BASE-BAND PULSE OBJECT SENSOR SYSTEM

• US 3,772,697 A
• Filed: 04/19/1971
• Issued: 11/13/1973
• Est. Priority Date: 04/19/1971
• Status: Expired due to Term

• Current Assignee: Gerald F. Ross
• Original Assignee: Gerald F. Ross
• Inventors: Ross, Gerald F.
• Primary Examiner(s): Tubbesing, T. H.
• Application Number:
  US05/134,990
• Time in Patent Office: 939 Days
• Field of Search: 343/5R,5PD,13R,17.1R
• US Class Current: 342/21
• CPC Class Codes: G01S 13/0209 Systems with very large relative bandwidth, i.e. larger than 10 %, e.g. baseband, pulse, carrier-free, ultrawideband

Abstract

A pulse transmitter-receiver system for detecting the presence and proximity of objects employs transmission of short base-band or subnanosecond electromagnetic signals and reception thereof by a dispersionless, broad band transmission line antenna system with a receiver circuit cooperating with a biased semiconductor diode located within the transmission line antenna system for instantaneously detecting substantially the total energy of each reflected base-band pulse and for providing corresponding outputs suitable for indication of the presence or of the range of such proximate objects. This system is intended to be primarily effective at distances of approximately twenty five feet or less.

Claims

1. The combination comprising:

transmitter means for transmitting base-band pulse signals toward a reflecting object, said transmitter means including;

substantially non-dispersive transmission line transmitter antenna means for propagating and radiating, without distortion, a train of said base-band pulse signals in the TEM transmission line mode, each said base-band pulse signal having a wide frequency range spectral line content, the energy in any selected one of said spectral lines being substantially below noise level, and signal generator means for exciting said transmission line antenna means, receiver means having substantially non-dispersive receiver transmission line means for receiving a signal reflected from said object, circuit means responsive to said reflected signal coupled to said receiver transmission line means for directly producing a substantially unipolar output signal of substantially greater duration than said reflected signal, means for indicating the distance to said reflecting object, said means for indicating distance comprising first and second indicator base-band propagation transmission line means having first and second respective input port means, means supplying said first input port means with base-band pulses from said signal generator means substantially synchronously with the excitation of said transmission line transmitter antenna means, and means supplying said second input port means with said substantially unipolar output signal of said circuit means responsive to said reflected signal.

2. Apparatus as described in claim 1 wherein said means for indicating distance having first and second indicator base-band propagation transmission line means comprises a plurality of discrete display elements, each display element being parallel coupled in operative spaced relation between said first and second indicator base-band transmission line means, said discrete display elements being adapted to respond to the simultaneous arrival at a predetermined one of said discrete display elements of signals applied to said respective first and second port means.

3. Apparatus as described in claim 2 wherein said display elements comprise means for generating visible light.

4. The combination comprising:

transmitter means for transmitting base-band pulse signals toward a reflecting object, said transmitter means including;

substantially non-dispersive transmission line transmitter antenna means for propagating and radiating, without distortion, a train of said base-band pulse signals in the TEM transmission line mode, each said base-band pulse signal having a wide frequency range spectral line content, the energy in any selected one of said spectral lines being substantially below noise level, and signal generator means for exciting said transmission line transmitter means, receiver means having substantially non-dispersive receiver transmission line means for receiving a signal reflected from said object, circuit means responsive to said reflected signal coupled to said receiver transmission line means for directly producing a substantially unipolar output signal of substantially greater duration than said reflected signal, and utilization means responsive to said output signal, said receiver transmission line means including automatic gain control means having;

first means controlled by said signal generator means for sampling said received signal within said receiver transmission line means in a first predetermined time interval following said transmission of each said base-band pulse signals toward said reflecting obJect, and signal attenuator means for supplying said sampled received signal to said circuit means responsive to said reflected signal.

