Multicast Paging for IoT Terminals in Unlicensed Spectrum
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current Internet of Things (IoT) systems, particularly in the enterprise IoT (eIoT) market, lack a multicast mechanism and support for physical downlink control channels, leading to inefficiencies in command delivery and increased latency when communicating with a large number of devices.
Innovation Solution
Implementing a multicast communication method in unlicensed spectrum systems by grouping terminals and using a combination of group identifiers and physical channels to transmit paging messages efficiently, allowing for simultaneous communication with multiple devices.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If unicast mode is used to deliver commands to each terminal individually, then reliability is ensured, but command delivery latency increases significantly when there are a large quantity of users
Solution Approach 1:
The patent merges multiple unicast transmissions into a single multicast transmission by combining data from multiple terminals into one group common transport block. The access network device receives uplink data from multiple terminals, combines them into a single transport block, and transmits it via PDSCH to multiple terminals simultaneously. This resolving the contradiction by achieving both reliability (through proper combining and acknowledgment mechanisms) and low latency (through simultaneous delivery to all group members).
Solution Approach 2:
The patent implements a universal multicast mechanism that can serve multiple functions: it enables group common PDSCH transmission, supports group common PDCCH for scheduling, and provides a framework that works for different group sizes and configurations. The group common transport block can carry data from any number of terminals in the group, making the system universally applicable to various eIoT scenarios.
2Productivity
If multicast mechanism is implemented in eIoT system, then system efficiency is improved, but the system complexity increases due to lack of PDCCH support
Solution Approach 1:
The patent extracts the scheduling function from the traditional PDCCH and implements it through group common PDCCH transmissions. Instead of requiring complex PDCCH monitoring for each terminal, the system uses simplified group common PDCCH messages that provide scheduling information for the group common PDSCH. This extraction of essential scheduling functionality while removing unnecessary complexity enables multicast without requiring full PDCCH support.
Solution Approach 2:
The patent creates a simplified copy of the traditional downlink control channel functionality tailored for multicast. The group common PDCCH copies the essential scheduling and resource allocation functions of PDCCH but in a simplified form that is appropriate for group communications. This copying approach allows the system to implement multicast with reduced complexity by using a streamlined control channel design.
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
This application provides a communication method and a communications device. The method includes: receiving, by an access network device from a core network device, a first group identifier of a first terminal group and an identifier of a terminal included in the first terminal group; and sending, by the access network device, the first group identifier and a second group identifier of the first terminal group to the terminal included in the first terminal group. The first group identifier and the second group identifier are used to indicate a paging occasion for the first terminal group, and a paging message for the first terminal group is transmitted on a first physical channel. The technical solutions in the embodiments of this application can improve system efficiency.