CFO Prediction for Multi-Packet Receiver Latency Reduction

Solution Overview

Problem

Current technologies for simultaneous reception of collided packets, such as the EverScale technology, face inefficiencies due to the time-consuming and complex process of exhaustive search for carrier frequency offset (CFO) estimation, which increases latency and processing complexity.

Innovation Solution

A machine-learning-based CFO prediction mechanism that tracks measured CFOs and transmitter behavior to predict expected CFO ranges, allowing receivers to prioritize dynamically selected CFOs for efficient frequency demodulation and packet extraction, reducing the need for exhaustive searches.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If exhaustive search over possible CFO range is used for decoding collided packets, then decoding accuracy is improved, but processing time and system complexity increase significantly

Engineering Contradiction:

ImproveCFO estimation accuracyVSAvoidprocessing time

Core Design Contradiction:

Measurement precisionVSLoss of time

Solution Approach 1:

The system performs preliminary tracking of measured CFOs and transmitter behavior over a period of activity before actual packet reception. This preliminary action builds a historical database of CFO values and transmitter patterns, enabling the system to predict likely CFO ranges in advance rather than searching exhaustively when packets arrive, thus reducing processing time while maintaining accuracy

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system continuously tracks and monitors CFO measurements and transmitter behavior, using this feedback to update predictions dynamically. The feedback loop refines the predicted CFO ranges based on observed patterns, allowing the system to adapt to changing conditions while avoiding exhaustive searches, thereby reducing processing time without sacrificing decoding accuracy

Inventive Principle:

Principle #23Feedback

2Measurement precision

If exhaustive search over possible CFO range is performed, then all colliding packets can be decoded accurately, but device complexity and computational burden increase

Engineering Contradiction:

Improvepacket decoding accuracyVSAvoidsystem complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The system performs preliminary tracking of measured CFOs and transmitter behavior over a period of activity before actual packet reception. This preliminary action builds a historical database of CFO values and transmitter patterns, enabling the system to predict likely CFO ranges in advance rather than searching exhaustively when packets arrive, thus reducing processing time while maintaining accuracy

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system continuously tracks and monitors CFO measurements and transmitter behavior, using this feedback to update predictions dynamically. The feedback loop refines the predicted CFO ranges based on observed patterns, allowing the system to adapt to changing conditions while avoiding exhaustive searches, thereby reducing processing time without sacrificing decoding accuracy

Inventive Principle:

Principle #23Feedback

3Productivity

If prioritized CFO list based on prediction is used, then processing efficiency is improved, but risk of missing unexpected CFO values increases

Engineering Contradiction:

Improveprocessing efficiencyVSAvoidpacket detection reliability

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The system performs a prioritized search through predicted CFO ranges first, and only performs exhaustive search for remaining packets if needed. This partial action approach handles the majority of cases efficiently through prediction while having a fallback mechanism, achieving high productivity without completely sacrificing reliability

Inventive Principle:

Principle #16Partial or excessive action

Solution Approach 2:

The system performs preliminary tracking of measured CFOs and transmitter behavior over a period of activity before actual packet reception. This preliminary action builds a historical database of CFO values and transmitter patterns, enabling the system to predict likely CFO ranges in advance rather than searching exhaustively when packets arrive, thus reducing processing time while maintaining accuracy

Inventive Principle:

Principle #10Preliminary action

Data Source

PatentUS10797805B1Optimized frequency searching for simultaneously received packet detection

Publication Date: 2020.10.06 CISCO TECHNOLOGY INC

AI summary

In one embodiment, a process tracks measured carrier frequency offsets (CFOs) of identified transmitters over a period of activity of the identified transmitters, and determines predicted CFOs for the identified transmitters and predicted transmitter behavior as a probability of specific transmitters of the identified transmitters being active at given times based on the activity of the identified transmitters. The process may then determine, based on the predicted CFOs and predicted transmitter behavior, CFO ranges that a receiver should expect for upcoming packets, and instructs the receiver to use the CFO ranges as a prioritized list of dynamically selected CFOs to use to extract single or colliding packets from among potential interferences using frequency demodulation.