Payload-less PUMICH Design for Uplink Mobility
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current wireless communication systems face challenges in uplink-based mobility, particularly in reducing power consumption and interference, as UEs frequently wake up to perform cell searches, leading to battery life issues and potential missed paging signals due to independent paging from each cell in downlink-based mobility.
Innovation Solution
A payload-less Physical Uplink Measurement Indication Channel (PUMICH) design is introduced, where UEs transmit selected random access procedure sequences without data payloads, allowing the network to perform cell search and selection based on uplink reference signals, reducing power consumption and interference by coordinating paging across cells.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If UEs frequently wake up to perform cell searches in downlink-based mobility, then cell selection can be performed, but power consumption increases and battery life decreases
Solution Approach 1:
The patent inverts the traditional downlink-based mobility approach by implementing uplink-based mobility. Instead of the UE waking up to receive downlink paging signals and perform cell searches, the UE remains in a low-power state and the network initiates cell search by transmitting wake-up signals and measurement reference signals on the uplink. This inversion fundamentally reduces UE power consumption while maintaining cell selection capability.
Solution Approach 2:
The network performs cell search and measurement functions that traditionally required UE activation. By having the network transmit wake-up signals and measurement reference signals, and process the uplink transmissions for cell selection, the system enables cell search functionality without requiring the UE to wake up and consume power for these operations.
2Reliability
If each cell transmits independent paging signals in downlink-based mobility, then paging can be delivered, but interference increases and network efficiency decreases
Solution Approach 1:
The patent merges the paging functionality across multiple cells by implementing coordinated paging in uplink-based mobility. Instead of each cell independently transmitting paging signals on the downlink, the network coordinates paging transmissions, allowing multiple cells to share the same uplink resources for wake-up signals and measurement reference signals. This coordination reduces interference and improves network efficiency while maintaining reliable paging delivery.
3Loss of information
If UEs transmit with data payloads in traditional random access, then information can be conveyed, but power consumption and interference increase
Solution Approach 1:
The patent extracts the essential identification function from the data payload by using purified random access sequences. Instead of transmitting full data payloads with information, the system uses specially designed random access sequences that inherently encode UE identification and measurement information. This extraction of the core function removes the need for power-consuming data transmission while maintaining information conveyance capability.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Certain aspects of the present disclosure provide techniques for payload-less physical uplink measurement indication channel (PUMICH) design for uplink based mobility. According to certain aspects, a method of wireless communication by a base station (BS) is provided. The method generally includes selecting a first set of random access procedure (RACH) sequences from a second set of RACH sequences, wherein the second set of RACH sequences comprises a pruned set of RACH sequences, and wherein at least some of the first set of RACH sequences selected for a first user equipment (UE) is also available for selection for a second UE, and transmitting the selected first set of RACH sequences to a UE in response to a request from the UE.