BLE Preamble Detection Power Mode Switching

Solution Overview

Problem

Bluetooth Low Energy (BLE) devices face high power consumption during scanning due to frequent channel scans, leading to potential packet reception errors when switching from low power mode to high power mode, especially if the transition occurs during access address or payload receipt, which can result in non-compliance with BLE protocols.

Innovation Solution

Implementing a method where BLE devices switch from a low power mode to a high power mode upon detecting the preamble of an incoming packet, allowing for accurate packet processing without impacting the reception of the access address and payload, by utilizing a preamble detection algorithm to timing the switch before the access address arrives.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If the receiver switches from low power mode to high power mode during packet reception, then packet processing accuracy is improved, but packet reception errors increase due to noise during transition

Engineering Contradiction:

Improvepacket processing accuracyVSAvoidpacket reception error rate

Core Design Contradiction:

Measurement precisionVSReliability

Solution Approach 1:

The receiver performs a warm-up period in high power mode before actual packet reception begins. This preliminary action allows the receiver to stabilize and reduce noise before critical packet data is received, thereby maintaining high processing accuracy without introducing reception errors during the transition phase

Inventive Principle:

Principle #10Preliminary action

2Reliability

If the receiver operates in high power mode continuously during scanning, then packet reception reliability is improved, but power consumption increases

Engineering Contradiction:

Improvepacket reception reliabilityVSAvoidpower consumption

Core Design Contradiction:

ReliabilityVSUse of energy by moving object

Solution Approach 1:

The receiver alternates between low power mode and high power mode in periodic cycles. During low power mode, the receiver conserves energy while in high power mode, it performs warm-up and receives packets. This periodic switching maintains adequate packet reception reliability while significantly reducing average power consumption compared to continuous high power operation

Inventive Principle:

Principle #19Periodic action

Solution Approach 2:

The receiver performs a warm-up period in high power mode before actual packet reception begins. This preliminary action allows the receiver to stabilize and reduce noise before critical packet data is received, thereby maintaining high processing accuracy without introducing reception errors during the transition phase

Inventive Principle:

Principle #10Preliminary action

3Measurement precision

If the receiver switches from low power mode to high power mode before packet arrival, then packet reception accuracy is improved, but the timing precision required increases

Engineering Contradiction:

Improvepacket reception accuracyVSAvoidtiming synchronization difficulty

Core Design Contradiction:

Measurement precisionVSDifficulty of detecting and measuring

Solution Approach 1:

The receiver performs a warm-up period in high power mode before actual packet reception begins. This preliminary action allows the receiver to stabilize and reduce noise before critical packet data is received, thereby maintaining high processing accuracy without introducing reception errors during the transition phase

Inventive Principle:

Principle #10Preliminary action

Data Source

PatentUS11330468B2Low power techniques for bluetooth low energy in scanning state

Publication Date: 2022.05.10 QUALCOMM INC

AI summary

This disclosure provides systems, devices, apparatus, and methods, including computer programs encoded on storage media, related to low power techniques for a BLE device during a scanning state. The BLE device is configured to scan for a preamble of a packet while in a first power mode and detect when a bit of the preamble is received. Upon detecting that the bit of the preamble is received, the BLE device switches from the first power mode to a second power having a higher operating power for the BLE device than the first power mode. The switch in power modes occurs while the preamble is being received or immediately after the preamble is received and before an access address of the packet is received. The BLE device, while in the second power mode, then scans for the access address of the packet.