Unlock instant, AI-driven research and patent intelligence for your innovation.

System Compensation Method for Reducing Self-Interference Effects in Frequency Modulated Continuous Wave Altimeter Systems

A technology of altimeter and mixer, which is applied in the field of altimeter system, and can solve the problems of receiver mixer output signal distortion, false range determination, range error, etc.

Inactive Publication Date: 2018-01-23
HONEYWELL INT INC
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Distortion of the receiver mixer output signal, resulting in range errors, missed detection, or grossly spurious range determinations
[0003] Thus, self-interference from short-path transceiver leakage signals is a significant limiting factor for ultra-short-range performance

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • System Compensation Method for Reducing Self-Interference Effects in Frequency Modulated Continuous Wave Altimeter Systems
  • System Compensation Method for Reducing Self-Interference Effects in Frequency Modulated Continuous Wave Altimeter Systems
  • System Compensation Method for Reducing Self-Interference Effects in Frequency Modulated Continuous Wave Altimeter Systems

Examples

Experimental program
Comparison scheme
Effect test

example 1

[0057] Example 1 includes an altimeter system comprising: a receiver mixer including an antenna input and a local oscillator input; a transceiver circulator communicatively coupled to the antenna via a transmission line having a selected length and communicating ground coupled to the antenna input of the receiver mixer; and a transmitter configured to output a transmitter signal to the antenna through a transceiver circulator, wherein the transmitter signal is frequency modulated with a linear ramp, wherein the transmitter communicates with ground coupled to a receiver mixer to input a local oscillator signal at a local oscillator input of the receiver mixer, wherein the receiver mixer is communicatively coupled to input a local oscillator signal at an antenna input of the receiver mixer Input the target reflected signal from the antenna, where the target reflected signal is reflected from the target to the antenna, and where the selected length of the transmission line is set ...

example 2

[0058] Example 2 includes the altimeter system of Example 1, wherein the antenna reflection leakage signal of the transmitter signal is reflected by the antenna through the circulator to the antenna input of the receiver mixer, wherein the circulator leakage signal of the transmitter signal is reflected by the circulator transmitter from the transmitter to the antenna input of the receiver mixer, wherein the antenna reflection leakage signal and the circulator leakage signal are superimposed at the antenna input of the receiver mixer to form a composite leakage signal, and wherein, based on the transmission line For a selected length of , the 180 degree phase difference between the antenna reflection leakage signal and the circulator leakage signal occurs at frequencies outside the scan bandwidth.

example 3

[0059] Example 3 includes the altimeter system of any of Examples 1-2, wherein a phase of the local oscillator signal received at the local oscillator input of the receiver mixer is maintained in quadrature with a phase of the composite leakage signal.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention provides an altimeter system. The altimeter system includes: a receiver mixer including an antenna input and a local oscillator input; a transceiver circulator communicatively coupled to the antenna via a transmission line of a selected length and to the receiver mixer an antenna input of the transmitter; and a transmitter configured to output a transmitter signal to the antenna through the transceiver circulator. The transmitter signal is frequency modulated with a linear ramp. The transmitter is communicatively coupled to the receiver mixer to input a local oscillator signal at a local oscillator input of the receiver mixer. The receiver mixer is communicatively coupled to input a target reflected signal from the antenna at an antenna input of the receiver mixer. The selected length of the transmission line is set such that the resultant leakage signal at the antenna input of the receiver mixer has a linear phase over the sweep bandwidth.

Description

Background technique [0001] Radio altimeters for aircraft are required to measure altitude (range) from over 6000 feet to less than 4 feet. Single antenna frequency modulated continuous wave (FMCW) altimeter systems have short range limitations due to short path transceiver leakage through various paths causing self interference. The short-path transceiver leakage signal is the main result of the combined leakage signal due to the limited directivity of the transceiver circulator and the reflection of the transmitter signal from (leaving) the antenna into the receiver. The leakage signal due to the limited directivity of the transceiver circulator is referred to herein as "circulator leakage signal". The reflection of the transmitter signal from the antenna into the receiver is referred to herein as the "antenna reflection leakage signal". [0002] The superposition of the circulator leakage signal and the antenna reflection leakage signal at the receiver generates self-inte...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(China)
IPC IPC(8): H04B1/525
CPCG01S13/882G01S7/034G01S7/038G01S13/343G01S13/32G01S7/0233G01S7/023
Inventor P·D·费尔古森
Owner HONEYWELL INT INC