Self interference cancellation for high performance transceivers

A system, comprising:

• a directional coupler configured to pass an upstream signal and receive a downstream signal on an upstream channel and a downstream channel that are adjacent;
• a transmit path that includes a digital transmitter component configured to transmit the upstream signal;
• a receive path that includes a first receiver component and a first subtraction component;
• a feedback path for processing a sampled echoed transmit signal obtained from the transmit path, the feedback path comprising a set of adjacent leakage interference (ALI) filters, the feedback path operable to generate an ALI signal that is received at the first receiver component associated with the receive path to reduce effects of ALI at the first receiver component associated with the receive path, the feedback path comprising a second receiver component, a second subtraction component, and a training component configured to train the set of ALI filters by obtaining and processing first signals from the receive path and second signals from the feedback path while the receive path and the feedback path are operating on a channel associated with downstream reception and a first training upstream signal is transmitted on a channel associated with the downstream channel on the transmit path, and estimating filter coefficients for the set of ALI filters;
• a first echo cancellation path for the feedback path being configured to generate a first adjacent channel interference (ACI) signal received at the second subtraction component associated with the feedback path, the first ACI signal determined by processing a sampled upstream signal associated with the transmit path using a first set of ACI filters at the first echo cancellation path, the first set of ACI filters being trained by processing both a second training upstream signal and receiving and processing a first echoed second training upstream signal for the upstream channel from the directional coupler on the feedback path operating on a channel associated with upstream transmission;
• and
• a second echo cancellation path for the receive path being configured to generate a second ACI signal received at the first subtraction component associated with the receive path, the second ACI signal obtained by processing the sampled upstream signal associated with the transmit path using a second set of ACI filters at the second echo cancellation path, the second set of ACI filters being trained by processing both the second training upstream signal and receiving and processing a second echoed second training upstream signal for the upstream channel from the directional coupler on the receive path operating on the channel associated with upstream transmission,
• wherein the transmit path, receive path, first echo cancellation path, and second echo cancellation path are coupled to the directional coupler, and wherein filter coefficients for the first set of ACI filters and the second set of ACI filters is estimated before estimating the filter coefficients for the set of ALI filters.

A method, comprising:

• enabling a directional coupler configured to transmit an upstream signal transmitted by a digital transmitter component associated with a transmit path, and receive a downstream signal on an upstream channel and a downstream channel that are adjacent;
• using a first training component to train a set of adjacent leakage interference (ALI) filters by processing first signals from a receive path and second signals from a feedback path while the receive path and the feedback path operate on a channel associated with downstream reception and a first training upstream signal is transmitted on the channel associated with the downstream channel on the transmit path, wherein the receive path includes a first receiver component and a first subtraction component, and wherein the feedback path includes the set of adjacent leakage interference (ALI) filters, the feedback path operable to generate an ALI signal that is received at the first receiver component associated with the receive path to reduce effects of ALI at the first receiver component associated with the receive path, the feedback path comprising a second receiver component, a second subtraction component, and the first training component;
• enabling a first echo cancellation path for the feedback path that includes a first set of adjacent channel interference (ACI) filters;
• generating a first ACI signal by processing a sampled upstream signal associated with the transmit path using the first set of ACI filters;
• using a second training component to train the first set of ACI filters by processing both a second training upstream signal and receiving and processing a first echoed second training upstream signal for the upstream channel from the directional coupler on the feedback path operating on a channel associated with upstream transmission;
• enabling a second echo cancellation path for the receive path that includes a second set of ACI filters;
• generating a second ACI signal by processing the sampled upstream signal using the second set of ACI filters;
• and
• using the second training component to train the second set of ACI filters by processing both the second training upstream signal and receiving and processing a second echoed second training upstream signal for the upstream channel from the directional coupler on the receive path operating on the channel associated with upstream transmission,
• wherein filter coefficients for the first set of ACI filters and the second set of ACI filters is estimated before estimating filter coefficients for the set of ALI filters.