DIGITAL RADAR OR SONAR APPARATUS

• US 20140320336A1
• Filed: 12/30/2013
• Published: 10/30/2014
• Est. Priority Date: 08/31/2007
• Status: Active Grant

• Current Assignee: Flir Belgium BVBA (Teledyne Technologies Incorporated)
• Original Assignee: Raymarine UK Limited (Teledyne Technologies Incorporated)
• Inventors: Jales, Richard, Lawrence, Andrew, Maindrou, Matthieu
• Granted Patent: US 9,024,816 B2
• Time in Patent Office: Days
• US Class Current: 342/195
• CPC Class Codes: G01S 13/10 using transmission of interrupted, pulse modulated waves determination of distance by phase measurement G01S13/32
• CPC Class Codes: G01S 13/106 using transmission of pulses having some particular characteristics G01S13/12, G01S13/22, G01S13/24, G01S13/26, G01S13/28 and G01S13/30 take precedence
• CPC Class Codes: G01S 13/89 for mapping or imaging
• CPC Class Codes: G01S 15/102 using transmission of pulses having some particular characteristics
• CPC Class Codes: G01S 15/89 for mapping or imaging
• CPC Class Codes: G01S 7/062 in which different colours are used
• CPC Class Codes: G01S 7/282 Transmitters
• CPC Class Codes: G01S 7/285 Receivers
• CPC Class Codes: G01S 7/292 Extracting wanted echo-signals
• CPC Class Codes: G01S 7/34 Gain of receiver varied automatically during pulse-recurrence period, e.g. anti-clutter gain control
• CPC Class Codes: G01S 7/526 Receivers
• CPC Class Codes: G01S 7/5273 using digital techniques
• CPC Class Codes: G01S 7/529 Gain of receiver varied automatically during pulse-recurrence period for seismic signals G01V1/245
• CPC Class Codes: G01S 7/62 Cathode-ray tube displays
• CPC Class Codes: G01S 7/6263 in which different colours are used

Abstract

A radar or sonar system amplifies the signal received by an antenna of the radar system or a transducer of the sonar system is amplified and then subject to linear demodulation by a linear receiver. There may be an anti-aliasing filter and an analog-to-digital converter between the amplifier and the linear receiver. The system may also have a digital signal processor with a network stack running in the processor. That processor may also have a network interface media access controller, where the system operates at different ranges, the modulator may produce pulses of two pulse patterns differing in pulse duration and inter-pulse spacing, those pulse patterns are introduced and used to form two radar images with the two images being derived from data acquired in a duration not more than twenty times larger than the larger inter-pulse spacing, or for a radar system, larger than one half of the antenna resolution time. One or more look-up tables may be used to control the amplifier. The radar system may generate digital output which comprises greater than eight levels of radar video.

Claims

1. A radar apparatus comprising:

a modulator for generating a sequence of pulse signals;

a transmitter for converting the sequence of pulse signals to radar signals;

an antenna for emitting the radar signals and receiving return signals;

an amplifier for amplifying the return signals,

a switching device for switchedly interconnecting the transmitter to the antenna and the antenna to the amplifier;

and

a signal processor processing the amplified return signals for display and/or analysis,

characterised in that;

the radar apparatus further includes a linear receiver between the amplifier and the signal processor, the linear receiver including a linear demodulator generating a digital output representing said amplified return signals for processing by the signal processor.