GPS Signal Acquisition Using Addition-Subtraction Correlation

Solution Overview

Problem

Existing GPS satellite signal acquisition methods require extensive correlation computation, leading to increased circuit scale and power consumption due to the need for multiplication and integration of sampling values and replica codes.

Innovation Solution

A method that selects every k sampling values from a time series, performs addition-subtraction operations on these values, and calculates correlation results without multiplication, using addition-subtraction results to determine the satellite signal, thereby reducing computational complexity and power consumption.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If correlation computation is performed by multiplying and integrating sampling values of reception signal and replica code for each phase shift, then accurate satellite signal acquisition is achieved, but circuit scale and power consumption increase

Engineering Contradiction:

Improvesignal acquisition accuracyVSAvoidpower consumption

Core Design Contradiction:

Measurement precisionVSUse of energy by moving object

Solution Approach 1:

The patent changes the computational parameters by replacing multiplication operations with addition-subtraction operations. Specifically, it uses the property that multiplying by +1 or -1 can be achieved through addition or subtraction of the original value, thereby reducing computational complexity and power consumption while maintaining correlation computation accuracy for satellite signal acquisition

Inventive Principle:

Principle #35Parameter changes

2Measurement precision

If correlation computation is performed by multiplying and integrating sampling values of reception signal and replica code for each phase shift, then accurate satellite signal acquisition is achieved, but circuit scale increases

Engineering Contradiction:

Improvesignal acquisition accuracyVSAvoidcircuit scale

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent changes the computational parameters by replacing multiplication operations with addition-subtraction operations. Specifically, it uses the property that multiplying by +1 or -1 can be achieved through addition or subtraction of the original value, thereby reducing computational complexity and power consumption while maintaining correlation computation accuracy for satellite signal acquisition

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS8842718B2Method of capturing satellite signal and device for capturing satellite signal

Publication Date: 2014.09.23 SEIKO EPSON CORP

AI summary

Every k (k≧2) sampling values of sampling values in a time series obtained by sampling reception signal from GPS satellite are selected, and addition-subtraction of the selected k sampling values is performed by changing the combinations of addition and subtraction. Using addition-subtraction results of a combination corresponding to time-series change in code values of a replica code from among the combinations of addition and subtraction, a correlation result of the reception signal and the replica code is calculated. The satellite signal of the GPS satellite is acquired using the correlation result.