TECHNOLOGY AREA(S): Air Platform, Electronics

ACQUISITION PROGRAM: PMA-264 Air ASW Systems

The technology within this topic is restricted under the International Traffic in Arms Regulation (ITAR), 22 CFR Parts 120-130, which controls the export and import of defense-related material and services, including export of sensitive technical data, or the Export Administration Regulation (EAR), 15 CFR Parts 730-774, which controls dual use items. Offerors must disclose any proposed use of foreign nationals (FNs), their country(ies) of origin, the type of visa or work permit possessed, and the statement of work (SOW) tasks intended for accomplishment by the FN(s) in accordance with section 3.5 of the Announcement. Offerors are advised foreign nationals proposed to perform on this topic may be restricted due to the technical data under US Export Control Laws.

OBJECTIVE: Develop signal processing techniques to isolate and minimize in-band interferences that obscure or degrade the performance of a passive or active Anti-Submarine Warfare (ASW) system.

DESCRIPTION: Airborne ASW systems operate in selected portions of the electromagnetic spectrum. Passive and active acoustic sensors not only contend with friendly forces operating in-band but must contend with other non-cooperative signals that degrade sensor performance (i.e., environmental interference, unintended (out of band) transmissions from our own sensors, and commercial interference from other sources). The goal of this effort is to define, design and develop sensor-agnostic signal processing techniques to reduce or eliminate in-band interferences that obscure or degrade the performance of a passive or active ASW system (i.e., AN/SSQ-53, AN/SSQ-62, AN/SSQ-101, AN/SSQ-113, and AN/SSQ-125).

The proposed techniques would build upon the inherent nulling characteristics of a sensor while increasing degrees of freedom in the frequency, time, and spatial domains. The SBIR effort should explore techniques that could provide additional attenuation over the theoretical levels achieved through spatial nulling and that are robust enough to not be overly sensitive to manufacturing variability or degradation in array components due to aging or minor damage. Processing techniques considered for this investigation cannot assume any modifications to the existing system hardware; any proposed concepts must limit themselves to the data that is already provided by the passive or active airborne ASW system.

Work produced in Phase II may become classified. Note: The prospective contractor(s) must be U.S. Owned and Operated with no Foreign Influence as defined by DOD 5220.22-M, National Industrial Security Program Operating Manual, unless acceptable mitigating procedures can and have been implemented and approved by the Defense Security Service (DSS). The selected contractor and/or subcontractor must be able to acquire and maintain a secret level facility and Personnel Security Clearances, in order to perform on advanced phases of this contract as set forth by DSS and NAVAIR in order to gain access to classified information pertaining to the national defense of the United States and its allies; this will be an inherent requirement. The selected company will be required to safeguard classified material IAW DoD 5220.22-M during the advance phases of this contract.

PHASE I: Design and develop a solution(s) to characterize the severity of the in-band interference problem by identifying and quantifying U.S. and other navies� interferers, power levels, signals, and frequencies from active systems. Characterize the severity of habitual in-band non-cooperative signals that degrade sensor performance (e.g., directional noise, biologics, environment). Define signal processing techniques that could provide additional attenuation over the theoretical levels achieved through spatial nulling and that are robust enough to not be overly sensitive to manufacturing variability or degradation in array components due to aging or minor damage. Develop performance metrics in terms of overall system performance and quantify the effectiveness of each proposed processing concept. Produce plans for a prototype to be developed under Phase II.

PHASE II: Based on Phase I results, apply the top-ranked processing techniques to a passive and an active system of interest to the Air ASW community. Characterize each technique�s performance against actual data and investigate the practicality of inserting the processing into a P-8A and the MH-60R Acoustic Processor. Conduct a real-time demonstration of the performance of the selected processing techniques.

It is probable that the work under this effort will be classified under Phase II (see Description section for details).

PHASE III DUAL USE APPLICATIONS: Integrate the processing software into the operational P-8A and the MH-60R Acoustic Processor system. Support field test validation of the new functionalities. The SBIR-developed techniques to reduce the effects of acoustic noise have potential applications in many commercial environments. They could be applied to reduce the impact of acoustic noise in a variety of situations such as: ground crew personnel operating around commercial jetliners, people working in a manufacturing facility, or helmet-mounted microphones used by race car drivers. In all of these cases, acoustic noise picked up from the surrounding environment degrades the performance of microphone communication.

REFERENCES:

1. Urick, R. �Principles of Underwater Sound.� 3rd Edition. Los Altos Hills, CA: Peninsula Publishing, 1983. https://openlibrary.org/books/OL9317725M/Principles_of_Underwater_Sound

2. Cox, H. �Space-time processing for suppression of bottom reverberation.� Conference Record of the Twenty-Ninth Asilomar Conference on Signals, Systems and Computers, Oct 30-Nov 1, 1995, Vol.2, pp.1296-1299. DOI: 10.1109/ACSSC.1995.540908

3. Manolakis, D., Ingle, V. and Kogon, S. �Statistical and Adaptive Signal Processing.� Norwood, MA: Artech House, Inc., 2005. ISBN-10: 1580536107

4. Hodges, R. P. �Underwater Acoustics, Analysis, Design and Performance of Sonar.� John Wiley & Sons, Ltd, West Sussex, England, 2010. http://onlinelibrary.wiley.com/book/10.1002/9780470665244

KEYWORDS: Anti-Submarine Warfare (ASW); ASW Performance; Noise; Noise Cancellation; Signal; Signal Processing