Bluetooth Packet Spoofing for LTE Coexistence Interference
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The integration of multiple wireless communication technologies in a single device, such as smartphones, often results in adjacent channel interference due to overlapping frequency bands, significantly degrading performance for both the device and connected base stations.
Innovation Solution
The implementation of a Bluetooth transceiver that spoofs the packet type of Bluetooth ACL packets based on LTE schedule information to shift the arrival time of reply packets away from LTE signal reception, minimizing interference by aligning Bluetooth transmissions with LTE uplink and downlink time slots.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If multiple wireless communication technologies (LTE and Bluetooth) are integrated in a single device, then device functionality and communication versatility are improved, but adjacent channel interference between the technologies worsens
Solution Approach 1:
The Bluetooth transmission schedule is segmented into multiple time slots, with different packet types assigned to different slot positions. The system divides the transmission opportunities into first time slots for initial ACL packets and second time slots for reply packets, separating interference-prone transmissions in time domain
Solution Approach 2:
The system implements periodic transmission schedules where Bluetooth ACL packets are sent at specific intervals aligned with LTE frame structures. By periodically transmitting at scheduled intervals and using repeating patterns of time slot assignments, the system creates predictable interference patterns that can be managed through the spoofing mechanism
2Productivity
If Bluetooth transmissions are allowed to proceed according to normal scheduling, then Bluetooth communication efficiency is improved, but interference with LTE signal reception worsens
Solution Approach 1:
The system performs preliminary scheduling of Bluetooth transmissions by determining the number of time slots in advance based on packet type. The spoofed packet type field is set beforehand to indicate a larger number of time slots than actually needed, pre-allocating transmission windows that are then strategically positioned to avoid LTE downlink reception periods
Solution Approach 2:
The system changes the packet type parameter in the Bluetooth ACL packet header to spoof a larger duration. By modifying this parameter field to indicate extended transmission time, the system alters the scheduling behavior to allocate more time slots, which are then used to shift the reply packet transmission to interference-free time windows
3Productivity
If the number of Bluetooth time slots is increased to accommodate more transmissions, then Bluetooth throughput is improved, but the duration of transmission periods increases causing more interference opportunities
Solution Approach 1:
The system dynamically adjusts the apparent transmission duration by spoofing packet type based on the actual content and priority of data. Rather than using fixed time slot allocations, the system flexibly modifies the packet type field to create variable-length transmission windows that adapt to LTE schedule conditions, allowing efficient use of time slots while avoiding extended interference periods
Data Source
AI summary
A wireless device including a first transceiver to communicate according to a first schedule using a first communication protocol. The first schedule includes information of uplink and downlink slots. A second transceiver communicates according to a second schedule using a second communication protocol. The second schedule includes a first number of slots for transmitting packets. A scheduler changes, based on the first schedule, the first number of slots to a second number of slots. The second number of slots is greater than the first number of slots. A packetizer selects a packet type of a first packet for transmission from the first transceiver to a remote device. The packet type indicates that the first packet requires the second number of slots for transmission and shifts transmission of a response from the remote device to one of the downlink slots to minimize interference between communications of the first and second transceivers.