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For use in a CDMA receiver, a noise reduction circuit improves the signal-to-noise ratio of a received CDMA signal comprising a series of chip sequences. The noise reduction circuit comprises: 1) a sampling circuit for generating an original plurality of samples of the received signal; and 2) a cont

For use in a CDMA receiver, a noise reduction circuit improves the signal-to-noise ratio of a received CDMA signal comprising a series of chip sequences. The noise reduction circuit comprises: 1) a sampling circuit for generating an original plurality of samples of the received signal; and 2) a controller for determining a first plurality of time slots containing chip samples equal to Logic 1, and a second plurality of time slots containing chip samples equal to Logic 0. The controller generates a reconstructed plurality of samples by at least one of: a) modifying an order of a first Logic 1 chip sample and a second Logic 1 chip sample; and b) modifying an order of a first Logic 0 chip sample and a second Logic 0 chip sample.

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For use in a CDMA receiver, a noise reduction circuit improves the signal-to-noise ratio of a received CDMA signal comprising a series of chip sequences. The noise reduction circuit comprises: 1) a sampling circuit for generating an original plurality of samples of the received signal; and 2) a cont

For use in a CDMA receiver, a noise reduction circuit improves the signal-to-noise ratio of a received CDMA signal comprising a series of chip sequences. The noise reduction circuit comprises: 1) a sampling circuit for generating an original plurality of samples of the received signal; and 2) a controller for determining a first plurality of time slots containing chip samples equal to Logic 1, and a second plurality of time slots containing chip samples equal to Logic 0. The controller generates a reconstructed plurality of samples by at least one of: a) modifying an order of a first Logic 1 chip sample and a second Logic 1 chip sample; and b) modifying an order of a first Logic 0 chip sample and a second Logic 0 chip sample. values from said corresponding one of the fingers when an output of said combining unit is greater than or equal to a predetermined value. 6. The radio communication apparatus as claimed in claim 5, wherein said combining unit combines the maximum correlation value obtained after combining the fingers, at the predetermined ratio, on condition that said lock controller enables and locks the output of the correlation values from said corresponding one of the fingers. 7. The radio communication apparatus as claimed in claim 5, which further comprises: a code generator which generates an M-ary quadrature code corresponding to the maximum correlation value of said corresponding one of the fingers; and a comparator which compares the M-ary quadrature code generated by said code generator and an M-ary quadrature code corresponding to the maximum correlation value obtained after combining the fingers, said combining ,unit combining the maximum correlation value obtained after combining the fingers, at the predetermined ratio, on condition that the M-ary quadrature codes compared in said comparator match. 8. The radio communication apparatus as claimed in claim 7, which further comprises: a moving average unit which obtains a moving average of an output of said comparator indicating a match or no match, said combining unit combining the maximum correlation value obtained after combining the fingers, at the predetermined ratio, on condition that an output of said moving average unit is greater than or equal to a predetermined value. 9. The radio communication apparatus as claimed in claim 7, said combining unit combines the maximum correlation value obtained after combining the fingers, at the predetermined ratio, on condition that said lock controller enables and locks the output of the correlation values from said corresponding one of the fingers. 10. The radio communication apparatus as claimed in claim 5, wherein the correlation values are obtained by carrying out a QPSK modulation with respect to M-ary quadrature codes at a transmitting end, carrying out a QPSK demodulation at a receiving end, carrying out an Hadamard transform using an Mary quadrature code sequence with respect to demodulated signals I and Q to obtain correlation values (I1 through In) and (Q1 through Qn) of the codes, and finally obtaining sums of squares (I12+Qn2) through (In2+Qn2). 