Random Access Response Window Determination in Satellite Communication

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

In satellite communication systems, determining an accurate random access response window is challenging due to varying delay requirements, leading to unnecessary additional delay, increased detection overhead, and resource wastage.

Innovation Solution

The method involves obtaining the number of repeated transmissions of a narrowband physical random access channel (NPRACH) and the round-trip time (RTT) between devices to determine the start position of the random access response window, thereby avoiding additional delay.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If timing offset Koffset is introduced to compensate transmission delay, then communication reliability is improved, but unnecessary additional delay is increased

Engineering Contradiction:

Improvecommunication reliabilityVSAvoidadditional delay

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The patent applies dynamics by making the timing offset Koffset adjustable rather than fixed. The network device dynamically determines the appropriate Koffset value based on the specific scenario and delay requirements, allowing the system to adapt between prioritizing reliability or minimizing delay depending on conditions

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent changes the parameter Koffset based on different scenarios. By adjusting this timing offset parameter according to specific communication conditions and delay requirements, the system optimizes the balance between reliability compensation and delay minimization

Inventive Principle:

Principle #35Parameter changes

2Device complexity

If a fixed random access response window is used, then device complexity is reduced, but detection overhead increases and resources are wasted

Engineering Contradiction:

Improvedevice complexityVSAvoiddetection overhead

Core Design Contradiction:

Device complexityVSLoss of energy

Solution Approach 1:

The patent makes the random access response window dynamic by determining its start position and duration based on the number of NPRACH repetitions and RTT. This allows the window to be optimized for each specific access scenario, reducing detection overhead and resource waste while maintaining manageable device complexity through standardized determination rules

Inventive Principle:

Principle #15Dynamics

3Reliability

If the number of NPRACH repetitions is increased, then communication reliability is improved, but transmission delay increases

Engineering Contradiction:

Improvecommunication reliabilityVSAvoidtransmission delay

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The patent applies preliminary action by having the network device determine and notify the terminal of the random access response window parameters before the terminal needs to monitor for the response. This allows the terminal to efficiently monitor only during the determined window period, reducing detection overhead while supporting reliable communication even with multiple repetitions

Inventive Principle:

Principle #10Preliminary action

Data Source

PatentUS20250119942A1Method and communication device for determining random access response window

Publication Date: 2025.04.10 BEIJING XIAOMI MOBILE SOFTWARE CO LTD

AI summary

A method, apparatus and computer readable medium for determining a random access response window in a wireless communication systems such as a long term evolution (LTE) system, a 5th generation (5G) mobile communication system, a 5G new radio (NR) system, or other mobile communication systems. The random access response window is determined by: obtaining the number of repeated transmissions of a narrowband physical random access channel (NPRACH); obtaining a round-trip time (RTT) between a first device and a second device; and determining a start position of a random access response window.