Phase-Based Ranging With Oscillator Sleep and Phase Tracking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing phase-based ranging methods for low-power radio transceivers require continuous operation of local oscillators, leading to increased power consumption and reduced battery life.
Innovation Solution
A method and system that deactivate the local oscillator between signal transmissions and use a phase tracking module to maintain phase coherence by digitally tracking the local oscillator phase before and after reactivation, allowing power savings while maintaining accurate phase measurements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the local oscillator is kept continuously active during quick tone exchange, then phase coherence is maintained, but power consumption increases significantly
Solution Approach 1:
The local oscillator is activated periodically only during the brief quick tone exchange intervals rather than continuously. The oscillator is turned on to generate CW signals for phase measurement, then turned off during idle periods, achieving periodic operation that reduces average power consumption while maintaining measurement capability when needed
Solution Approach 2:
Phase tracking is performed in advance by measuring and storing the phase of the local oscillator before deactivation. This preliminary phase measurement allows the system to compensate for phase changes after reactivation, ensuring measurement accuracy is maintained despite the oscillator being off during idle periods
2Use of energy by moving object
If the local oscillator is deactivated between transmissions, then power consumption is reduced, but phase coherence is lost
Solution Approach 1:
A phase tracking module continuously monitors and measures the phase of the local oscillator signal. This feedback mechanism provides phase information that is stored and used to compensate for phase changes when the oscillator is reactivated, ensuring phase coherence is restored and maintained despite periodic deactivation
Solution Approach 2:
The phase tracking module acts as an intermediary that bridges the gap between oscillator deactivation and reactivation. It captures phase information before shutdown and applies compensation after restart, mediating the transition and maintaining phase coherence without requiring the oscillator to remain continuously active
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Reduces power consumption by up to 10mA during quick tone exchange, enabling efficient phase-based ranging with minimal impact on measurement accuracy.
Implementation Method 1
generate continuous wave (CW) signals at different frequencies
Implementation Method 2
The LO generator generates an LO signal used for frequency downconversion and is periodically powered on and off. The phase detector detects the phase of the LO signal when the LO generator is powered on based on the phase of the down-converted signal.
Implementation Method 3
Phase-based measurements may be used to measure distance by estimating the phase rotations induced by propagation of a signal
Data Source
Figure 1~2
Figure 3
Figure 4~5
AI summary
The disclosure relates to determining a carrier phase shift between a first transceiver (101) and a second transceiver (103), each transceiver comprising a local oscillator for generating a carrier signal, an example method for which comprises: the first transceiver (101) generating and transmitting a first continuous wave carrier signal packet (201); the second transceiver (103) receiving the first continuous wave carrier signal packet (201); the second transceiver (103) calculating a first phase correction (PCTB) based on a comparison between the received first continuous wave carrier signal packet (201) and a local oscillator carrier signal at the second transceiver (103); the second transceiver (103) generating and transmitting a second continuous wave carrier signal packet (203); the first transceiver (101) receiving the second continuous wave carrier signal packet (203); the first transceiver (101) calculating a second phase correction (PCTA) based on a comparison between the received second continuous wave carrier signal packet (203) and a local oscillator signal at the first transceiver (101); and the first transceiver (101) calculating the carrier phase shift (θ1W) from an average of the first and second phase corrections (PCTB, PCTA), wherein the local oscillator of the first transceiver (101) is deactivated after transmitting the first continuous wave carrier signal packet (201) and reactivated after a time period (301) before receiving the second continuous wave carrier signal packet (203).