Bidirectional Doppler Measurement for Clock Offset Cancellation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing communication technologies fail to accurately distinguish between Doppler frequency shift caused by channel mobility and receiver-transmitter clock offset, which is crucial for sensing services that require precise Doppler information for detecting dynamic targets.
Innovation Solution
A method and apparatus that involves bidirectional exchange of measurement signals between devices to counteract the impact of receiver-transmitter clock offset by combining Doppler measurement results, allowing for accurate determination of Doppler frequency shift information associated with motion of a sensing target in a channel.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If frequency shift information is calculated based on received signal, then frequency shift compensation can be performed to meet demodulation performance, but the Doppler frequency shift caused by channel mobility cannot be distinguished from receiver-transmitter clock offset
Solution Approach 1:
The patent segments the frequency shift measurement process into two separate directional measurements: one from terminal to network device and another from network device to terminal. By dividing the measurement into separate directional components, the system can isolate and eliminate the clock offset influence, obtaining accurate Doppler frequency shift information for sensing services while maintaining demodulation performance.
Solution Approach 2:
The patent implements a feedback mechanism where the network device sends measurement signals to the terminal, the terminal measures and reports Doppler information back to the network device, and the network device uses this feedback to calculate the actual channel Doppler frequency shift by combining it with its own measurement results. This closed-loop feedback process enables accurate Doppler measurement for sensing services.
2Measurement precision
If bidirectional measurement signals are exchanged between devices, then accurate Doppler frequency shift information can be obtained by counteracting clock offset, but measurement complexity increases
Solution Approach 1:
The patent makes the measurement signals universal by using the same type of reference signal for both downlink and uplink Doppler measurements. The network device sends downlink reference signals that can be measured by the terminal, and the terminal sends uplink reference signals that can be measured by the network device. This multi-functional use of reference signals simplifies the measurement process despite the bidirectional nature.
Solution Approach 2:
The patent enables each device to perform self-measurement of Doppler frequency shift using locally generated reference signals. The terminal measures the downlink signal from the network device using its own receiver, and the network device measures the uplink signal from the terminal using its own receiver. This self-service approach reduces the need for complex coordinated measurement mechanisms.
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
This approach enables precise Doppler measurement by canceling out the influence of clock frequency offsets, thereby improving the accuracy of sensing services in environments with dynamic targets.
Implementation Method 1
Doppler frequency shift information associated with motion of a sensing target in a channel
Data Source
AI summary
A Doppler measurement method and apparatus, and a communication device, are provided. The Doppler measurement method includes: A first device obtains first information and second information. The first device obtains target information based on the first information and the second information. The first information is Doppler frequency shift information obtained by a third device by measuring a first signal sent by a second device. The second information is Doppler frequency shift information obtained by the second device by measuring a second signal sent by the third device. The target information is used for indicating Doppler frequency shift information between the second device and the third device. The Doppler frequency shift information is Doppler frequency shift information associated with motion of a sensing target in a channel.