Complex-Signal Digital Filtering With Selective Conjugate Processing

Solution Overview

Problem

Digital filters require high power consumption and generate significant heat during filter processing due to the processing of complex signals and their conjugates in the frequency domain.

Innovation Solution

A digital filter circuit that includes a separation unit to generate complex conjugate signals, a signal selection unit to switch between different signal amplitudes, and filter units to perform processing using specific filter coefficients, reducing power consumption by optimizing signal processing modes.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If filter processing is performed on both the second complex signal and its complex conjugate (third complex signal), then complete filter processing coverage is achieved, but power consumption and heat generation increase significantly

Engineering Contradiction:

Improvefilter processing completenessVSAvoidpower consumption

Core Design Contradiction:

ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent extracts only the necessary signal processing path by selectively processing either the second complex signal or its complex conjugate (third complex signal) based on amplitude change requirements, rather than processing both signals completely. This extraction approach reduces redundant computations and lowers power consumption while maintaining filter processing effectiveness for the required signal components.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent applies partial action by performing filter processing on only one of the two complex signals (second or third) depending on which has smaller amplitude changes, rather than processing both signals fully. This partial processing approach achieves sufficient filter effectiveness for the application while significantly reducing the computational load and power consumption associated with processing both signals.

Inventive Principle:

Principle #16Partial or excessive action

2Reliability

If filter processing is performed on both the second complex signal and its complex conjugate (third complex signal), then complete filter processing coverage is achieved, but heat generation increases significantly

Engineering Contradiction:

Improvefilter processing completenessVSAvoidheat generation

Core Design Contradiction:

ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The patent extracts only the necessary signal processing path by selectively processing either the second complex signal or its complex conjugate (third complex signal) based on amplitude change requirements, rather than processing both signals completely. This extraction approach reduces redundant computations and lowers power consumption while maintaining filter processing effectiveness for the required signal components.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent applies partial action by performing filter processing on only one of the two complex signals (second or third) depending on which has smaller amplitude changes, rather than processing both signals fully. This partial processing approach achieves sufficient filter effectiveness for the application while significantly reducing the computational load and power consumption associated with processing both signals.

Inventive Principle:

Principle #16Partial or excessive action

3Measurement precision

If signal processing is performed on complex signals with larger amplitude changes, then processing accuracy is maintained, but power consumption increases

Engineering Contradiction:

Improvesignal processing accuracyVSAvoidpower consumption

Core Design Contradiction:

Measurement precisionVSUse of energy by moving object

Solution Approach 1:

The patent applies partial action by performing filter processing on only one of the two complex signals (second or third) depending on which has smaller amplitude changes, rather than processing both signals fully. This partial processing approach achieves sufficient filter effectiveness for the application while significantly reducing the computational load and power consumption associated with processing both signals.

Inventive Principle:

Principle #16Partial or excessive action

Solution Approach 2:

The patent changes the selection parameter dynamically by comparing amplitude changes between the second complex signal and its complex conjugate, and selecting the signal with smaller amplitude changes for processing. This parameter-based selection strategy optimizes the balance between processing accuracy and power consumption by adapting to the actual signal characteristics.

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS10855255B2Digital filter, filter processing method, and recording medium

Publication Date: 2020.12.01 NEC CORP

AI summary

The present invention addresses the problem of increasing the likelihood of making it possible to reduce the consumption of power necessary for filter processing and the amount of heat generated during filter processing. In order to overcome this problem, a second complex signal and a third complex signal are generated from a first complex signal in a frequency domain, the third complex signal being a complex conjugate of the second complex signal. Signal selection is performed from the plurality of types of complex signals having different amounts of change in signal amplitude. Processing is performed on the complex signal selected as the signal using a first filter coefficient and a second filter coefficient. The complex signals after filter processing are synthesized to generate a complex signal, which is then outputted.