Scanning ultra wideband impulse radar

• US 7,884,757 B2
• Filed: 10/18/2007
• Issued: 02/08/2011
• Est. Priority Date: 10/18/2007
• Status: Active Grant

• Current Assignee: TiaLinx, Inc.
• Original Assignee: TiaLinx, Inc.
• Inventors: Niktash, Afshin, Mohamadi, Farrokh
• Primary Examiner(s): Gregory; Bernarr E
• Application Number:
  US11/874,414
• Publication Number:
  US 20090102703A1
• Time in Patent Office: 1,209 Days
• Field of Search: 342/21, 342 73- 81, 342/118, 342/128, 342130-147, 342/158, 342/175, 342200-204, 342368-377, 342385-387, 342/22, 342/67, 342/27, 342/28, 342 82-103, 342/157, 342192-197, 343/700.MS, 343/700.R, 343/850, 343/853, 375130-153
• US Class Current: 342/175
• 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 13/426 Scanning radar, e.g. 3D radar G01S13/66 takes precedence
• CPC Class Codes: G01S 13/86 Combinations of radar systems with non-radar systems, e.g. sonar, direction finder
• CPC Class Codes: G01S 13/888 through wall detection
• CPC Class Codes: G01S 2013/0254 Active array antenna
• CPC Class Codes: G01S 7/003 Transmission of data between radar, sonar or lidar systems and remote stations
• CPC Class Codes: G01S 7/2926 by integration
• CPC Class Codes: H01Q 21/065 Patch antenna array
• CPC Class Codes: H01Q 3/02 using mechanical movement of antenna or antenna system as a whole
• CPC Class Codes: H01Q 3/26 varying the relative phase or relative amplitude of energisation between two or more active radiating elements; varying the distribution of energy across a radiating aperture H01Q3/12, H01Q3/22, H01Q3/24 take precedence

Abstract

In one embodiment, an ultra wide band (UWB) radar includes: a substrate; a plurality of antennas adjacent the substrate, the plurality of antennas being arranged into a plurality of sub-arrays; an RF feed network adjacent the substrate, the RF feed network coupling to a distributed plurality of amplifiers integrated with the substrate, wherein the RF feed network and the distributed plurality of amplifiers are configured to form a resonant network such that if a timing signal is injected into an input port of the RF feed network, the resonant network oscillates to provide a globally-synchronized RF signal across the network; a plurality of pulse-shaping circuits corresponding to the plurality of sub-arrays, each pulse-shaping circuit being configured to receive the globally-synchronized RF signal from the network and process the globally-synchronized RF signal into pulses for transmission through the corresponding sub-array of antennas; and an actuator for mechanically scanning the UWB radar so that the pulses transmitted by the antennas scan across a desired area.

Claims

1. An ultra wide band (UWB) radar, comprising:

a substrate;

a plurality of antennas adjacent the substrate, the plurality of antennas being arranged into a plurality of sub-arrays;

an RF feed network adjacent the substrate, the RF feed network coupling to a distributed plurality of amplifiers integrated with the substrate, wherein the RF feed network and the distributed plurality of amplifiers are configured to form a resonant network such that if a timing signal is injected into an input port of the RF feed network, the resonant network oscillates to provide a globally-synchronized RF signal across the network;

a plurality of pulse-shaping circuits corresponding to the plurality of sub-arrays, each pulse-shaping circuit being configured to receive the globally-synchronized RF signal from the network and process the globally-synchronized RF signal into pulses for transmission through the corresponding sub-array of antennas; and

an actuator for mechanically scanning the UWB radar so that the pulses transmitted by the antennas scan across a desired area.

2. The UWB radar of claim 1, wherein the substrate comprises a semiconductor wafer.

3. The UWB radar of claim 1, wherein the actuator mechanically scans the UWB radar by rotating the UWB radar about an axis.

4. The UWB radar of claim 1, wherein the actuator mechanically scans the UWB radar by translating the UWB radar across a linear guide.

5. The UWB radar of claim 1, wherein the actuator mechanically scans the UWB radar by rotating an retractable shaft about a pivot, wherein the UWB radar is mounted at one end of the retractable shaft.

