Super-Frame Minislot Allocation for Cable Modem Bandwidth Grants
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The complexity of distributing data over multiple upstream communication channels in cable communications systems increases significantly with channel bonding, leading to high latency and increased complexity in managing minislot numbering and timing relationships across channels.
Innovation Solution
A cable modem system that uses a super-frame arrangement to distribute data across multiple communication channels, where a sequence of data is fragmented into portions and transmitted over multiple minislots across multiple channels, with the media access controller configuring the transmission based on upstream bandwidth grants and information carrying capabilities of each set of minislots.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If channel bonding is used to transmit data over multiple upstream communication channels simultaneously, then data throughput is improved, but system complexity and latency increase due to managing minislot numbering and timing relationships across channels
Solution Approach 1:
The patent combines multiple minislot numberings from different upstream communication channels into a single unified minislot numbering scheme. This allows the cable modem to track and manage all minislots across bonded channels using one continuous counter, eliminating the complexity of maintaining separate minislot counters for each channel while preserving the ability to distribute data efficiently across multiple channels.
2Adaptability or versatility
If separate minislot numbering is used for each upstream communication channel, then channel independence is maintained, but latency increases due to difficulty in coordinating bandwidth grants across channels
Solution Approach 1:
The patent segments the unified minislot numbering into channel-specific minislot ranges while maintaining a continuous global counter. This allows the system to identify which channel a particular minislot belongs to and coordinate bandwidth grants across channels effectively, reducing latency by enabling the cable modem to track and transmit data across channels in the correct temporal sequence.
3Adaptability or versatility
If independent PHY layer parameters are configured for each upstream communication channel, then adaptation to channel conditions is improved, but complexity of managing timing and slot relationships increases
Solution Approach 1:
The patent creates a universal minislot numbering framework that works across all upstream communication channels regardless of their individual PHY layer configurations. This single numbering scheme adapts to different channel conditions by allowing each channel to have its own timing characteristics while maintaining a consistent reference frame for the cable modem to manage all channels uniformly.
Data Source
Figure 1
Figure 2A
Figure 2B
AI summary
A cable modem termination system (CMTS) is disclosed that allocates one or more minislots of a super-frame arrangement to cable modems for upstream transmission. The super-frame arrangement includes multiple minislots that correspond to multiple communication channels of one or more super-frames. The CMTS receives requests for upstream bandwidth from the cable modems. The CMTS continuously allocates the minislots of the super-frame to provide upstream bandwidth grants to accommodate these requests. The CMTS communicates the upstream bandwidth grants as a single upstream bandwidth allocation map (MAP) to the cable modems.