Method and arrangement for use in a single user detector for a CDMA multi-path system
View Patent ↗A method and arrangement for use in a single user detector in a CDMA multi-path system, comprising providing a finite impulse response (FIR) filter; and configuring the FIR filter to derive at least a first, then a second, then a third, then a fourth of the following parameters for single user detection: R (auto-correlation) function; L (Cholesky decomposition) value; X value representative of the complex conjugate of a channel impulse response multiplied and summed with time shifted versions of a received signal; back substitution value Y (function of R, X and L); and back substitution value S (function of R, X, Y and L).
1. A method for utilizing a single configurable finite impulse response (FIR) filter for use in a single user detector in a code division multiple access (CDMA) multi-path system, comprising:
providing a single finite impulse response (FIR) filter;
configuring the FIR filter to derive at least a first, then a second, then a third, then a fourth of the following parameters for single user detection:
auto correlation function R,
X value representative of the complex conjugate of a channel impulse response multiplied and summed with time shifted versions of a received signal,
back substitution value Y determined from a first set of linear equations, wherein the back substitution value Y is a function of the auto correlation function R, the X value, and a Cholesky decomposition value L, and
back substitution value S determined from a second set of linear equations, wherein the back substitution value S is a function of the auto correlation function R, the X value, the back substitution value Y, and the L value; and
using the auto correlation function R, the X value, the back substitution value Y, and the back substitution value S in the single user detector to recover single user data transmitted from a transmitter.
2. The method of claim 1 , further comprising configuring the FIR filter to derive the Cholesky decomposition value L for single user detection.
3. The method of claim 1 , wherein the step of configuring the FIR filter comprises configuring the filter coefficients and the connection paths of summation elements in a plurality of stages of the FIR filter.
4. The method of claim 3 , wherein the step of configuring the connection paths of summation elements in a plurality at stages of the FIR filter comprises selecting connection paths from summation elements' outputs respectively to summation elements' input in adjacent stages.
5. The method of claim 4 , further comprising configuring the FIR filter to derive a Cholesky decomposition value L for single user detection, and wherein the step of configuring the connection paths of summation elements in a plurality of stages of the FIR filter comprises selecting feedback paths between output and input of the summation element within each stage.
6. The method of claim 1 wherein the FIR filter is in user equipment for use in a universal mobile telecommunications system (UMTS) system.
7. The method of claim 1 wherein the FIR filter is in a base station for use in a universal mobile telecommunications system (UMTS) system.
8. An arrangement for utilizing a single configurable finite impulse response (FIR) filter for use in a single user detector in a code division multiple access (CDMA) multi-path system, comprising:
a single finite impulse response (FIR) filter;
means for configuring the FIR filter to derive at least a first, then a second, then a third, then a fourth of the following parameters for single user detection:
auto correlation function R,
X value representative of the complex conjugate of a channel impulse response multiplied and summed with time shifted versions of a received signal,
back substitution value Y determined from a first set or linear equations, wherein the back substitution value Y is a function of the auto correlation function R, the X value, and a Cholesky decomposition value L, and
back substitution value S determined from a second set of linear equations, wherein the back substitution value S is a function of the auto correlation function R, the X value, the back substitution value Y, and the L value; and
means for using the auto correlation function R, the X value, the back substitution value Y, and the back substitution value S to recover single user data transmitted from a transmitter.
9. The arrangement of claim 8 , further comprising means for configuring the FIR filter to derive the Cholesky decomposition value L for single user detection.
10. The arrangement of claim 8 , wherein the means for configuring the FIR filter comprises means for configuring the filter coefficients and the connection paths of summation elements in a plurality of stages of the FIR filter.
11. The arrangement of claim 10 , wherein the means for configuring the connection paths of summation elements in a plurality of stages of the FIR filter comprises means for selecting connection paths from summation elements' outputs respectively to summation elements' input in adjacent stages.
12. The arrangement of claim 11 , further comprising means for configuring the FIR filter to derive a Cholesky decomposition value (L) for single user detection, and wherein the means for configuring the connection paths of summation elements in a plurality of stages of the FIR filter comprises means for selecting feedback paths between output and input of the summation element within each stage.
13. An integrated circuit comprising the arrangement of claim 8 .
14. A single user detector for use in a CDMA multi-path system, the single user detector comprising the arrangement of claim 8 .
15. User equipment for use in a universal mobile telecommunications system (UMTS) system, the user equipment comprising the arrangement of claim 8 .
16. A base station for use in a universal mobile telecommunications system (UMTS) system, the base station comprising the arrangement of claim 8 .