OFDMA Peer-to-Peer Scheduling to Mitigate Near-Far Interference
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Solution Overview
Problem
Existing OFDMA wireless communication systems face challenges in managing near-far problems during peer-to-peer communications, as conventional TDMA scheduling techniques are ineffective in mixed networks with direct station-to-station communication, leading to significant interference issues.
Innovation Solution
The implementation of proactive and reactive scheduling methods that involve a base station generating and broadcasting Grant Metric Information Elements and Resource Map Information Elements, allowing stations to measure and report Quality-of-Service metrics, and dynamically allocate resources to prevent near-far interference by identifying and managing peer stations' interference levels.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional TDMA scheduling techniques are used in OFDMA systems, then time-orthogonal uplink and downlink transmissions can be achieved, but near-far interference problems occur during peer-to-peer communications
Solution Approach 1:
The patent segments the OFDMA resource space by introducing a peer-to-peer indicator that divides communications into traditional base-station-centric modes and direct peer-to-peer modes. This segmentation allows different scheduling strategies to be applied to different communication types, preventing near-far interference in peer-to-peer links while maintaining TDMA benefits for traditional communications.
Solution Approach 2:
The patent implements dynamic resource allocation where the base station scheduler dynamically assigns time slots and sub-channels for peer-to-peer communications based on real-time channel conditions and interference levels. The peer-to-peer indicator and dynamic scheduling allow the system to adapt resource allocation continuously, optimizing performance while avoiding near-far problems.
2Productivity
If peer-to-peer communication is enabled in OFDMA systems, then direct station-to-station communication efficiency is improved, but interference management complexity increases
Solution Approach 1:
The base station acts as an intermediary that manages peer-to-peer communications by assigning specific time slots and sub-channels for direct station-to-station links. The base station scheduler coordinates peer-to-peer resource allocation, maintaining centralized control while enabling direct communications, thus improving efficiency without excessive complexity at the station level.
Solution Approach 2:
The patent creates a universal scheduling framework that handles both traditional base-station-centric communications and peer-to-peer communications through a single base station scheduler. The peer-to-peer indicator enables the same scheduling infrastructure to serve multiple communication modes, reducing overall system complexity while supporting diverse communication types.
3Productivity
If high-power transmissions are allowed in the same time slot, then resource utilization is improved, but desensitization of receivers occurs
Solution Approach 1:
The patent segments the time-frequency resource space by assigning peer-to-peer communications to specific time slots marked with a peer-to-peer indicator. This segmentation isolates high-power peer transmissions from other communications, allowing high resource utilization while preventing receiver desensitization through temporal and spatial separation.
Solution Approach 2:
The system uses periodic time slots designated for peer-to-peer communications, creating a structured pattern of high-power transmissions. By confining these transmissions to specific periodic intervals with proper scheduling, the system maximizes resource utilization while ensuring receivers are not desensitized during non-peer time slots.
Data Source
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AI summary
Systems, methods and apparatus are provided for scheduling resources in Orthogonal Frequency-Division Multiple Access (OFDMA) communication networks for "direct link" or peer-to-peer communications among stations operating therein so that OFDMA resources can be allocated to a transmitter station for a peer-to-peer communication session with a receiver station such that near-far issues caused by peer-to-peer communication are reduced/avoided. The disclosed technologies can prevent peer-to-peer communication links using different sub-channels within the same time slot from creating near-far issues for other receiver stations that are within communication range.