mission-systems

Sensor Systems

Signal Processing

The Signal Processing Group at Adaptive Methods provides real-time solutions for many of the complex SONAR challenges that exist in today's U.S. Navy. We are a leader in providing low-cost/high-performance products that use latest technologies and employ flexible and practical designs. Adaptive Methods has long supported the COTS insertion programs and open-architecture initiatives. We will continue to be an advocate for these programs, striving to keep the development and maintenance costs low for our customers while maintaining the highest level of performance.

Core Developments:

GMP – Generic Multi-Processor System

The GMP system is an engineering software platform used for development and testing of real-time signal processing applications. The software has evolved over many years, in support of numerous Navy SONAR programs. Originally designed as an advanced rapid-prototyping platform, the system now forms the core of most real-time signal processing systems produced by Adaptive Methods. The system is specifically designed for multi-dimensional array applications. Engineers at Adaptive Methods can easily transition new functionality into the GMP architecture, while relying on existing functions (FFTs, etc.) to complete the required signal processing flow. The processing functions are easily manipulated using the Graphical Signal Processing Toolkit. Upon successful integration into the GMP system, the desired functionality and supporting infrastructure is extracted from the baseline for use in the delivered product.

Graphical Signal Processing Toolkit

A core part of the GMP system is the signal processing graphical design toolkit. This toolkit includes a Java-based processing network editor that allows the designer to manage a visual representation of the processing functions to be applied to the various input signals available to our signal processing products. The editor performs automatic layout of the processing graph, and full validation of all user input. Processing graphs are saved in an XML format for other tools to use in generating processing instructions for signal processing applications.

As new processing functions are introduced into GMP, engineers can easily extend the editor by providing specification of the functions and their parameters in XML files, supplemented by a small amount of function-specific Java code.

GMLIPC – Generic Middleware Layer Inter-Process Communication

GMLIPC is Adaptive Methods’ communications infrastructure, providing a unified application programming interface to all of the data messaging transports used by our products. The publish/subscribe API supports a high- performance proprietary transport used within Adaptive Methods’ distributed processing subsystems as well as customer and integrator-specified external transports, such as CORBA.

Sensor Acquisition & Recording

Adaptive Methods’ Sensor Integration Group develops front-end interfaces to collect and format data from physical sensors and legacy data busses for the U.S. Navy. Both custom and commercial off-the-shelf (COTS) hardware are used to tap the data sources and bring the raw information into symmetric multi-processor (SMP) servers for formatting.

The Sensor Integration Group designs and builds interfaces to a variety of sources including analog sensors, parallel and serial digital data busses, legacy NTDS systems, ATM, FDDI, and Ethernet networks. For many applications, Adaptive Methods designs custom hardware and integrates it with available COTS hardware. In some cases, Adaptive Methods consults with manufacturers on design of new COTS hardware to meet specific requirements.

The Sensor Integration Group draws on many disciplines including digital and analog hardware design, software engineering, signal processing and analysis, operating systems, networking, and communications theory.

SOFTWARE

One core strength of the Sensor Integration Group is the common software product, Multi-Input Data Acquisition System (MIDAS), which can simultaneously communicate with each interface. The software leverages the symmetric multi-processor capabilities and is highly multithreaded -- thus capable of handling several I/O and processing tasks simultaneously. Multiple tasks can run independent of one another or coordinate for increased acquisition capacity or parallel processing. The software can be synchronized across multiple servers for additional capacity or remote acquisition capabilities. MIDAS is supported under both the Windows and Linux platforms.

The PC Test Set 2000 is an engineering software tool for the Windows platform designed to acquire and process multi-channel data and provide display and analysis tools. Designed for use in conjunction with acoustic sonar systems, the PC Test Set acquires raw data from a telemetry source and transforms it into the time, spectral, or spatial domains. The data is calibrated and displayed for the user who can use the built-in tools to analyze the data. In addition, the PC Test Set has automated tools to inform technicians of the health of the sonar system.

HARDWARE

Distributed, multi-channel synchronized Analog-to-Digital converter system.

This flexible system can theoretically sample analog data simultaneously from an unlimited number of channels. Multiple PCI-based ADC cards are spread across multiple servers. Adaptive Methods consulted with a COTS PCI manufacturer, General Standards, to develop one of the leading PCI-based 24-bit acquisition boards on the market. The system has been implemented to acquire data from a SQS-53C hull mounted sonar array for the U.S. Navy, as well as other smaller applications.

Distributed, multiple bus digital receiver

Adaptive Methods developed the capability to receive data from an arbitrarily large digital data bus and applied it to tap four 20-bit busses from a legacy Navy ASW sonar processor.

We designed and built a custom interface to synchronize four PCI-based digital acquisition cards to a common clock and frame format. Due to the distributed, multi-tasking design, the system is able to receive and process data at up to 96MB/sec.

Serial acquisition with arbitrary frame format

Adaptive Methods developed an interface to a PCI-based serial capture card to acquire data from a serial data stream. Frame synchronization is handled entirely in software eliminating the need for any custom hardware for specific applications. The system was deployed to receive towed-sonar array telemetry for the U.S. Navy.


Advanced Development

Adaptive Methods has performed advanced development work for the U.S. Navy and prime contractors since its incorporation in 1973. Our advanced development goals are to transition new signal and information processing technologies to fleet operational systems. Our products are comprised mainly of sonar signal processing algorithms such as conventional and adaptive beamformers for passive and active applications, detection and classification algorithms, tactical decision aids, sensor-array shape estimation algorithms, and multi-sensor data fusion algorithms. In addition, the Advanced Development Group provides systems engineering services, hydrodynamic modeling, tow body design and fabrication, and test & evaluation support to the U.S. Navy and prime contractors.

Signal Processing Developments

Adaptive Methods’ advanced development algorithms and technologies are integrated into broadly applicable software applications that support a variety of Navy programs. Many of these algorithms are developed in a peer-review environment, providing an opportunity for our developers to interact with leading experts in the field.

Adaptive Methods has developed & implemented a variety of conventional beamformer (CBF) algorithms with wide applications in uniformly spaced line arrays (ULAs) and many other array designs. These beamformers include real-time array shape estimation (ASE), array shape correction (ASC), and range focusing. We have developed and implemented a number of adaptive beamformer (ABF) algorithms for Navy technology demonstrations and fleet systems.