Ethernet connection of airborne radar over fiber optic cable

• US 7,158,072 B1
• Filed: 09/08/2006
• Issued: 01/02/2007
• Est. Priority Date: 09/08/2006
• Status: Active Grant

• Current Assignee: Rockwell Collins, Inc. (Rtx Corporation)
• Original Assignee: Rockwell Collins, Inc. (Rtx Corporation)
• Inventors: Andreatta, Ronald W., Venkatachalam, Ranganath
• Primary Examiner(s): Gregory; Bernarr E.
• Application Number:
  US11/517,913
• Time in Patent Office: 116 Days
• Field of Search: 398/135, 398/140, 398/141, 244/3.1, 244/3.11, 244/3.13, 244 315- 318, 342 13- 16, 342 25 R- 26 D, 342 52- 60, 342 82-103, 342175-186, 342/195
• US Class Current: 342/26.00B
• CPC Class Codes: G01S 13/953 mounted on aircraft
• CPC Class Codes: G01S 7/003 Transmission of data between radar, sonar or lidar systems and remote stations
• CPC Class Codes: Y02A 90/10 Information and communication technologies [ICT] supporting adaptation to climate change, e.g. for weather forecasting or climate simulation

Abstract

A weather radar signal path for an aircraft. The signal path has an antenna, a digital down-converter, a first transceiver, fiber optic cabling, a second transceiver and a processing unit. The antenna is adapted to, in a first mode, receive reflected radar signals from atmosphere ahead. The digital down-converter is adapted to convert the reflected radar signals received by the antenna into digital radar signals at a lower frequency. The first transceiver is adapted to, in the first mode, at least transmit the digital radar signals through said fiber optic cabling. The fiber optic cabling is adapted to, in the first mode, transfer the digital radar signals between the first and second transceivers. The second transceiver is adapted to, in the first mode, receive said digital radar signals from the fiber optic cabling. The processing unit is adapted to, in the first mode, process the digital radar signals to generate weather information based on predetermined algorithm.

Claims

1. A weather radar signal path for an aircraft, comprising:

an antenna (105), a digital down-converter (120, 121), a first transceiver (126), fiber optic cabling (125), a second transceiver (135) and a processing unit (130), WHEREIN,

said antenna is adapted to, in a first mode, receive reflected radar signals from atmosphere ahead,

said digital down-converter is coupled to said antenna, said digital down-converter is adapted to convert said reflected radar signals received by said antenna into digital radar signals at a lower frequency,

said first transceiver is coupled to said digital down-converter, said first transceiver is adapted to, in said first mode, at least transmit said digital radar signals through said fiber optic cabling,

said fiber optic cabling is coupled between said first transceiver and said second transceiver, said fiber optic cabling is adapted to, in said first mode, transfer said digital radar signals between said first and second transceivers,

said second transceiver is coupled to said fiber optic cabling, said second transceiver is adapted to, in said first mode, receive said digital radar signals from said fiber optic cabling,

said processing unit is coupled to said second transceiver, said processing unit is adapted to, in said first mode, process said digital radar signals to generate weather information based on predetermined algorithm.

2. The weather radar signal path of claim 1, further comprising:

a waveguide (110) coupled to said antenna and said digital down-converter, said waveguide being adapted to transfer said reflected radar signals from said antenna to said digital down-converter.

3. The weather radar signal path of claim 2, further comprising:

a first network unit coupled to said first transceiver, being adapted to, in said first mode, packetize and encode said digital radar signals for transmission by said first transceiver to said fiber optic cabling;

a second network unit coupled to said second transceiver, being adapted to, in said first mode, decode said digital radar signals received by said second transceiver from said fiber optic cabling,

wherein said first and second network units handle said digital radar signals according to a predetermined network protocol.

4. The weather radar signal path of claim 1, further comprising:

a first network unit coupled to said first transceiver, being adapted to, in said first mode, packetize and encode said digital radar signals for transmission by said first transceiver to said fiber optic cabling;

a second network unit coupled to said second transceiver, being adapted to, in said first mode, decode said digital radar signals received by said second transceiver from said fiber optic cabling,

wherein said first and second network units handle said digital radar signals according to a predetermined network protocol.

5. The weather radar signal path of claim 4, wherein said digital radar signals are formatted as UDP/IP datagrams.

6. The weather radar signal path of claim 4, wherein:

said processing unit is adapted to, in a second mode, generate control commands to operate said antenna,

said second transceiver is adapted to, in said second mode, transmit said control commands from said processing unit to said first transceiver through said fiber optic cabling,

said first transceiver is adapted to, in said second mode, forward said control command to said antenna.

