US 2011/0033009 A1Published application

System and Method for Adapting a Change in Constellation Density While Receiving a Signal

AssigneeParadyne Corporation

InventorWilliam L. Betts

Life of this patent

Estimating the term…

Loading patent…

Abstract

One embodiment comprises a transmitter precoder operating on an input signal to produce an output signal for modulation. The output signal is transmitted using a constellation with a constellation density. The transmitter precoder comprises scaler logic, precoder logic and selection logic. The scaler logic scales the input signal to maintain constant power on the input signal independent of the constellation density. The precoder logic precodes the scaled signal to produce a dither signal limited to a range of values. The range is inversely proportional to the constellation density. The selection logic is operable in two states. In the first state, the selection logic combines the scaled signal with the dither signal to produce the output signal. In the second state, the selection provides the scaled signal as the output signal.

Claims20

Dependent claims

A transmitter for transmitting a plurality of data bits as a stream of multi-dimensional Trellis symbols, each multi-dimensional Trellis symbol comprising a first Trellis symbol component and a second Trellis symbol component, each Trellis symbol component comprising a first portion and a second portion, each Trellis symbol component being transmitted during a symbol period, the transmitter comprising:

a constellation encoder configured to encode a first group of the data bits into a first portion of a Trellis symbol component, the first portion representing a subset-encoded constellation;
a mapper configured to produce a second portion of the Trellis symbol component, the second portion representing a signal point within the constellation, the mapper having a first and a second input, where the first input is the subset-encoded constellation, and the second input is selected from a second group of the data bits or a third group of the data bits;
a Trellis encoder configured to encode at least one of the bits in the third group;
an interleaver configured to select the second mapper input to alternate between the second group and the third group on alternate symbol periods, such that the first Trellis symbol component and the second Trellis symbol component of the multi-dimensional Trellis symbol are not sequential.

1 more element

Dependencies are inferred from the claim text.

Facts

Application: 12/908,325Filed 20 Oct 2010
Priority: 1 Oct 2003
Published: 10 Feb 2011
Term ends: Not estimatedThe source records don’t support an estimate.

Classification5 codes

H04L 1/0006
Systems modifying transmission characteristics according to link quality, e.g. power backoff: by adapting the transmission format
H04L 25/03343
Arrangements for removing intersymbol interference: arrangements at the transmitter end
H04L 27/3427
In which the information is carried by both the individual signal points and the subset to which the individual points belong, e.g. using coset…:…
H04L 2025/0342
Passband transmission: qam

Family

Application60/507,885Us provisional application · filed 1 Oct 2003
Application10/956,780Division · filed 1 Oct 2004
Application12/394,591Division · filed 27 Feb 2009
Application12/908,325Division
US 2005/0074070 A1Published application
US 2009/0161792 A1Published application
US 7,522,679 B2Related patent
US 7,835,459 B2Related patent
US 8,279,969 B2Related patent
US 2011/0033009 A1This patent

From the US filing history. Foreign family members aren’t listed.