Dynamic Random Access Resource Size Selection for LTE Coverage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current random access procedures in LTE networks face coverage limitations, especially for low-rate Machine Type Communication devices, due to insufficient power and coverage issues, leading to failed access attempts and increased power ramping requirements.
Innovation Solution
The method involves configuring and selecting multiple random access resources of different sizes based on estimated uplink channel quality, allowing devices to choose suitable resource sizes for transmission, thereby ensuring similar power levels and reducing the need for power ramping, and enabling improved coverage and reduced collision risks.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a single fixed random access resource size is used in LTE networks, then the network configuration is simple, but coverage is insufficient especially for low-rate MTC devices with high path loss
Solution Approach 1:
The patent segments the random access resource into multiple size classes (first random access resource size and second random access resource size) based on device capabilities and channel conditions. This allows devices with different path loss characteristics to select appropriate resource sizes, improving coverage for MTC devices while maintaining network simplicity through standardized segmentation classes.
Solution Approach 2:
The patent changes the resource size parameter dynamically based on estimated uplink channel quality and device requirements. By adjusting the random access resource size according to path loss estimates and device capabilities, the system achieves better coverage without requiring complex custom configurations for each device scenario.
2Reliability
If power ramping is increased to compensate for high path loss, then coverage is improved, but power consumption increases and access attempts fail more frequently
Solution Approach 1:
The patent introduces dynamic resource size selection where devices can choose from multiple random access resource sizes based on their estimated channel conditions. This dynamic adaptation allows devices to use larger resources when path loss is high without needing to continuously increase transmit power, thereby reducing power consumption while maintaining access success rates.
Solution Approach 2:
The system changes the resource size parameter rather than relying solely on power ramping to compensate for path loss. By adjusting the random access resource size up or down based on channel quality estimates, the system achieves better coverage and access success without the associated power consumption penalties of aggressive power ramping.
3Adaptability or versatility
If multiple random access resources of different sizes are configured, then coverage and power efficiency are improved, but device selection complexity increases
Solution Approach 1:
The patent implements self-service by having devices autonomously select the appropriate random access resource size based on their own capabilities and estimated channel conditions. The device independently determines which resource size to use without requiring network intervention or complex manual configuration, thereby maintaining ease of operation while achieving high adaptability.
Solution Approach 2:
The device automatically adjusts the resource size parameter based on pre-configured selection criteria and channel quality estimates. This automated parameter selection process simplifies the device's operation while enabling it to adapt to different coverage scenarios, eliminating the need for complex manual selection procedures.
4Reliability
If larger random access resources are used for all devices, then coverage is improved, but collision risks increase and resource utilization efficiency decreases
Solution Approach 1:
The patent applies local quality by tailoring the random access resource size to specific device needs and channel conditions rather than using a uniform size for all devices. Devices in poor coverage areas use larger resources, while devices in better coverage areas use smaller resources, thereby improving overall coverage without wasting resources on devices that don't need the extra coverage capability.
Solution Approach 2:
The system provides partial coverage enhancement by offering larger random access resources only to devices that need them based on their channel conditions and device type. This partial application of excessive action (larger resources) only where necessary improves coverage for MTC devices while avoiding the collision risks and inefficiency of universally applying large resources to all devices.
Data Source
AI summary
The disclosure relates to connection setup between a wireless device and a mobile communication network using random access, and more specifically to dynamic random access resource configuration and selection. The disclosure provides for a method in a wireless device, of selecting random access resources for performing a random access procedure to a wireless network. The method comprises the step receiving information from a radio network node comprised in a cell of the wireless network, wherein the received information indicates at least a first and a second random access resource having different resource sizes. The method further comprises selecting one of said at least first and a second random access resources based on an expected uplink power received by the radio network node and transmitting a random access message to said wireless network using the selected resource. The disclosure further relates to methods for providing random access resources, as well as to a wireless device, and to radio network nodes of a wireless network.