Iterative multi-stage detection technique for a diversity receiver having multiple antenna elements

A system for separating K symbol streams, each of the K symbol streams being conveyed by K respective orthogonally spread channels in a receiver chain, the K channels including a first set of N channels and a second set of M channels, each of the N channels being spread according to a corresponding one of N orthogonal sequences and each of the M channels being spread according to one of the N orthogonal sequences, the system comprising:

• one or more circuits that despreads the first set of N channels so as to generate N separate channels;
• said one or more circuits detects, from the N separate channels, a set of N symbols wherein each of the N symbols is conveyed by a corresponding one of the N channels;
• said one or more circuits generates a first interference signal due to the first set of N channels based upon the set of N symbols;
• said one or more circuits subtracts the interference signal from the second set of M channels;
• said one or more circuits despreads the second set of M channels so as to generate M separate channels;
• said one or more circuits detects, from the M separate channels, a set of M symbols wherein each of the M symbols is conveyed by a corresponding one of the M channels;
• and
• said one or more circuits provides K separate symbols wherein the K separate symbols include the set of N symbols and the set of M symbols.

A system for separating K symbol streams, each of the K symbol streams being conveyed by K respective orthogonally spread channels in a receiver chain, the K channels including a first set of N channels and a second set of M channels, each of the N channels being spread according to a corresponding one of N orthogonal sequences and each of the M channels being spread according to one of the N orthogonal sequences, the system comprising:

• at least one processor that despreads the first set of N channels so as to generate N separate channels;
• said at least one processor detects, from the N separate channels, a set of N symbols wherein each of the N symbols is conveyed by a corresponding one of the N channels;
• said at least one processor generates a first interference signal due to the first set of N channels based upon the set of N symbols;
• said at least one processor subtracts the interference signal from the second set of M channels
• said at least one processor despreads the second set of M channels so as to generate M separate channels;
• said at least one processor detects, from the M separate channels, a set of M symbols wherein each of the M symbols is conveyed by a corresponding one of the M channels;
• and
• said at least one processor provides K separate symbols wherein the K separate symbols include the set of N symbols and the set of M symbols.