequency block having a hopping duration and a non-overlapped group;
• means for assigning a different set of orthogonal codes to each user;
• means for spreading symbols of each user over the allocated at least one time-frequency block, wherein the symbols of each user are spread using the different set of orthogonal codes assigned to each user;
• means for mapping each spread symbol to a modulation symbol in the at least one time-frequency block;
• means for generating an orthogonal waveform based on the mapped symbols;
• and
• means for transmitting the orthogonal waveform.

An apparatus for wireless multi-carrier communications, comprising:

• a controller operative to:
• divide sub-carriers on an uplink into non-overlapping groups,
• allocate at least one time-frequency block, each time-frequency block having a hopping duration and a non-overlapped group;
• and
• assign a different set of orthogonal codes to each user;
• a processor operative to:
• spread symbols of each user over the allocated at least one time-frequency block, wherein the symbols of each user are spread using the different set of orthogonal codes assigned to each user;
• and
• map each symbol to a modulation symbol in the at least one time-frequency block;
• and
• a transmitter operative to:
• generate an orthogonal waveform based on the mapped symbols;
• and
• transmit the orthogonal waveform.

A receiver in a wireless multi-carrier communications system, comprising:

• an antenna for receiving an orthogonal waveform;
• a demodulator for demodulating the orthogonal waveform, thereby creating spread symbols;
• a processor for determining a time-frequency block from the spread symbols;
• and
• a de-spreader for de-spreading the spread symbols in the time-frequency block using an orthogonal code for a user.

A readable media embodying a method for wireless multi-carrier communications, the method comprising:

• dividing sub-carriers on an uplink into non-overlapping groups;
• allocating at least one time-frequency block, each time-frequency block having a hopping duration and a non-overlapped group;
• assigning a different set of orthogonal codes to each user;
• spreading symbols of each user over the allocated at least one time-frequency block, wherein the symbols of each user are spread using the different set of orthogonal codes assigned to each user;
• mapping each spread symbol to a modulation symbol in the at least one time-frequency block;
• generating an orthogonal waveform based on the mapped symbols;
• and
• transmitting the orthogonal waveform.