Mobile Station Doppler Shift Management via Base Station Selection

Solution Overview

Problem

In mobile radio communication systems, high-speed movement of mobile stations between base stations causes frequency shifts in uplink signals due to Doppler effect, leading to increased operational complexity, power consumption, and heat emission when correcting these shifts to maintain communication quality.

Innovation Solution

A mobile station detects changes in relative positions to base stations and selectively chooses an uplink signal reception base station that is moving away and a downlink signal transmission base station that is moving towards it, ensuring frequency shifts are consistently in one direction, thereby eliminating the need for frequency correction processing.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If frequency correction processing is performed to correct Doppler-induced frequency shifts in uplink signals, then communication quality is maintained, but operational complexity, power consumption, and heat emission increase

Engineering Contradiction:

Improvecommunication qualityVSAvoidoperational complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent converts the harmful Doppler frequency shift into a beneficial selection criterion by choosing base stations such that the mobile station receives downlink signals from base stations moving away and transmits uplink signals to base stations moving towards. This strategic selection transforms the unavoidable Doppler effect into a mechanism that maintains frequency consistency and eliminates the need for complex frequency correction processing

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

Solution Approach 2:

Instead of correcting frequency shifts after they occur (conventional approach), the patent inverts the approach by preemptively selecting base stations based on their motion relative to the mobile station. This inversion prevents frequency shifts from causing communication quality degradation in the first place, avoiding the need for corrective processing

Inventive Principle:

Principle #13The other way round (Inversion)

2Reliability

If frequency correction processing is performed to correct Doppler-induced frequency shifts in uplink signals, then communication quality is maintained, but power consumption increases

Engineering Contradiction:

Improvecommunication qualityVSAvoidpower consumption

Core Design Contradiction:

ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent converts the harmful Doppler frequency shift into a beneficial selection criterion by choosing base stations such that the mobile station receives downlink signals from base stations moving away and transmits uplink signals to base stations moving towards. This strategic selection transforms the unavoidable Doppler effect into a mechanism that maintains frequency consistency and eliminates the need for power-consuming frequency correction processing

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

3Reliability

If frequency correction processing is performed to correct Doppler-induced frequency shifts in uplink signals, then communication quality is maintained, but heat emission increases

Engineering Contradiction:

Improvecommunication qualityVSAvoidheat emission

Core Design Contradiction:

ReliabilityVSTemperature

Solution Approach 1:

The patent converts the harmful Doppler frequency shift into a beneficial selection criterion by choosing base stations such that the mobile station receives downlink signals from base stations moving away and transmits uplink signals to base stations moving towards. This strategic selection transforms the unavoidable Doppler effect into a mechanism that maintains frequency consistency and eliminates the need for heat-generating frequency correction processing

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This approach maintains communication quality without increasing operational complexity or power consumption, as frequency shifts are consistently managed, preventing signal quality degradation and maintaining throughput.

Implementation Method 1

high-speed movement of mobile stations between base stations causes frequency shifts in uplink signals due to Doppler effect

Methodology Applied

Scientific EffectDoppler effect: Doppler Effect

Data Source

PatentUS8880077B2Mobile station, a mobile radio communication system, and a mobile radio communication method

Publication Date: 2014.11.04 LENOVO INNOVATIONS LTD (HONG KONG)

AI summary

In a mobile radio communication method in which a mobile station moves among a plurality of base stations at high speed, in order to solve a problem of increase in the amount of operation and its related increase in the amount of power consumption and heat emission which is resulted for maintaining good communication quality of communication by the mobile station which moves at high speed to the direction for approaching the base station or moving away from it, it provides detecting means for detecting changes in relative positions to a plurality of base stations, and selecting means for selecting an uplink signal reception base station which receives an uplink signal and selecting one or plural base stations, fluctuation of increase and decrease of which of distance from own mobile station is an opposite manner compared with a case of the uplink signal receiving base station, based on changes in the relative positions detected by said detecting means as a downlink signal transmission base station which transmits a downlink signal.