Connection Admission Control for Broadband Wireless Access
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing Connection Admission Control (CAC) algorithms in Broadband Wireless Access (BWA) systems face challenges in differentiating between Real Time (RT) and Non Real Time (NRT) service connections, handling new connections versus handover connections, and accounting for MAP overhead, which are critical for managing network resources effectively in BWA systems employing Orthogonal Frequency Division Multiple Access (OFDMA) schemes.
Innovation Solution
A CAC method and apparatus that convert transmission request rates into the number of required slots and compare them with available slots, while differentiating service classes to determine connection admission, prioritizing RT and NRT connections, and managing MAP overhead to ensure Quality of Service (QoS).
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If conventional CAC algorithms are used in BWA systems, then connection admission decisions can be made, but the algorithms cannot effectively differentiate between RT and NRT service connections or account for MAP overhead
Solution Approach 1:
The patent segments the CAC process into distinct handling paths for RT and NRT services. RT service CAC checks available capacity against requested rate with strict QoS guarantees, while NRT service CAC uses different logic that accounts for MAP overhead and best-effort allocation. This segmentation enables service-specific optimization without requiring a single complex algorithm to handle all cases uniformly.
Solution Approach 2:
The patent applies local quality by implementing service-specific CAC parameters and thresholds. RT services receive dedicated capacity reservations with guaranteed QoS parameters, while NRT services are allocated from remaining capacity with MAP overhead considerations. Each service type has tailored admission criteria that match its specific requirements, rather than using uniform standards for all services.
2Productivity
If transmission request rate is directly compared with available channel capacity, then CAC decisions can be made quickly, but the comparison does not account for MAP overhead and service class differences
Solution Approach 1:
The patent performs preliminary classification of service types (RT vs. NRT) and preliminary calculation of MAP overhead requirements before the actual capacity comparison. This preliminary action separates the quick classification step from the more complex resource calculation, allowing the system to maintain fast processing while incorporating precise overhead accounting in the appropriate service categories.
Solution Approach 2:
The patent changes the comparison parameters based on service class. For RT services, the comparison uses guaranteed capacity parameters with strict QoS thresholds. For NRT services, the comparison incorporates MAP overhead parameters and best-effort allocation factors. This dynamic parameter adjustment enables both fast processing and accurate resource assessment tailored to each service type.
3Device complexity
If available channel capacity is estimated without considering MAP overhead, then capacity estimation is simpler, but the estimation becomes inaccurate especially as number of users increases
Solution Approach 1:
The patent applies partial action by calculating MAP overhead only for NRT services where it is most impactful, rather than uniformly for all services. The overhead calculation focuses on the specific portions of capacity affected by signaling requirements, applying correction factors selectively to achieve accurate estimation without unnecessarily complicating the entire capacity calculation process.
Data Source
AI summary
Provided are a Connection Admission Control (CAC) method and apparatus in a Broadband Wireless Access (BWA) system. The CAC method includes checking a class of a requested service; converting the transmission request rate of the service into the number of required air resource blocks by using an average block capacity of the checked class; and determining whether to admit or deny connection by comparing the number of required resource blocks with the number of available resource blocks.