11. A radio communication apparatus which subjects each signal which is received via a multi-path and demodulated, to a Hadamad transform at each of fingers, by use of an M-ary quadrature coding scheme, obtains correlation values of codes, combines correlation values output from fingers which obtain valid correlation values, and demodulates a received signal based on a maximum correlation value of combined correlation values, said radio communication apparatus comprising: a maximum value detector which obtains a maximum correlation value of a corresponding one of the fingers; a code generator which generates an M-ary quadrature code corresponding to the maximum correlation value of said corresponding one of the fingers; a comparator which compares the M-ary quadrature code generated by said code generator and an M-ary quadrature code corresponding to the maximum correlation value obtained after combining the fingers; a selector which selects the maximum correlation value of said corresponding one of the fingers or a predetermined coefficient multiple thereof when no match is detected by said comparator, and selects the maximum correlation value obtained after combining the fingers or a predetermined coefficient multiple thereof when a match is detected by said comparator; and a lock controller which enables and locks output of the correlation values from said corresponding one of the fingers when an output of said selector is greater than or equal to a predetermined value. 12. The radio communication apparatus a cla imed in claim 11 which further comprises: a moving average unit which obtains a moving average of an output of said comparator indicating the match or no match, said selector selecting the maximum correlation value obtained after combining the fingers or the predetermined coefficient multiple thereof on condition that an output of said moving average unit is greater than or equal to a predetermined value. 13. The ratio communication apparatus as claimed in claim 11, said selector selecting the maximum correlation value obtained after combining the fingers or the predetermined coefficient multiple thereof on condition that said lock controller enables and locks the output of the correlation values from said corresponding one of the fingers. 14. The radio communication apparatus as claimed in claim 11, wherein the correlation values are obtained by carrying out a QPSK modulation with respect to M-ary quadrature codes at a transmitting end, carrying out a QPSK demodulation at a receiving end, carrying out an Hadamard transform using an M-ary quadrature code sequence with respect to demodulated signals I and Q to obtain correlation values (I1 through In) and (Q1 through Qn) of the codes, and finally obtaining sums of squares (I12+Qn2) through (In2+Qn2). 15. A radio communication apparatus which subjects each signal which is received via a multi-path and demodulated, to a Hadamard transform at each of fingers, by use of an M-ary quadrature coding scheme, obtains correlation values of codes, combines correlation values output from fingers which obtain valid correlation values, and demodulates a received signal based on a maximum correlation value of combined correlation values, said radio communication apparatus comprising a comparator which compares demodulated data for an arbitrary combination of 2 paths; and a lock controller which disables and unlocks output of the correlation values from corresponding one of the fingers based on a detection of a match or an approximate match in said comparator. 16. The radio communication apparatus as claimed in claim 15, wherein said comparator includes means for obtaining a correlation between 2 inputs. 17. The radio communication apparatus as claimed in claim 15, wherein the correlation values are obtained by carrying out a QPSK modulation with respect to M-ary quadrature codes at a transmitting end, carrying out a QPSK demodulation at a receiving end, carrying out an Hadamard transform using an M15 ary quadrature code sequence with respect to demodulated signals I and Q to obtain correlation values (I1 through In) and (Q1 through Qn) of the codes, and finally obtaining sums of squares (I12+Qn2) through (In2+Qn2). 18. A radio communication apparatus which subjects each signal which is received via a multi-path and demodulated, to a Hadamard transform at each of fingers, by use of an M-ary quadrature coding scheme, obtains correlation values of codes, combines correlation values output from fingers which obtain valid correlation values, and demodulates a received signal based on a maximum correlation value of combined correlation values, said radio communication apparatus comprising: a comparator which compares M-ary quadrature codes corresponding to maximum correlation values obtained for an arbitrary combination of 2 fingers; and a lock controller which disables and unlocks output of the correlation values from one of the 2 fingers when a match is detected by said comparator. 19. The radio communication apparatus as claimed in claim 18, wherein said comparator compares M-ary quadrature codes corresponding to the maximum correlation values and second largest correlation values obtained for the arbitrary combination of the 2 fingers. 20. The radio communication apparatus as claimed in claim 18, wherein said comparator includes means for obtaining a correlation between 2 inputs. 21. The rad