Adaptive Filter Offset Injection for Fast Coefficient Steady State

Solution Overview

Problem

Adaptive filters using resource sharing face challenges in achieving fast convergence of filter coefficients, which is crucial for power-efficient implementation, especially in cost-sensitive markets.

Innovation Solution

The introduction of an offset injection technique into the iterative convergence algorithm for adjusting filter coefficients, combined with computational resource sharing, where only a subset of filter coefficients is adjusted at a time, and offsets are periodically injected to enhance convergence rate.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by stationary object

If computational resource sharing is used in adaptive filters, then power consumption and cost are reduced, but convergence rate of filter coefficients deteriorates

Engineering Contradiction:

Improvepower consumptionVSAvoidconvergence rate

Core Design Contradiction:

Use of energy by stationary objectVSSpeed

Solution Approach 1:

The patent applies preliminary action by injecting offsets into filter coefficients before the adaptive convergence algorithm processes them. This pre-adjustment accelerates the convergence process, allowing resource-sharing adaptive filters to achieve fast convergence without requiring full computational resources for every coefficient update. The offset injection prepares the coefficients in advance, compensating for the reduced update frequency caused by resource sharing.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent changes parameters by introducing offset values to the filter coefficients and adjusting the step size parameter dynamically. These parameter modifications enable the filter to converge faster despite using fewer computational resources. By altering the coefficient values through offset injection and adjusting the adaptation step size, the system achieves improved convergence speed while maintaining resource-sharing architecture.

Inventive Principle:

Principle #35Parameter changes

2Device complexity

If computational resource sharing is used in adaptive filters, then device complexity is reduced, but convergence rate of filter coefficients deteriorates

Engineering Contradiction:

Improvecomputational complexityVSAvoidconvergence rate

Core Design Contradiction:

Device complexityVSSpeed

Solution Approach 1:

The patent applies preliminary action by injecting offsets into filter coefficients before the adaptive convergence algorithm processes them. This pre-adjustment accelerates the convergence process, allowing resource-sharing adaptive filters to achieve fast convergence without requiring full computational resources for every coefficient update. The offset injection prepares the coefficients in advance, compensating for the reduced update frequency caused by resource sharing.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent changes parameters by introducing offset values to the filter coefficients and adjusting the step size parameter dynamically. These parameter modifications enable the filter to converge faster despite using fewer computational resources. By altering the coefficient values through offset injection and adjusting the adaptation step size, the system achieves improved convergence speed while maintaining resource-sharing architecture.

Inventive Principle:

Principle #35Parameter changes

3Use of energy by stationary object

If fewer computational blocks are used for coefficient adjustment, then power consumption is reduced, but time to reach steady state increases

Engineering Contradiction:

Improvepower consumptionVSAvoidtime to reach steady state

Core Design Contradiction:

Use of energy by stationary objectVSLoss of time

Solution Approach 1:

The patent applies preliminary action by injecting offsets into filter coefficients before the adaptive convergence algorithm processes them. This pre-adjustment accelerates the convergence process, allowing resource-sharing adaptive filters to achieve fast convergence without requiring full computational resources for every coefficient update. The offset injection prepares the coefficients in advance, compensating for the reduced update frequency caused by resource sharing.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent applies periodic action by injecting offsets at specific intervals during the adaptation process. Rather than continuously updating all coefficients with full computational power, the system periodically injects offsets to nudge the coefficients toward their optimal values. This periodic intervention maintains low power consumption while effectively reducing the time to reach steady state.

Inventive Principle:

Principle #19Periodic action

Data Source

PatentUS10363765B2Adaptive filter and method of operating an adaptive filter

Publication Date: 2019.07.30 NXP BV

AI summary

The present application relates to an adaptive filter using resource sharing and a method of operating the adaptive filter. The filter comprises at least one computational block, a monitoring block and an offset calculation block. The computational block is configured for adjusting a filter coefficient, ci(n), in an iterative procedure according to an adaptive convergence algorithm. The monitoring block is configured for monitoring the development of the determined filter coefficient, ci(n), during the performing of the iterative procedure. The offset calculation block is configured for determining an offset, Offi, based on a monitored change of the filter coefficient, ci(n), each first time period, T1, and for outputting the determined offset, Offi, to the computational block if the determined filter coefficient, ci(n), has not reached the steady state. The computational block is configured to accept the determined offset, Offi, and to inject the determined offset, Offi, into the iterative procedure.