Data detection for codes with non-uniform spreading factors

Abstract

A plurality of communication signals is received. Each communication signal has an associated code. At least two of the communication signals have a different spreading factor. The associated codes have a scrambling code period. A total system response matrix has blocks. Each block has one dimension of a length M and another dimension of a length based on in part M and the spreading factor of each communication. M is based on the scrambling code period. Data of the received plurality of communication signals is received using the constructed system response matrix.

1 . A method for use in a wireless communication apparatus, the method comprising:
 receiving a plurality of communication signals that include an associated code, wherein at least one of the plurality of communication signals has a different spreading factor from another of the plurality of communication signals and wherein the associated code includes a scrambling code period;   constructing a total system response matrix having blocks, each block having one dimension of a length M and another dimension of a length based in part on M and the spreading factor of each communication signal, wherein M is based at least in part on the scrambling code period of each communication signal; and   using the constructed system response matrix to estimate data of the received plurality of communication signals.   
     
     
         2 . The method of  claim 1  wherein M is the scrambling code period. 
     
     
         3 . The method of  claim 1  wherein M is a multiple of the scrambling code period. 
     
     
         4 . The method of  claim 1  wherein the another dimension is a sum of dividing M by each communication's spreading factor. 
     
     
         5 . The method of  claim 1  further comprising constructing super columns, each super column having for each communication, a number of sequential columns from a system response matrix of that communication, the number of sequential columns being M divided by a spreading factor of that communication. 
     
     
         6 . The method of  claim 5  wherein each subsequent super column having non-zero elements one block lower in the matrix than a pervious column. 
     
     
         7 . The method of  claim 1  wherein the total system response matrix is A and the data estimating uses A H A in a zero forcing solution. 
     
     
         8 . The method of  claim 1  wherein the total system response matrix is A and the data estimating uses A H A+σ 2 I in a minimum mean square error solution, where σ 2  is the noise variance and I is an identity matrix. 
     
     
         9 . A wireless communication apparatus comprising:
 a receiver configured to receive a plurality of communication signals that include an associated code, wherein at least one of the plurality of communication signals has a different spreading factor from another of the plurality of communication signals and wherein the associated code includes a scrambling code period; and   a processor configured to construct a total system response matrix having blocks, each block having one dimension of a length M and another dimension of a length based in part on M and the spreading factor of each communication signal, wherein M is based at least in part on the scrambling code period of each communication signal;   wherein the wireless communication apparatus is configured to use the constructed system response matrix to estimate data of the received plurality of communication signals.   
     
     
         10 . The wireless communication apparatus of  claim 9  wherein M is the scrambling code period. 
     
     
         11 . The wireless communication apparatus of  claim 9  wherein M is a multiple of the scrambling code period. 
     
     
         12 . The wireless communication apparatus of  claim 9  wherein the another dimension is a sum of dividing M by each communication's spreading factor. 
     
     
         13 . The wireless communication apparatus of  claim 9  further comprising means for constructing super columns, each super column having for each communication, a number of sequential columns from a system response matrix of that communication, the number of sequential columns being M divided by a spreading factor of that communication. 
     
     
         14 . The wireless communication apparatus of  claim 13  wherein each subsequent super column having non-zero elements one block lower in the matrix than a pervious column. 
     
     
         15 . The wireless communication apparatus of  claim 9  wherein the total system response matrix is A and the data estimating uses AHA in a zero forcing solution. 
     
     
         16 . The wireless communication apparatus of  claim 9  wherein the total system response matrix is A and the data estimating uses A H A+σ 2 I in a minimum mean square error solution, where σ 2  is the noise variance and I is an identity matrix.