Back to results
US 6,633,615 B1Granted
Trellis transition-probability calculation with threshold normalization
AssigneeAgere Systems Inc.
InventorsSteven P. Pekarich, Xiao-An Wang
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
AssigneeAgere Systems Inc.
InventorsSteven P. Pekarich, Xiao-An Wang
Estimating the term…
A circuit performs threshold normalization of accumulated transition probabilities for a given state of a state transition trellis in a maximum likelihood detector. Threshold normalization may be accomplished by comparison and setting of a single bit in stored transition probabilities. Threshold value comparison may be accomplished by comparing the bth bit of the stored transition probabilities if the threshold value is 2b. When all transition probabilities exceed the threshold value at a stage of the trellis, the transition probabilities are scaled, such as by subtracting the threshold value. Scaling may be implemented by setting the compared bth bits to zero before storage. In general, since accumulated transition probabilities are monotonically increasing for transition probabilities of paths through the trellis in both forward and reverse directions, the present invention may be employed for both threshold normalization of both the forward (α) and reverse (β) transition probabilities.
For a signal processing application, a method of threshold normalization of a plurality of transition probabilities of a state transition trellis, each transition probability stored as a binary value of M bits, comprising the steps of:
For a signal processing application, a circuit for threshold normalization of a plurality of transition probabilities of a state transition trellis, each transition probability stored as a binary value of 2M bits, comprising:
A computer-readable medium having stored thereon a plurality of instructions, the plurality of instructions including instructions which, when executed by a processor, cause the processor to implement a method of threshold normalization of a plurality of transition probabilities of a state transition trellis, each transition probability stored as a binary value of M bits, the method comprising the steps of:
Dependencies are inferred from the claim text.