Radar Phase-Shift Keying for Doppler Peak Separation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Radar devices using MIMO techniques face challenges in accurately separating transmission signals from multiple antennas due to aliased noise and overlapping peaks on the Doppler frequency axis, especially when multiple objects are present, leading to reduced accuracy in velocity estimation and angle measurement.
Innovation Solution
The radar device employs a transmitting antenna unit with multiple antennas, an oscillator, a modulator, and a processor that executes phase-shift keying using a linear cyclic block code to generate distinct signal components on the Doppler frequency axis, ensuring that peaks corresponding to different transmission signals have unique spacings, thereby reducing overlapping and improving signal separation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If phase-shift keying is applied to separate transmission signals from multiple antennas, then signal separation capability is improved, but overlapping peaks and aliased noise occur on the Doppler frequency axis when multiple objects are present
Solution Approach 1:
The patent changes the parameter of phase rotation amounts to be non-uniformly distributed across the Doppler frequency axis. Specifically, it assigns different phase rotation amounts to different transmitting antennas such that the spacing between peaks corresponding to different transmission signals is unique, preventing peak overlap and aliased noise when multiple objects are present.
2Measurement precision
If the number of phases is increased to avoid peak overlapping, then signal separation accuracy is improved, but device complexity and implementation difficulty increase
Solution Approach 1:
The patent applies partial action by using a limited number of phases (specifically, the number of phases is equal to the number of transmitting antennas) while achieving effective signal separation. Instead of requiring a large number of phases to avoid overlapping, it strategically assigns phase rotation amounts to create unique peak spacings with the given number of phases, thereby avoiding the need for excessive phases.
3Measurement precision
If multiple transmitting antennas are used to improve resolution, then radar resolution is improved, but difficulty in separating transmission signals increases
Solution Approach 1:
The patent applies local quality by assigning different phase rotation amounts to different transmitting antennas based on their specific positions and functions. Each transmitting antenna is given a unique phase rotation amount that creates distinct peak spacings on the Doppler frequency axis, making it easier to identify and separate signals from each antenna even when multiple objects are present.
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 allows for accurate estimation of object velocity and angle measurement even in the presence of multiple objects, simplifying implementation by reducing the number of required phases and minimizing overlapping peaks, thus enhancing the reliability of signal separation.
Implementation Method 1
The modulator generates multiple transmission signals respectively provided to the multiple transmitting antennas by executing phase-shift keying. The phase-shift keying includes: diverging the common signal into multiple diverged signals having a number being equal to the number of the multiple transmitting antennas; and rotating respective phases of the multiple diverged signals by different amounts of phase rotation.
Implementation Method 2
a receiving antenna unit, and a processor. The receiving antenna unit includes at least one receiving antenna. The receiver generates a received code of at least one received signal received by the receiving antenna unit.
Implementation Method 3
The receiver generates a received code of at least one received signal received by the receiving antenna unit. The received code is acquired by encoding an appearance pattern of a peak of at least one received signal on a Doppler frequency axis.
Data Source
AI summary
A radar device includes a transmitting antenna unit, a modulator, a receiving antenna unit, a receiver, and a processor. The transmitting antenna unit includes transmitting antennas. The modulator generates transmission signals respectively provided to the transmitting antennas by executing phase-shift keying through diverging the common signal into diverged signals having the number being equal to the number of the transmitting antennas and rotating respective phases of the diverged signals. The receiving antenna unit includes at least one receiving antenna. The receiver generates a received code of at least one received signal. The received code is acquired by encoding an appearance pattern of a peak of at least one received signal on a Doppler frequency axis. The processor generates information related to an object, according to the received code generated by the receiver. The modulator executes the phase-shift keying by using a linear block code as an assigned code.