SBIR-STTR Award

Airborne SAR systems currently exist and are used for wide-area surveillance and ground mapping. The majority of deployed systems have frequencies (400 MHz-30 GHz) which, in most cases, cannot penetrate the soil to the depth required for detection of buried mines and unexploded ordnance. Lower frequencies are required for penetration of the ground. However, in the lower parts of the frequency spectrum, the techniques and waveforms currently used to achieve SAR across-track range resolution, such as pulse compression or impulse waveforms, create major sources of wide-band interference to other systems when the radar is transmitting. Conversely, all other emitters operating in these crowded frequency bands cause significant levels of interference to the SAR radar receiver. Amelex proposes to investigate new SAR system components and waveforms to generate an RF signal with sufficiently low frequwency to penetrate the ground and with the ability to achieve the across-track resolution required while reducing the EMI on both transmit and receive.

Airborne synthetic aperture radar (SAR) systems are required to provide all weather day/night imaging of ground targets. Requirements exist for a smaller, less expensive, and more covert SAR system. ZAI/Amelex has introduced a new SAR waveform and system which is very small, light weight, and low power. Recent experiments have demonstrated excellent resolution (~1.0 inch) while simultaneously reducing the energy required for SAR imagery by -30 dB for Low Probability of Intercept (LPI). This SBIR proposal has two primary Navy goals: 1) Validate the LPI SAR imaging waveform, and 2) Focus the development for transition to P-3 missions in a follow-on program. The Phase II prototype will be designed to demonstrate and validate SAR imagery with an initial design goal of 2-3 KM. The Phase II effort will then focus on the design of scalable modules for the power supply, power amplifier, and antenna array for an increased range capability of 20+ nm for possible implementation into a P-3C upgrade. A Transition Program would then take the approach identified as a starting point for final development, test, and evaluation of an extended range version of the LPI SAR, suitable for application to covert P-3 Intelligence, Surveillance, and Reconnaissance (ISR) missions requiring all-weather high resolution.

Benefit:
There are several anticipated benefits resulting from the proposed research. The new small airborne SAR system will be lighter, smaller, less expensive, and require less power than current systems. It will potentially provide for radar imagery which has increased resolution for target surveillance and identification. The proposed system also has the potential for the detection of buried landmines. There are immediate Govenmental and commercial markets for this technology.

Keywords:
Airborne, remote, mine, penetrating, ground, Imaging Radar, Light Weight Airborne Radar, synthetic aperture radar, Radar, sensing, Airborne Surveillance, detection, Ultra Wideband Radar