Systems

AN/AQS-24 Airborne Control & Data Processor

Colmek maintains annual contract engineering work for Northrop Grumman Underseas Systems and the U.S. Navy for a SONAR & Laser tow fish, primarily deployed from the MH-53E Sea Stallion helicopter. The AQS-24A and its predecessors, the AQS-24 and the AQS-14, have been the only operational airborne mine hunting search systems used by the U.S. Navy for the past 27 years. With a track record of proven reliability and performance across the globe, the system's high-resolution side-scan sonar and laser line scanner detects, localizes and classifies both bottom and moored mines in real-time at high area coverage rates.

Working as the key subcontractor since the inception of this system, a core function of the Colmek team has been the development and on-going technical upgrades to an airborne mounted electrical chassis, display and operator control console. This shock isolated helicopter mounted package houses the critical processing, control and data storage hardware and is directly exposed to the harsh operating environment of the MH-53; where dirt, hydraulic fluid, sea-spray and shock loading is constant. Colmek has also been solely responsible for the OS development and software used on this platform. The described system undergoes a rigorous test and performance evaluation, which is supported by Colmek both at their offices and in-field.

Relevant Items

• Shock and Vibration Tested MIL-STD-810F (Airborne Rotary Wing)
• OS - VxWorks and RT Linux (500,000 lines of C, C++)
• FPGA Integration (IP Core Development)
• Custom Telemetry Development
• Beam finder Interface, Controller & MAC
• Data Acquisition & Recording
• Managed Thermal Electric Cooling System
• Open GL texture rending in a real-time waterfall display
• Split color pallet for Sonar & Laser
• Interfaces: Radio, RGB, FSK, QAM, DVI, Ethernet, NAV, Joystick, Maintenance

Raytheon Over The Horizon Radar

Colmek developed the RF control unit and support equipment for Raytheon's Over The Horizon Radar (ROTHR), and maintains it for lifetime production. Several over the horizon radar systems were deployed starting in the 1950s and 60s as part of early warning radar systems, but were generally replaced by airborne early warning systems instead. As the need for accurate long-range tracking became less important with the ending of the Cold War, less-expensive ground based radar system such as ROTHR emerged as US Navy maritime reconnaissance and drug enforcement assets.

ROTHR detects targets at very long ranges, typically up to thousands of kilometers, and working as a key contractor Colmek developed the mission critical RF management components necessary to deliver the fidelity required to operate at the extreme ranges. Most critical parameters included noise suppression and accurate power ramping necessary to protect ultra high power antenna arrays. The critical RF section is implemented on field replaceable RF modules designed to fit in a high reliability 2U 19" rack mount chassis. The unit provides control for a remotely located operator to successfully apply RF power to the antenna farm, and provides the necessary fail safe mechanisms, all via a serial command/status interface and a discrete signal interface. The discrete interface is used to synchronize with a COTS system controller that manages all aspects of the system, and Colmek provides this interface in the form of a VME transition adapter that is installed in the rear of the backplane that supports the COTS system controller. Being a mission critical element Colmek was required to deliver product that met a full compliment of mil standards including quality control, environmental qualification, EMI certification, and reliability analysis.

Relevant Items

• RF Management Unit
• Safety RF Inhibits

• Custom Message Protocol
• Discrete Timing Synchronization
• Embedded Controller
• Custom 2U Mechanical Enclosure
• Custom Switching Power Supply
• Field Replaceable RF Modules
• Transition Adapter for COTS Integration
• Full Mil Requirements (EMI, Env)
• Rapid Prototype
• Mil Product Documentation

ORBCOMM

The ORBCOMM communication system consists of a constellation of 27 satellites placed in circular orbits approximately 800 kilometers above the earth. The system is designed to provide critical two-way communication and position determination services to mobile subscribers throughout the world. Subscriber terminals transmit to the satellite at 2400 bps on one of several available channels in the frequency range of 148 to 150.05 MHz. Typical subscriber message length is expected to be less than 30 characters, taking less than 100 milliseconds to transmit to the satellite. Subscriber terminals receive messages and other data from the satellites at 4800 bps in the frequency range of 137.0 to 138.0 MHz. The ground segment consists of a Satellite Control Center (SCC), a Network Control Center (NCC) and several regional Gateways situated at sites around the United States.

Colmek developed the Gateway Earth Station Modem to provides transmit and receive functions for this GES/satellite data link and communicates with the GES Computer over an Ethernet connection for data-in, data out, control and status messages. Colmek also provides various other test modem subscriber units for use within the ORBCOMM network. The GES Modem resides in a Dell server platform that in addition to providing the system level intelligence, manages TDMA traffic and provides the necessary network level data control and status over TCP/IP. The actual modem is implemented on a PCI Express card using software defined radio architecture and is supported by an accompanying RF card that resides in an adjacent PCIe slot.

Relevant Items

• Flexible Software Defined Radio Architecture
• Direct Sample RF
• Extensive DSP Functionality (FIR/CIC Filters)
• SO/QPSK Modulation
• 16 QAM Modulation Order (3/4 encode rate)
• 16 Channel TDMA
• BER 1e-5
• RF PCIe Form Factor
• DMA data transfer over PCIe
• GPS
• Linux OS
• Self Test
• 1U 19" Rack Mount