E-FACH Terminal Neighbor Cell List Update Logic
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In the E-FACH state of a TDD-SCDMA system, terminals face challenges in processing system information and measurement control messages due to inconsistent frequency references, leading to incorrect neighbor cell list updates and failure in cell re-selection, resulting in service disruptions and poor user experience.
Innovation Solution
The terminal processes system information and measurement control messages based on its current working carrier frequency, establishing and updating neighbor cell lists differently depending on whether it operates on a main or subordinate carrier frequency, ensuring accurate cell re-selection and measurement evaluations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the terminal monitors system information without discriminating current working frequency point, then the terminal can receive system information, but the terminal cannot determine correct neighbor relations when working on subordinate carrier frequency
Solution Approach 1:
The patent applies local quality by making the system information processing frequency-dependent. When the terminal works on the main carrier frequency, it processes system information normally to obtain neighbor relations. When working on a subordinate carrier frequency, the terminal identifies the frequency mismatch and adjusts its processing accordingly, applying different logic based on the local frequency context.
Solution Approach 2:
The patent changes the processing parameter based on the working frequency. The terminal detects whether it is operating on the main or subordinate carrier frequency and changes its neighbor cell list update behavior accordingly. This parameter change (frequency state) triggers different processing modes to resolve the contradiction.
2Reliability
If the terminal updates neighbor cell list based on system information, then the terminal can maintain neighbor relations, but the terminal cannot correctly identify intra-frequency and inter-frequency cells when working on subordinate carrier frequency
Solution Approach 1:
The patent introduces an intermediary judgment step: the terminal first determines whether it is working on the main or subordinate carrier frequency before processing neighbor cell information. This intermediary frequency-state detection acts as a mediator that resolves the ambiguity between system information frequency reference (main carrier) and actual working frequency (subordinate carrier), enabling correct neighbor relation identification.
3Reliability
If the terminal receives measurement control message, then the terminal can perform measurement evaluation, but the terminal cannot determine whether measurement indication is for measurement evaluation or re-selection
Solution Approach 1:
The patent applies preliminary action by having the terminal determine its working frequency state (main or subordinate carrier) before processing the measurement control message. This preliminary frequency-state identification enables the terminal to correctly interpret the measurement indication and determine whether it applies to measurement evaluation, re-selection, or both, resolving the ambiguity in message interpretation.
Data Source
Figure 1~3
Figure 4~6
AI summary
The disclosure discloses a method for processing cell information in an Enhanced Forward Access Channel (E-FACH) state, which includes: when a terminal in the E-FACH state determines that a working carrier frequency thereof is a subordinate carrier frequency, the terminal establishes a neighbor cell list for the terminal itself using cell information in received system information, or the terminal waits for receiving a measurement control message from a network side, and establishes a neighbor cell list for the terminal itself using cell information in the received measurement control message, or the terminal establishes a neighbor cell list for the terminal itself using cell information in received system information, and updates the established neighbor cell list according to cell information in a received measurement control message. Moreover, the disclosure discloses a device for processing cell information in an E-FACH state to implement the above method. The disclosure is a very good supplement to a method in an existing protocol for a terminal to process system information and a measurement control message in an E-FACH state, thus solving the problem in the existing protocol that a neighbor cell is unable to be re-selected because the neighbor cell list cannot be updated.