Dynamic Pilot Signal Allocation for Wireless Channel Estimation

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Solution Overview

Problem

In wireless communication systems, channel estimation using pilot signals is a trade-off between accuracy and data bandwidth, and existing methods do not effectively adapt to changing relative speeds between transmitters and receivers, leading to potential frame error rate increases and throughput reductions.

Innovation Solution

A method and device for allocating pilot signals in a multi-user, multi-carrier wireless communication system that dynamically adjusts pilot signal density based on the relative speed between communication stations, allowing for more accurate channel estimation without compromising throughput by allocating higher pilot signal densities at higher relative speeds and lower densities at lower speeds.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If more pilot signals are used, then channel estimation accuracy is improved, but data bandwidth is reduced

Engineering Contradiction:
Improvechannel estimation accuracyVSAvoiddata bandwidth
Core Design Contradiction:
Measurement precisionVSProductivity

Solution Approach 1:

The patent applies dynamics by making the pilot signal allocation density variable rather than fixed. The system dynamically adjusts pilot signal density based on detected relative speed, using higher density for high-speed stations and lower density for low-speed stations. This dynamic adaptation resolves the contradiction by optimizing the trade-off between channel estimation accuracy and data bandwidth according to actual channel conditions.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent changes the parameter of pilot signal density based on relative speed conditions. By detecting the relative speed between transmitter and receiver and adjusting pilot signal density accordingly, the system transforms a static parameter into a variable one, achieving both accurate channel estimation and efficient data transmission under different mobility conditions.

Inventive Principle:
Principle #35Parameter changes

2Productivity

If less pilot signals are used, then data bandwidth is improved, but frame error rate increases

Engineering Contradiction:
Improvedata bandwidthVSAvoidframe error rate
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The system dynamically adjusts pilot signal density based on relative speed detection. For high-speed communication stations experiencing rapid channel changes, higher pilot density maintains reliability and reduces frame error rates. For low-speed stations with stable channels, lower pilot density suffices, maintaining reliability while preserving data bandwidth.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent changes pilot signal density parameters according to relative speed conditions, ensuring adequate channel estimation accuracy is maintained for reliable data transmission. This parameter adaptation prevents frame errors by ensuring sufficient pilot signals are present under conditions where channel variations would otherwise cause estimation failures.

Inventive Principle:
Principle #35Parameter changes

3Ease of manufacture

If pilot signals are allocated uniformly, then implementation simplicity is maintained, but adaptability to different relative speeds is reduced

Engineering Contradiction:
Improveimplementation simplicityVSAvoidadaptability to relative speed
Core Design Contradiction:
Ease of manufactureVSAdaptability or versatility

Solution Approach 1:

The patent implements a dynamic pilot allocation scheme where the system detects relative speed and automatically adjusts pilot signal density accordingly. This dynamic approach provides adaptability to different mobility conditions while maintaining implementation simplicity through automated detection and adjustment, eliminating the need for complex manual configuration.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The system performs self-service by automatically detecting relative speed conditions and adjusting pilot signal density without external intervention. The communication station autonomously adapts its pilot allocation based on its own mobility characteristics, providing both adaptability and operational simplicity.

Inventive Principle:
Principle #25Self-service

Data Source

PatentEP1965551B1Methods and devices for allocating pilots in a wireless communication system
Publication Date: 2015.03.25 IND TECH RES INST
  • EP1965551B1 patent drawingFigure 1A~1C
  • EP1965551B1 patent drawingFigure 2A
  • EP1965551B1 patent drawingFigure 2B

AI summary

A method of data communication in a multi-user, multi-carrier wireless communication system, the method comprising identifying a resource region including a plurality of symbols, allocating pilot signals to the resource region, identifying pilot-free symbols free of the pilot signals in the plurality of symbols, arranging sacrifice carriers for a first region of a group of symbols in the pilot-free symbols at a first density for a first communication station, and arranging sacrifice carriers for a second region of the group of symbols in the pilot-free symbols at a second density for a second communication station, wherein the first communication station is mobile with respect to an access communication station at a first relative speed and the second communication station is mobile with respect to the access communication station at a second relative speed, and wherein the first density of sacrifice carriers is greater than the second density of sacrifice carriers if the first relative speed is greater than the second relative speed.