Power and confidence ordered low complexity soft turbomud with voting system
First Claim
1. An advanced receiver apparatus for processing multiple received signals with interfering signals, comprising:
- an ordering unit for ordering users indices, wherein on a first iteration ordering is based on received signal power, and wherein on subsequent iterations ordering is based on confidence values;
a multi-user detector coupled to said ordering unit producing a plurality of surviving states;
a voting unit coupled to said multi-user detector for processing said surviving states and generating a set of soft estimates of channel symbols; and
a decoder section coupled to said voting unit and said multi-user detector, wherein said decoder section processes said soft estimates of channel symbols to produce a final output on a final iteration, and wherein said decoder produces said confidence values for intermediate iterations.
3 Assignments
0 Petitions
Accused Products
Abstract
A real-time multi-user detection (MUD) receiver processing simultaneous digitally modulated interferers and transmissions in the same frequency optimizing performance for heavily loaded and overloaded multiple access systems by implementing an iterative TurboMUD receiver using tree-pruning, including confidence ordering, power-ordering, and a voting procedure. On the first iteration, user indices are ordered according to received powers. On subsequent iterations, the voting system provides soft decisions or confidence values utilized as soft inputs to single-user decoders. Voting is computationally attractive and allows the bank of decoders to operate on soft values, improving performance and reducing the number of turboMUD iterations. The bank of soft output error correction decoders produces an improved set of soft decisions or confidence values corresponding to the channel bits transmitted by each interfering user. Confidence values from the bank of decoders are used to order user indices, allowing the tree pruned MUD detector to operate on the most reliable symbols first, improving the likelihood that pruning is correct. Subsequent confidence ordering and estimate refinement occurs until conditions are satisfied and iterative processing completed.
29 Citations
23 Claims
-
1. An advanced receiver apparatus for processing multiple received signals with interfering signals, comprising:
-
an ordering unit for ordering users indices, wherein on a first iteration ordering is based on received signal power, and wherein on subsequent iterations ordering is based on confidence values;
a multi-user detector coupled to said ordering unit producing a plurality of surviving states;
a voting unit coupled to said multi-user detector for processing said surviving states and generating a set of soft estimates of channel symbols; and
a decoder section coupled to said voting unit and said multi-user detector, wherein said decoder section processes said soft estimates of channel symbols to produce a final output on a final iteration, and wherein said decoder produces said confidence values for intermediate iterations. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. A method for processing receiver signals from multiple users, comprising the steps of:
-
processing said receiver signals in a front end to generate a digital stream of signal samples;
performing parameter estimation of said digital stream;
ordering of users, wherein said ordering is a power ordering of said digital stream on a first iteration, and confidence ordering on subsequent iterations;
detecting a plurality of survivors from a set of symbol streams for each user;
voting on said survivors to generate a set of a soft-valued outputs, one stream for each user;
decoding said soft-valued outputs to form a set of confidence values;
repeating said steps of confidence ordering, detecting, voting, and decoding until a final state is obtained; and
outputting data estimates corresponding to a set of data bits. - View Dependent Claims (11, 12, 13, 14, 15, 16, 18, 19, 20, 21, 22, 23)
-
-
17. A receiver system for processing signals from multiple users with interfering signals, comprising:
-
a front end unit for receiving and processing incoming receptions;
a parameter estimator unit coupled to said front end unit for processing said receptions;
a filter section coupled to said front end unit;
an ordering unit coupled to said parameter estimation unit for ordering users indices, wherein on a first iteration ordering is based on received signal power, and wherein on subsequent iterations ordering is based on confidence values;
a multi-user detector coupled to said ordering unit and said filter section producing a plurality of surviving states;
a voting unit coupled to said multi-user detector for processing said surviving states and generating a set of soft estimates of channel symbols; and
a decoder section coupled to said voting unit and said multi-user detector, wherein said decoder section processes said soft estimates of channel symbols to produce a final output on a final iteration, and wherein said decoder produces said confidence values for intermediate iterations.
-
Specification