LTE System Information Block Scheduling for Limited-Capability UE
Solution Overview
Problem
Low-cost, low-power UE devices in LTE wireless communication systems face inefficiencies in power consumption due to the need to receive unnecessary system information, which exceeds their operational requirements, particularly in machine-to-machine (M2M) applications where data transmission is infrequent and latency tolerant.
Innovation Solution
A method and apparatus for communicating system information in LTE wireless communication systems, where a base station transmits a system information block (SIB) in a configuration receivable by limited-capability UE, including a schedule of additional SIBs, and a Master Information Block (MIB) with an extended System Frame Number (SFN) count, allowing UE to decode scheduling information efficiently, and enables random access calls within specific timing and frequency ranges to align with UE operating requirements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If limited-capability UE devices receive all standard SIBs and MIBs as required by LTE specifications, then system compatibility and information completeness are maintained, but power consumption increases unnecessarily
Solution Approach 1:
The patent extracts only the essential SIBs (SIB1 and SIB2) that limited-capability UE devices need for operation, excluding unnecessary SIBs. The base station identifies and transmits only these critical system information blocks, reducing the information burden on low-power devices while maintaining their operational compatibility.
Solution Approach 2:
The patent applies different information transmission strategies for different UE types. Limited-capability UEs receive a streamlined set of SIBs optimized for their constraints, while full-capability UEs receive the complete SIB set. This localized quality adjustment ensures each device type receives appropriate information without waste.
2Loss of information
If the base station transmits complete system information blocks to all UEs, then information completeness is ensured, but transmission overhead and network power consumption increase
Solution Approach 1:
The base station extracts and transmits only the essential SIBs (SIB1 and SIB2) that limited-capability UEs require, removing unnecessary SIB transmissions. This extraction approach ensures information completeness for the target device class while reducing overall network transmission energy consumption.
Solution Approach 2:
The patent applies partial action by transmitting a subset of SIBs rather than the complete set to all UEs. For limited-capability devices, only the necessary portion (SIB1 and SIB2) is transmitted, avoiding excessive information transmission and associated energy waste while maintaining sufficient operational information.
3Use of energy by moving object
If limited-capability UE devices operate with reduced functionality, then power consumption and cost are reduced, but system information reception capability is limited
Solution Approach 1:
The base station performs preliminary identification of limited-capability UEs and proactively transmits the essential SIBs (SIB1 and SIB2) in a format and timing optimized for these devices. This preliminary action ensures that when limited-capability UEs need system information, it is already available in their receivable format, maintaining reception reliability without requiring full UE capability.
Data Source
AI summary
A method and apparatus for communicating system information and random access in a wireless communication system in an LTE system is provided. In some embodiments, a system information block (SIB) is transmitted in a configuration that is receivable by a limited-capability UE. The SIB may indicate a schedule of additional SIBs transmitted in the same configuration. The schedule may also be transmitted in another manner which is beyond capabilities of the UE to receive but within capabilities of full-capability UEs. Legacy SIB data may be spread between multiple new SIBs in this configuration. The configuration may include a limited transport block size and use of a limited number of physical resource blocks. Also provided is a Master Information Block (MIB) which indicates an extended System Frame Number count. Also provided is a means for communicating operating requirements from a UE by varying the timing and frequency of random access calls.