5. The combination for sensing nearby objects comprising:

pulse generator means for generating base-band pulses each having a wide-frequency-range spectral line content, the energy in any selected one of said spectral lines being below the ambient noise level, directive transmission line antenna means responsive to said pulse generator means for radiating, substantially without distortion, said base-band pulses toward a reflecting object, directive receiver transmission line antenna means responsive to a reflected version of said train of base-band pulses for propagation therein substantially without distortion, detector circuit means directly responsive to said directive receiver transmission line antenna means for producing substantially unipolar output signals of greater amplitude than said reflected base-band pulses, and utilization means directly responsive to said detector circuit means in the presence of said reflecting object including;

direct current restorer means responsive to said detector circuit means, amplifier means responsive to said direct current restorer means, and reflecting object presence display means responsive to said amplifier means.

6. The combination for sensing range to a nearby reflecting object comprising:

pulse generator means for generating a base band pulse having a wide-frequency-range spectral-line content, the energy in any selected one of said spectral lines being below the ambient noise level, directive TEM mode transmission line antenna means responsive to said pulse generator means for radiating, substantially without distortion, said base band pulse toward said nearby reflecting object, directive receiver TEM mode transmission line antenna means responsive to a reflected version of said base band pulse for propagation therein substantially without distortion, diode detector circuit means directly responsive to said directive receiver transmission line antenna means for producing a substantially unipolar output signal of greater amplitude than said reflected base band pulses, first and second TEM mode transmission line means respectively responsive to said pulse generator means and to said diode detector circuit means, and range display means responsive to said first and second TEM mode transmission line means.

7. Apparatus as described in claim 6 wherein said range display means comprises:

a first plurality of n coupling means individually coupled at regularly spaced intervals along said first TEM mode transmission line means where n is an integer, a second plurality of n coupling means individually coupled at said regularly spaced intervals along said second TEM mode transmission line means, and first and second matched termination means for absorbing pulse signals propagating within said respective first and second TEM mode transmission lines and passing therein said respective n'"'"''"'"'th coupling means.

8. Apparatus as described in claim 7 further including at least:

first AND gate means responsive to the first coupling means of said first plurality of coupling means and to the n'"'"''"'"'th coupling means of said second plurality of coupling means, and n'"'"''"'"'th AND gate means responsive to the n'"'"''"'"'th coupling means of said first plurality of coupling means and to the first coupling means of said second plurality of coupling means, said first and n'"'"''"'"'th AND gate means comprising members of a finite plurality of n AND gate means.

9. Apparatus as described in claim 8 further including:

pulse signal amplifying means respectively responsive to one each of said n AND gate means, range indicator means responsive to said respective AND gate means for indicating the simultaneous arrival at one of said AND gate means of a pulse signal from said pulse generator means and from said diode detector circuit means.

10. Apparatus as described in claim 9 wherein said range indicator means includes:

pulse stretching means, direct current restorer means, and amplifier means.

11. The combination for sensing nearby objects comprising:

pulse generator means for generating base band pulses each having a wide-frequency-range spectral line content, the energy in any selected one of said spectral lines being below the ambient noise level, directive transmission line antenna means responsive to said pulse generator means for radiating, substantially without distortion, said base band pulses toward a reflecting object, directive receiver transmission line antenna means responsive to a reflected version of said train of base band pulses for propagation therein substantially without distortion, gain control means responsive to said directive receiver transmission line antenna means comprising first and second parallel branching transmission line means with respective input and output means, said first branching transmission line means including attenuator means and first sampling means controlled by said pulse generator means for sampling base band pulses in a first predetermined time interval following generation of each said base band pulse by said pulse generator means, said second branching transmission line means including second sampling means controlled by said pulse generator means for sampling base band pulses in a second predetermined time interval following generation of each said base band pulse by said pulse generator means, diode detector circuit means directly responsive to said output means of said gain control parallel branching transmission line means for producing substantially unipolar output signals of greater amplitude than said reflected base band pulses, and utilization means responsive to said dode detector circuit means.

12. Apparatus as described in claim 11 wherein:

said first and second sampling means comprise diode means in parallel relation in each of said branching transmission line means, and said pulse generator means controls the conductivity of said diode means for time interval control of flow of received base band pulse signals along each said branching transmission line means.