Claims
- 1. An apparatus in an OFDM-CDMA communications system comprising:
a preprocessor receiving a plurality of signals and operative to produce an observation vector in response to said received signals; a postprocessor coupled to the preprocessor for linearly deriving at least one of a plurality of synchronization parameters in response to said observation vector; and a programmable multiuser detector producing a plurality of output signals in response to said linearly derived synchronization parameters.
- 2. The apparatus of claim 1 further comprising a selection control for selectively configuring the communications system to operate as one selected from the group consisting of Multi-Carrier CDMA, Multi-Carrier Direct Sequence CDMA, and Multi-Tone CDMA.
- 3. The apparatus of claim 1 wherein each of said synchronization parameters further comprises one selected from the group consisting of timing parameters, amplitude parameters, and carrier phase parameters associated with said received signals.
- 4. The apparatus of claim 1 wherein the preprocessor further comprises a RAKE receiver.
- 5. The apparatus of claim 4 wherein said RAKE receiver further comprises:
a synchronous circuit operative to receive the plurality of received signals; a plurality of delay elements for delaying a plurality of signals output from said synchronous circuits; a plurality of fingers operative to receive said delayed signals; a channel estimation block outputting an estimate; and a detector responsive to a plurality of signals output from said fingers and said output estimate from said channel estimation block to produce a plurality of raked output signals.
- 6. The apparatus of claim 1 wherein the preprocessor further comprises an update algorithm for obtaining results of Discrete Fourier Transform (DFT) for said synchronization parameters.
- 7. The apparatus of claim 1 wherein the postprocessor further comprises a linear estimator.
- 8. The apparatus of claim 7 wherein said linear estimator is one selected from the group consisting of a linear minimum mean square error (LMMSE) estimator and best linear unbiased estimator (BLUE).
- 9. A synchronization method in an OFDM-CDMA communications system comprising the steps of:
receiving a plurality of signals; producing an observation vector in response said received signals; linearly deriving at least one of a plurality of synchronization parameters in response to said observation vector; and detecting a plurality of output signals in response to said linearly derived synchronization parameters.
- 10. The method of claim 9 further comprising the step of selectively configuring the communications system to operate as one selected from the group consisting of Multi-Carrier CDMA, Multi-Carrier Direct Sequence CDMA, and Multi-Tone CDMA.
- 11. The method of claim 9 wherein each of said synchronization parameters further comprises one selected from the group consisting of timing parameters, amplitude parameters, and carrier phase parameters associated with said received signals.
- 12. The method of claim 9 further providing a RAKE receiver for producing said observation vector.
- 13. The method of claim 12 further comprising the steps of:
providing a synchronous circuit operative to receive the plurality of received signals; delaying a plurality of signals output from said synchronous circuits; providing a plurality of fingers operative to receive said delayed signals; providing a channel estimation block outputting an estimate; and producing a plurality of raked signals in response to a plurality of signals output from said fingers and said output estimate from said channel estimation block.
- 14. The method of claim 9 wherein the producing step further comprises the step of calculating results of Discrete Fourier Transform (DFT) of said parameters.
- 15. A synchronizer in an OFDM-CDMA communications system comprising:
a receiver operative to process a plurality of OFDM-CDMA signals; a database operative to store and provide a plurality of correlation matrixes; and a linearly programmable estimator coupled to said database operative to produce at least one of a plurality of synchronization parameters in response to said processed OFDM-CDMA signals.
- 16. The synchronizer of claim 15 wherein said estimator is one selected from the group consisting of a linear minimum mean square error (LMMSE) estimator and a best linear unbiased estimator (BLUE).
- 17. The synchronizer of claim 15 wherein each of said synchronization parameters further comprises one selected from the group consisting of timing parameters, amplitude parameters, and carrier phase parameters associated with said OFDM-CDMA signals.
- 18. An OFDM-CDMA communications system for deriving a plurality output signals from a plurality of received OFDM-CDMA signals, the system comprising:
means for deriving an observation vector during a training interval in response to said received OFDM-CDMA signals; means for linearly deriving at least one of a plurality of synchronization parameters in response to said observation vector during said training interval; and means for producing a plurality of output signals corresponding to said received OFDM-CDMA signals after said training interval in response to said synchronization parameters and said observation vector.
- 19. The system of claim 18 wherein each of said synchronization parameters further comprises one selected from the group consisting of timing parameters, amplitude parameters, and carrier phase parameters associated with said OFDM-CDMA signals.
- 20. The system of claim 18 further comprising means for selectively configuring said system to operate as one selected from the group consisting of Multi-Carrier CDMA, Multi-Carrier Direct Sequence CDMA, and Multi-Tone CDMA.
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present patent application relates to, and claims the priority of, U.S. Provisional Patent Application Serial No. 60/284,437 filed on Apr. 18, 2001, having common inventorship as the present application.
Provisional Applications (1)
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Number |
Date |
Country |
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60284437 |
Apr 2001 |
US |