Large relative bandwidth radar

• US 4,651,152 A
• Filed: 09/26/1983
• Issued: 03/17/1987
• Est. Priority Date: 09/26/1983
• Status: Expired due to Fees

• Current Assignee: Geophysical Survey Systems, Inc.
• Original Assignee: Geophysical Survey Systems, Inc.
• Inventors: Harmuth, Henning F.
• Primary Examiner(s): Tubbesing, T. H.
• Assistant Examiner(s): Barron, Jr., Gilberto
• Application Number:
  US06/535,678
• Time in Patent Office: 1,268 Days
• Field of Search: 343/5 PD, 343/17.1 R, 343/18 R, 343/18 A, 343/18 B, 343/18 E, 343/17.1 PW, 343/5 R, 343/55 A, 343/17.2 R
• US Class Current: 342/13
• CPC Class Codes: G01S 13/0209 Systems with very large relative bandwidth, i.e. larger than 10 %, e.g. baseband, pulse, carrier-free, ultrawideband
• CPC Class Codes: G01S 13/04 Systems determining presence of a target based on relative movement of target G01S13/56

Abstract

A method of detecting an object that may be coated with material for preventing or attenuating reflections of incident electromagnetic waves is disclosed in which pulses of electromagnetic wave energy are generated with a large relative bandwidth in the band from about 0.1 GHz to about 12.0 GHz. Preferably, the generated pulses have a pulse duration in the range from 0.1 nanosecond to 1 nanosecond. Those pulses of electromagnetic wave energy are directed toward the object and reflections of those pulses of electromagnetic wave energy which are incident on the object are detected by receiving apparatus. The method enables coated objects to be differentiated from uncoated objects.

Claims

1. A method of detecting an object that may be coated with material for preventing or attenuating reflections of incident electromagnetic wave energy comprising the steps of

(i) generating pulses of electromagnetic wave energy whose relative bandwidth is greater than 0.85 in the band from about 0.1 GHz to about 12.0 GHz,

(ii) directing those pulses of electromagnetic wave energy toward the object, and

(iii) detecting reflections from said object of those pulses of electromagnetic wave energy which are incident on the object.

2. The method according to claim 1 wherein

in step (i) at least some of the pulses are generated with a pulse duration in the range from 1 to 0.1 nanosecond.

3. The method according to claim 2, wherein

in step (ii) at least some of the pulses directed toward the object are carrier-free pulses.