7. The weather radar signal path of claim 1, further comprising:

additional detection sensor (207) and a second fiber optic cabling,

wherein said additional detection sensor is adapted to detect the presence of a predetermined occurrence, said additional detection sensor is coupled to said processing unit through said second fiber optic cabling.

8. A weather radar signal path for communication between an antenna and a processing unit of an aircraft, said signal path comprising:

an analog-digital converter (“

ADC”

), a digital down-converter (“

DDC”

), a digital signal processor (“

DSP”

), a first Ethernet unit, a first optical transceiver, fiber optic cabling, a second optical transceiver, and a second Ethernet unit, WHEREIN,

said ADC, coupled between said antenna and said DDC, is adapted to convert received radar signals from said antenna into digital signals,

said DDC is adapted to convert said digital signals to baseband digital signals,

said DSP is adapted to, in a first mode, direct said first Ethernet unit to encode said baseband digital signals for transmission by said first optical transceiver to said fiber optic cabling,

said second optical transceiver is adapted to, in said first mode, receive said baseband digital signals from said fiber optic cabling,

said second Ethernet unit is adapted to, in said first mode, decode said received baseband digital signals for further processing by said processing unit.

9. The weather radar signal path of claim 8, wherein:

said second Ethernet unit and said second optical transceiver are adapted to, in a second mode, encode and transmit control commands issued by said processing unit to said fiber optic cabling,

said fiber optic cabling is adapted to, in said second mode, transfer said control commands to said first optical receiver,

said first Ethernet unit and said first optical transceiver are adapted to, in said second mode, receive and decode said control commands from said fiber optic cabling,

said DSP is adapted to, in said second mode, generate instructions to operate said antenna based on said control commands received from said first Ethernet unit and said first optical transceiver.

10. The weather radar signal path of claim 9, wherein said fiber optic cabling are adapted to transfer signals in UDP/IP datagram format.

11. The weather radar signal path of claim 8, wherein said fiber optic cabling are adapted to transfer signals in UDP/IP datagram format.

12. The weather radar signal path of claim 11, wherein said DDC comprises:

a IQ sample unit adapted to convert digital signals from said ADC to in-phase and out-of-phase quadrature samples;

a filter adapted to filter said samples from said IQ sample unit using a cascaded integrator-comb filter and a finite impulse response filter;

a decimation unit coupled to said filter, being adapted to decimate said samples to baseband signals;

a gain control adapted to amplify said baseband signals;

a formatting unit adapted to format said baseband signals into streams of digital words for said DSP.

13. The weather radar signal path of claim 8, further comprising:

an additional detection sensor and a second fiber optic cabling,

wherein said additional detection sensor is adapted to detect a predetermined event and generate digital signals representative of the detection, and said second fiber optic cabling is adapted to transmit said digital signals to said processing unit for analysis.

14. A method of conducting a weather radar signal path for an aircraft, the method comprising:

receiving, using an antenna, in a first mode, reflected radar signals from atmosphere ahead;

converting, using a digital down-converter, said reflected radar signals received by said antenna into digital radar signals at a lower frequency;

transmitting, using a first transceiver, in said first mode, to transmit said digital radar signals through said fiber optic cabling;

transferring, through fiber optic cabling, in said first mode, said digital radar signals from said first transceiver;

receiving, using a second transceiver, in said first mode, said digital radar signals from said fiber optic cabling;

processing, using a processing unit, in said first mode, said digital radar signals to generate weather information based on predetermined algorithm.

15. The method of claim 14, further comprising:

transferring, using a waveguide (110) coupled to said antenna and said digital down-converter, said reflected radar signals from said antenna to said digital down-converter.

16. The method of claim 15, further comprising:

packetizing and encoding, using a first network unit, in said first mode, said digital radar signals for transmission by said first transceiver to said fiber optic cabling;

decoding, using a second network unit, in said first mode, said digital radar signals received by said second transceiver from said fiber optic cabling;

wherein said first and second network units handle said digital radar signals according to a predetermined network protocol.

17. The method of claim 14, further comprising:

packetizing and encoding, using a first network unit, in said first mode, said digital radar signals for transmission by said first transceiver to said fiber optic cabling;

decoding, using a second network unit, in said first mode, said digital radar signals received by said second transceiver from said fiber optic cabling;

wherein said first and second network units handle said digital radar signals according to a predetermined network protocol.

18. The method of claim 17, wherein said digital radar signals are formatted as UDP/IP datagrams.

19. The method of claim 17, wherein:

said processing unit also generates control commands to operate said antenna,

said second transceiver is adapted to, in said second mode, transmit said control commands from said processing unit to said first transceiver through said fiber optic cabling,

said first transceiver is adapted to, in said second mode, forward said control command to said antenna.

20. The method of claim 14, further comprising:

detecting the presence of a predetermined event;

communicating the detection to said processing unit through a second fiber optic cabling.