Bluetooth LTE Coexistence via Time Division Multiplexing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Bluetooth and LTE/WiMax technologies face coexistence issues due to their adjacent frequency bands, causing mutual interference, which prevents simultaneous operation.
Innovation Solution
A communication unit with a processor that synchronizes Bluetooth transactions with LTE frames using a legacy command, such as a role switch command, to align Bluetooth network clock with LTE frames, allowing simultaneous transmission and reception without interference.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If Bluetooth and LTE/WiMax operate in adjacent frequency bands simultaneously, then both technologies can be used together, but mutual interference occurs preventing coexistence
Solution Approach 1:
The patent implements Time Division Multiplexing (TDM) where Bluetooth and LTE/WiMax transmissions are divided into periodic time slots. Each technology is activated in specific alternating intervals, ensuring that when one transmits, the other remains silent. This periodic scheduling eliminates mutual interference while maintaining the ability to operate both technologies, directly resolving the technical contradiction between versatility and interference.
2Reliability
If Bluetooth transactions wait for natural synchronization to LTE frames, then timing alignment occurs, but communication delay increases
Solution Approach 1:
The patent employs a Time Advance (TA) mechanism where the User Equipment (UE) proactively adjusts its Bluetooth transmission timing based on pre-calculated synchronization parameters from LTE frames. Instead of waiting for natural drift-based synchronization, the UE applies a TA offset in advance to align Bluetooth transmissions with upcoming LTE frame boundaries. This preliminary timing adjustment achieves reliable synchronization while minimizing communication delay.
3Reliability
If Bluetooth network clock drifts for a long period to synchronize, then timing alignment with LTE is achieved, but synchronization time increases
Solution Approach 1:
The patent changes the timing parameter of Bluetooth transmissions by applying a Time Advance (TA) offset to the Bluetooth network clock. Instead of allowing the clock to drift naturally over a long period, the system calculates the required TA value based on LTE frame timing and adjusts the Bluetooth transmission timing parameter directly. This parameter change achieves rapid synchronization within a single frame period rather than requiring extended drift compensation.
Data Source
AI summary
A communication unit has BT and LTE transceivers, and a BT processor. The BT processor sets up a BT connection over the BT transceiver; performs a legacy command to synchronize BT transactions over the BT connection based on LTE frames in a LTE connection over the LTE transceiver, so that a BT network clock is synchronized to LTE frames. The legacy command is a role switch command that is used to set a BT alignment time of a switch point between Bluetooth master/slave packets to a LTE switch between transmit and receive; and is specified in a BT Core Specification 4.0 or earlier. The processor can determine an expected alignment time to align BT master and slave packets to transmit and receive in the LTE frame based on a start time of the LTE frame, and can indicate the expected alignment time in the legacy command.