6. The UWB radar of claim 1, wherein the RF feed network is implemented using waveguides selected from the group consisting of microstrip waveguides, co-planar waveguides, and planar waveguides.

7. The UWB radar of claim 6, wherein the antennas are adjacent a first surface of the substrate and wherein the RF feed network is a co-planar waveguide network adjacent an opposing surface of the substrate, the plurality of distributed amplifiers being integrated into the opposing surface.

8. The UWB radar of claim 7, wherein the co-planar waveguide network is formed in metal layers adjacent the opposing surface of the substrate.

9. The UWB radar of claim 1, wherein each pulse-shaping circuit includes a driving amplifier operated in a saturation mode so as to rectify and level-shift the globally-synchronized RF signal and drive the resulting rectified and level-shifted RF signal across a plurality of delay lines, each pulse-shaping circuit including a combining amplifier to combine delayed signals from the delay lines into the RF pulses transmitted through the corresponding sub-array of antennas.

10. The UWB radar of claim 1, further comprising:

a receiving network adjacent the substrate, the receiving network configured to receive RF signals from the antennas and provide a combined received RF signal, and

a radar receiver operable to couple the combined received RF signal to a plurality of channels, wherein each channel includes a delay line operable to provide a delayed version of the combined RF signal, a multiplier operable to multiply the delayed version with a replica of the pulses provided by the pulse-shaping circuits to provide a multiplied signal, and an integrate and dump circuit operable to integrate the multiplied signal over multiple cycles of the transmitted pulses to provide an integrated signal; and

a combiner for combining the integrated signals into a combined integrated signal.

11. The UWB radar of claim 10, further comprising:

an analog-to-digital converter for digitally converting a version of the combined integrated signal into a digital signal responsive to cycles of an analog-to-digital converter (ADC) clock; and

a source for the ADC clock, the source including a coarse timer providing a coarse clock signal to a serially-connected plurality of delay circuits and a multiplexer for selecting from an output signal from each of the delay circuits to generate the ADC clock, whereby driving the multiplexer to select from the appropriate delay circuit on a pulse-by-pulse basis, successive pulses are sampled by the ADC at varying times within each successive sampled pulse.

12. A UWB radar, comprising:

a substrate;

a plurality of antennas adjacent the substrate, the plurality of antennas being arranged into a plurality of sub-arrays;

an oscillator for generating an RF signal

an RF feed network adjacent the substrate, the RF feed network including a feed port for receiving the RF signal from the oscillator, the RF feed network including a distributed plurality of amplifiers integrated with the substrate to amplify the RF signal from the oscillator as the RF signal propagates through the RF feed network;

a plurality of pulse-shaping circuits corresponding to the plurality of sub-arrays, each pulse-shaping circuit being configured to receive an amplified RF signal from the network and to process the amplified RF signal into pulses for transmission through the corresponding sub-array of antennas; and

an actuator for mechanically scanning the UWB radar so that the pulses transmitted by the antennas scan across a desired area.

13. The UWB radar of claim 12, wherein the substrate comprises a semiconductor wafer.

14. The UWB radar of claim 12, wherein the actuator mechanically scans the UWB radar by rotating the UWB radar about an axis.

15. The UWB radar of claim 12, wherein the actuator mechanically scans the UWB radar by translating the UWB radar across a linear guide.

16. A method, comprising:

driving a resonant network of distributed oscillators to produce an globally synchronized output signal having harmonics;

processing a selected one of the harmonics to produce a train of pulses;

transmitting selected ones of the pulses in the train of pulses according to a pulse repetition frequency (PRF);

receiving reflected pulses resulting form the transmission of the selected pulses; and

sampling the received reflected pulses wherein each pulse is arranged from a first portion to a last portion, and wherein each successive sample is delayed from the previous sample such that a sampled portion of a pulse for each sample successively cycles from the first portion to the last portion.

17. The method of claim 16, further comprising:

scanning the transmitted pulses across a desired area.

18. The method of claim 17, wherein the scanning comprises a mechanical scanning.

19. The method of claim 17, wherein the scanning comprising an electronic beam steering.