Multiple channel interference cancellation
First Claim
1. A method for reducing interference in an incoming signal received at a transceiver of a multi-channel communication device comprising:
- receiving, in a serial format, a signal to be transmitted over a channel, the transmitted signal to be transmitted from the transceiver;
converting the signal to a parallel format;
performing overlap processing on the signal;
performing a Fourier transform on the signal to create a transform domain signal;
distributing the transform domain signal to two or more multipliers, at least one of which is associated with a different channel;
multiplying the transform domain signal by one or more weighting variables to create a weighted transform domain signal;
performing an inverse Fourier transform on the weighted transform domain signal to create a cancellation signal;
performing overlap processing on the cancellation signal;
converting the cancellation signal to a serial format; and
combining the cancellation signal with the incoming signal to reduce interference in the incoming signal.
3 Assignments
0 Petitions
Accused Products
Abstract
A method and apparatus for reducing crosstalk in a multi-channel communication system is disclosed. In one embodiment, outgoing signals in a multi-channel environment are manipulated into a transform domain, such as the frequency domain. Thereafter, the signals may be combined and modified based on a weighting variable to create a cancellation signal. Combined processing greatly reduces system complexity and increases processing speed. After processing in the transform domain, the cancellation signal undergoes further processing to return the cancellation signal into the time domain. The cancellation signal may then be combined with received signals to cancel crosstalk or echo. A method and apparatus for crosstalk cancellation in the analog domain and digital domain is also disclosed. Cancellation at least partially in the analog domain reduces the dynamic range requirements for digital to analog converters within the front-end processing system of a receiver and thereby reducing clipping and increasing operating speed.
-
Citations
47 Claims
-
1. A method for reducing interference in an incoming signal received at a transceiver of a multi-channel communication device comprising:
-
receiving, in a serial format, a signal to be transmitted over a channel, the transmitted signal to be transmitted from the transceiver;
converting the signal to a parallel format;
performing overlap processing on the signal;
performing a Fourier transform on the signal to create a transform domain signal;
distributing the transform domain signal to two or more multipliers, at least one of which is associated with a different channel;
multiplying the transform domain signal by one or more weighting variables to create a weighted transform domain signal;
performing an inverse Fourier transform on the weighted transform domain signal to create a cancellation signal;
performing overlap processing on the cancellation signal;
converting the cancellation signal to a serial format; and
combining the cancellation signal with the incoming signal to reduce interference in the incoming signal. - View Dependent Claims (2, 3, 4, 40, 41)
-
-
5. In a multi-channel environment, a method for canceling interference in one or more received signals comprising:
-
receiving two or more outgoing signals;
converting the two or more outgoing signal to a transform domain to create a transform domain signal for each channel;
distributing the transform domain signal for each channel to a multiplier associated with each channel;
processing, with the multiplier, the transform domain signal from each channel with weighting variables to generate two or more cancellation signals in the transform domain;
combining the two or more cancellation signals in the transform domain to create a combined transform domain cancellation signal;
converting the combined transform domain cancellation signal out of the transform domain to obtain a cancellation signal for each channel; and
combining the cancellation signal for each channel with the signal received on each the channel to cancel interference. - View Dependent Claims (6, 7, 8, 9, 10, 11)
-
-
12. A cancellation system for reducing interference in a received signal in a multi-channel communication device, wherein the cancellation system for each channel comprises:
an input for receiving an outgoing signal at a first transceiver, the outgoing signal in a first domain;
a transform unit configured to manipulate the outgoing signal into a second domain signal and distribute the second domain signal to at least one multiplier associated with each channel;
one or more a multipliers associated with each channel configured to receive the distributed second domain signal from each channel and multiply the second domain signal with one or more weighting variables to create a cancellation signal in the second domain;
an inverse transform unit configured to perform an inverse transform on the cancellation signals in the second domain to create a cancellation signal in the first domain; and
a subtractor configured to subtract the cancellation signal that is in the first domain from a received signal. - View Dependent Claims (13, 14, 15, 16, 17, 18)
-
19. A cancellation system for use in a multi-channel transceiver to cancel unwanted coupling comprising:
-
one or more inputs, wherein each input provides an outgoing signal to the cancellation system;
a transform unit associated with each channel, wherein each transform unit is configured to convert an outgoing signal from a channel to a transform domain;
one or more multipliers, wherein each multiplier is configured to receive the outgoing signal from each channel in the transform domain and multiply the outgoing signal from each channel in the transform domain with a weighting variable to create one or more cancellation signals in the transform domain;
one or more devices configured to combine two or more cancellation signals in the transform domain to create a combined cancellation signal in the transform domain for each channel; and
a inverse transform unit associated with each channel configured to receive the combined cancellation signal and reverse the processing of the transform units. - View Dependent Claims (20, 21, 22, 23, 24, 25)
-
-
26. A method for generating a cancellation signal in a cancellation system, wherein said method occurs within a multi-channel communication system comprising:
-
receiving at a cancellation system two or more signals, wherein the two or more signals relate to one or more outgoing signals on the two or more channels in the multi-channel communication system;
performing a single transform operation on each of the two or more signals to convert each of the two or more signals into a transform domain;
distributing the two or more signals in the transform domain to a multipliers associated with each of the channels;
multiplying the two or more signals in the transform domain by one or more weighting variables to create one or more multiplier outputs;
combining the one or more multiplier outputs associated with each channel to create a combined transform domain cancellation signal, wherein the transform domain cancellation signal is associated with a channel; and
performing a single inverse transform operation on each of the transform domain cancellation signals to remove the cancellation signal from the transform domain and thereby create the cancellation signal for each channel. - View Dependent Claims (27, 28, 29, 30, 31, 42)
-
-
32. A method of generating one or more weighting variables for use in a cancellation system comprising:
-
receiving one or more error signals, each of the one or more error signals associated with a channel in a multi-channel communication device;
receiving one or more data signals, the data signals in a transform domain and associated with a channel;
converting the one or more error signals to a transform domain;
performing adaptation processing on the one or more error signals in the transform domain and the one or more data signals in the transform domain to generate at least one weighting variables for each channel; and
outputting the weighting variable for each channel to a shared multiplier associated with each channel, wherein the weighting variable is configured to modify the data signals in a transform domain to generate a cancellation signal. - View Dependent Claims (33, 34, 43, 44, 45, 46, 47)
-
-
35. A system for generating a two or more weighting variables for use by a transform domain processing module in an interference cancellation system comprising:
-
a first input configured to receive two or more a feedback signals;
a second input configured to receive a two or more data signals;
a transform unit configured to receive either or both of the feedback signal and the data signal and transform either or both of the feedback signal and the data signal into a transform domain, wherein the transform unit is shared between two or more channels; and
an adaptation module configured to process the feedback signal and the data signal to generate one or more weighting variables, wherein the adaptation module is shared by two or more channels. - View Dependent Claims (36, 37, 38, 39)
-
Specification