Bistatic SAR Phase Synchronization via Shared Carrier Frequency

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Bistatic Synthetic Aperture Radar (BiSAR) systems face increased design complexity and low phase compensation accuracy due to different time sequences and carrier frequencies in signal transmission and reception between master and slave satellites.

Innovation Solution

The method involves transmitting and receiving radar signals and phase synchronization signals with the same carrier frequency, reducing the need for scale transformation and improving phase compensation accuracy by synchronizing phases between the two satellites.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If different carrier frequencies are used for radar signals and phase synchronization signals, then signal transmission can be separated, but the design complexity of the radar system increases

Engineering Contradiction:
Improvesignal transmission reliabilityVSAvoidradar system design complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent merges the radar signal and phase synchronization signal into the same carrier frequency band, allowing both signals to be transmitted simultaneously without requiring separate frequency allocations. This combining approach eliminates the need for complex frequency management and signal separation mechanisms, thereby reducing system design complexity while maintaining reliable signal transmission through proper signal processing techniques.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The radar system is designed to handle multiple functions (radar imaging and phase synchronization) within a single carrier frequency channel. The receiving end can distinguish between radar signals and synchronization signals through their respective modulation characteristics and processing algorithms, enabling one frequency channel to serve multiple purposes and reducing overall system complexity.

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Reliability

If different time sequences are used for transmitting radar signals and phase synchronization signals, then signal interference is avoided, but the opening time of signal receiving window increases

Engineering Contradiction:
Improvesignal transmission reliabilityVSAvoidsignal receiving window opening time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The patent enables continuous transmission of both radar signals and phase synchronization signals without time gaps or sequential switching. By using the same carrier frequency and implementing simultaneous transmission, the system maintains continuous operation for both signal types, eliminating the need to open the receiving window for extended periods to capture signals transmitted at different times, thus reducing time loss.

Inventive Principle:
Principle #20Continuity of useful action

3Adaptability or versatility

If scale transformation is performed on phase synchronization signals, then frequency differences are compensated, but phase compensation accuracy decreases

Engineering Contradiction:
Improvefrequency compatibilityVSAvoidphase compensation accuracy
Core Design Contradiction:
Adaptability or versatilityVSMeasurement precision

Solution Approach 1:

Instead of performing scale transformation on the phase synchronization signals, the patent changes the fundamental parameter approach by transmitting both radar and synchronization signals at the same carrier frequency from the outset. This eliminates the need for post-reception frequency scaling and transformation operations, thereby preserving phase compensation accuracy while still achieving frequency compatibility between the master and slave satellites.

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP3865908B1Bistatic SAR phase synchronization signal processing method and device
Publication Date: 2022.12.28 INST OF ELECTRONICS CHINESE ACAD OF SCI
  • EP3865908B1 patent drawingFigure 1~2
  • EP3865908B1 patent drawingFigure 3
  • EP3865908B1 patent drawingFigure 4

AI summary

The present application provides a Bistatic SAR phase synchronization signal processing method and device based on carrier frequency signals. The method includes: transmitting, by a first radar in the same pulse period, a radar signal to a target object, and a first phase synchronization signal to a second radar, wherein the carrier frequency of the radar signal is the same as that of the first phase synchronization signal; receiving, by the first radar, a second phase synchronization signal transmitted by the second radar; and performing phase synchronization compensation on the received signal of the second radar at least according to the first phase synchronization signal and the second phase synchronization signal.