Algorithm for computing distances to a received point in an ADSL system
AssigneeTexas Instruments Incorporated
InventorsUdayan Dasgupta, Fernando A. Mujica, Murtaza Ali
Life of this patent
Estimating the term…
Abstract
Method for computing distances to received data points. A preferred embodiment comprises determining a first point on a grid nearest to the received point, computing a second point closest to the received point inside a specified area, wherein the second point is a point in a first coset, computing a third, fourth, and fifth point, wherein each point is a member of a different coset and each point is the closest point in its coset to the received point, and computing a distance from the received point to each of the second, third, fourth, and fifth points.
Claims22
A method for computing distances between a received point for a tone received in a receiver and four points in a two-dimensional grid with a constellation representing a number of bits greater than three, the method comprising:
- determining a first point on a grid nearest to the received point;
- computing a second point closest to the received point inside a specified area after determining the first point;
- computing a third, a fourth, and a fifth point, after computing the second point, wherein each of the second, the third, the fourth and the fifth points is a member of a different coset in the constellation and is the closest point in its coset to the received point;
- and
- computing distances from the received point to each of the second, the third, the fourth, and the fifth points;
- and
- providing the computed distances to a decoder.
A method for computing distances between a received point for a tone received in a receiver and a plurality of coset points in a two-dimensional grid with a constellation representing a number of bits greater than three, the method comprising:
- determining a received grid point on a grid nearest to the received point;
- determining whether the received grid point is valid;
- determining an alternate grid point inside a specified area if the received grid point is determined to be not valid;
- assigning the received grid point to a first coset point of the plurality of coset points if the received grid point is valid;
- assigning the alternate grid point to the first coset point of the plurality of coset points if the received grid point is not valid;
- computing remaining coset points of the plurality of coset points within the specified area, wherein each coset point is a member of a unique coset and is the closest point in its coset to the received point;
- computing distances from the received point to each coset point of the plurality of coset points;
- and
- providing the computed distances to a decoder.
Dependencies are inferred from the claim text.